The outlook for the U.S. economy and the federal budget depends on projected changes in the size and composition of the population. Each year, the Congressional Budget Office produces 30-year population projections that are based on existing laws and policies—in this case, as of September 30, 2025—and recent demographic trends. The projections provide a benchmark for assessing how potential legislation, administrative actions, and judicial decisions would affect the size and structure of the U.S. population. This report explains how CBO’s current population projections differ from the ones the agency released in January 2025 and then updated in September 2025 (to reflect laws and policies in place as of July 31, 2025).1

To project the U.S. population, CBO starts with recent data and then estimates future rates of fertility, mortality, and net immigration (the number of people who migrate to the United States minus the number who leave). In this report, the U.S. population is defined as the population used for estimating Social Security payroll taxes and benefits. (That measure, known as the Social Security area population, is described in Appendix C).

In CBO’s projections, the population increases from 349 million people in 2026 to 364 million in 2056. Population growth slows during that period—from an average rate of 0.3 percent a year over the next decade to 0.1 percent a year thereafter. Through 2029, the population grows because more people are projected to migrate to the United States than to leave it (positive net immigration) and because the annual number of births is projected to exceed the annual number of deaths. Starting in 2030, declining fertility rates are projected to cause births to fall short of deaths. Over time, the negative net contribution of births and deaths increasingly offsets the positive contribution of net immigration, until population growth slows to zero in 2056. The population is projected to shrink thereafter. (For details about how CBO’s projections differ from those of other government forecasters, see Appendix A.)

CBO’s population projections are highly uncertain, especially in the later years of the 2026–2056 period. If rates of fertility, mortality, or net immigration were higher or lower than CBO projects, the resulting population would differ in size and composition from the one described in this report. The effects of such differences would be larger in later years because the differences would compound over time.

The Size and Age Composition of the Population

CBO projects that the U.S. population will become older, on average, over the 2026–2056 period. The number of people age 65 or older is projected to rise through 2036, growing at an average annual rate of 1.6 percent. That rate is faster than the average growth rates projected for younger groups: −0.4 percent a year for people ages 55 to 64, 0.5 percent for people ages 25 to 54, and −0.8 percent for people age 24 or younger. After its initial rise, the growth of the population age 65 or older is projected to slow through 2056. The number of people ages 25 to 54 is projected to increase through 2042 and decrease thereafter. The population age 24 or younger is projected to decline in each of the next 30 years.

Components of Population Growth

Population growth is determined by births, deaths, and net immigration. In CBO’s projections, fertility rates continue to be lower than the replacement rate (the fertility rate required for a generation to exactly replace itself in the absence of immigration), which is 2.1 births per woman. Mortality rates continue to decline over the next 30 years, and immigration becomes an increasingly important source of population growth.

Fertility

CBO’s projection of fertility rates is based on its assessment of past trends. For the 20 years before the 2007–2009 recession, the total fertility rate averaged 2.02 births per woman. After peaking in 2007 at 2.12, that rate has generally fallen, mainly because of lower fertility rates for women under age 25. The total fertility rate was 1.64 births per woman in 2020 and declined to 1.60 in 2024 (the most recent year for which data on fertility were available when these projections were made). CBO projects that the total fertility rate will equal 1.58 births per woman in 2026, decline to 1.53 in 2036, and remain at roughly that rate for the following 20 years.

The fertility rate for women under 30 is projected to fall over the next three decades: from 0.74 births per woman this year to 0.60 in 2056. The rate for women age 30 or older, by contrast, is projected to increase—from 0.85 births per woman in 2026 to 0.93 in 2056—partly because CBO expects women to delay bearing children until older ages.

CBO’s projections of fertility rates are subject to considerable uncertainty. If future fertility rates differed from what CBO projects, the number of births and the age composition of mothers would look different from CBO’s projections.

Fertility, by Mother’s Place of Birth

CBO projects different fertility rates for women in the United States who were born in this country and those who were born elsewhere. The fertility rate for native-born women is projected to equal 1.53 births per woman in 2026, decline to 1.50 in 2032, and remain at that rate through 2056. The fertility rate for foreign-born women is projected to fall from 1.79 births per woman in 2026 to 1.66 in 2036 and then stay at that rate through 2056.

CBO projects separate fertility rates for foreign-born and native-born women using information on past fertility by age. That information comes mainly from the Centers for Disease Control and Prevention’s National Center for Health Statistics and the Census Bureau’s American Community Survey.2 After projecting age-specific rates, CBO sums them to create total fertility rates for native-born and foreign-born women. The total fertility rate for women as a whole is the average of the total rates for native-born and foreign-born women, weighted by the projected size of the populations of native- and foreign-born women of childbearing age (which CBO defines as ages 14 to 49).

Mortality

In CBO’s projections, mortality rates decline, causing average life expectancy at birth to increase from 79.0 years in 2026 to 82.3 years in 2056.

CBO projects mortality rates on the basis of historical trends, with adjustments to account for the effects of COVID-19. (Those projections reflect data from Social Security’s Board of Trustees through 2023.) Since at least the early 20th century, mortality rates in the United States have generally decreased (meaning that life expectancy has generally increased), and rates have fallen more quickly for younger adults than for older people. Since about 2010, however, the overall pace of decline has slowed, and mortality rates have risen for some groups—particularly young and middle-aged adults—because of such factors as drug overdoses, suicides, homicides, and transportation accidents.3

To account for those trends, CBO estimates that the mortality rate for each five-year age group will change at roughly the same average pace from 2024 to 2028 that it did from 2010 to 2019 (the last year before the COVID-19 pandemic). After 2028, mortality rates are projected to return to their more long-standing historical trends, declining at the average pace seen from 1950 to 2019. That time frame includes the period of faster decline before 2010 and the period of slower decline and reversal that some groups experienced from 2010 to 2019. The net effect is a continued decline in mortality rates beyond 2028.

Mortality rates are uncertain in the long term because factors such as advances in medical technology and changes in environmental conditions may have different effects in the future than they had in the past. Another area of uncertainty is whether the slowing of the decline in mortality rates for some groups from 2010 to 2019 will continue.

Net Immigration

To develop its overall projections of net immigration, CBO groups people into three categories (described in more detail in Appendix C):

• LPR+, which consists of lawful permanent residents (LPRs) and people who are eligible to apply to become LPRs on the basis of their current immigration status, such as asylees (people granted asylum) and refugees.
• INA nonimmigrants, which consist of people admitted as nonimmigrants under the Immigration and Nationality Act (INA), such as students and temporary workers.
• Other foreign nationals, which consist of people in the United States who are not in the first two categories and who have not subsequently become U.S. citizens or received LPR, asylee, or nonimmigrant status. That category includes people who entered the United States illegally and people who were allowed to enter through the use of parole authority and who may be awaiting proceedings in immigration court.

CBO’s projections of net immigration over the next two decades are based on its assessment of recent trends.4 After 2046, net immigration is projected to grow each year at roughly the same rate as total population growth in the previous year (0.02 percent, on average).

CBO develops its projections of net immigration so they fall in the middle of the likely range of outcomes in the absence of new legislation or administrative or judicial changes. Several factors cause those projections to be uncertain. For example, changing conditions in immigrants’ countries of origin could affect flows of immigration. Estimates of past immigration and projections of future immigration of people who enter the United States illegally are particularly uncertain because information about that group is hard to obtain. Estimates of how many people leave the country are also difficult to obtain. In addition, immigration could differ significantly from CBO’s projections because of future legislative or administrative actions or changes to enforcement policies, which are not reflected in the current projections.

Net Immigration, by Category

CBO projects that annual net immigration of lawful permanent residents and people eligible to apply for LPR status will grow slightly over the next 30 years (from 870,000 people in 2026 to 930,000 in 2056). On average, net immigration of people in that category averages 910,000 per year over the 2026–2056 period in CBO’s projections.

Net immigration of students, temporary workers, and other people in the INA non­immigrant category declined in 2025, CBO estimates, primarily because fewer students entered the United States. CBO projects that after 2025, the inflow of INA nonimmigrants will gradually return to the levels seen in the years shortly before the COVID-19 pandemic. The outflow of INA nonimmigrants will be reduced through 2029 by the smaller inflow of INA nonimmigrants in 2025, CBO projects. As a result of those factors, net immigration in the INA nonimmigrant category is projected to increase from 30,000 people in 2026 to 330,000 people in 2030. Such immigration is projected to fall after 2030 as INA non­immigrants who arrived in previous years begin to leave. In CBO’s projections, annual net immigration in the INA nonimmigrant category declines to 170,000 people in 2036 and remains near that number through 2056.

Net immigration of other foreign nationals was larger from 2021 to 2023 than it had been in recent decades, CBO estimates. Such immigration declined after a June 2024 executive order temporarily suspended most entries at the southern U.S. border, and it continued to decline in 2025 because of subsequent administrative actions. In 2025, net immigration of other foreign nationals turned negative, CBO estimates: 360,000 more people in that category left the country than arrived. CBO projects that net immigration of other foreign nationals will increase after 2025 as the number of immigrants joining that category each year returns to an amount consistent with its long-run historical average. Such immigration is projected to reach 140,000 people per year in 2036 and remain close to that number for the following two decades. (For more details, see Appendix B.)

Civilian Noninstitutionalized Population

As an input to its economic forecast, CBO projects two measures of the civilian noninstitutionalized population age 16 or older, which consists of people who are not on active duty with the armed forces, in penal or mental institutions, in detention facilities, or in homes for the elderly or infirm. Both projections are generally consistent with CBO’s projections of the growth of the Social Security area population.

• The first projection—which CBO calls Census Through 2020 Plus CBO Projection—incorporates population estimates made by the Census Bureau and researchers at the Federal Reserve Board through 2020. It reflects CBO’s estimates of population growth thereafter, including the agency’s estimates of net immigration after 2020. CBO uses that projection to estimate the size of the labor force and potential gross domestic product (the maximum sustainable output of the economy).
• The second projection—called BLS Through 2025 Plus CBO Projection—uses population data from the Bureau of Labor Statistics (BLS) through 2025 and then transitions to equal the Census Through 2020 Plus CBO Projection by 2031.5 CBO uses that projection to estimate the unemployment rate and payroll employment numbers that will be reported by BLS.

  Census Through 2020 Plus CBO Projection of the Civilian Noninstitutionalized Population, by Age Group

  Millions of people

  

  The number of people ages 25 to 54 in the civilian noninstitutionalized population—the group most likely to participate in the labor force—is projected to grow more slowly over the next 30 years than it did over the past 50 years.

  The number of people age 65 or older in that population—who are generally eligible for Social Security and Medicare and are less likely to be employed than younger people—is projected to average 75 million over the next 30 years, about twice the average size over the past 50 years.

Census Through 2020 Plus CBO Projection

For 1980 to 2020, the Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population is based on estimates produced by the Census Bureau and researchers at the Federal Reserve Board. Population estimates from the Census Bureau contain revisions that incorporate updated information about vital statistics and updated estimates of net immigration since the most recent decennial census. Such revisions are consistent within a decade but shift abruptly in the year of a decennial census. Researchers at the Federal Reserve Board have used that data to produce population estimates that are consistent across decades.6 Those estimates are the basis for CBO’s Census Through 2020 Plus CBO Projection.

After 2020, that projection of the civilian noninstitutionalized population grows at roughly the same rate as CBO’s projections of the total population. As a result, the Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population grows at an average rate of 0.3 percent a year over the next three decades, increasing from 277 million people in 2026 to 301 million people in 2056.7

BLS Through 2025 Plus CBO Projection

CBO’s BLS-based projection of the civilian noninstitutionalized population moves toward the Census Through 2020 Plus CBO Projection after 2025 and equals that projection (by age and sex) in 2031 and thereafter.8 In the BLS Through 2025 Plus CBO Projection, the civilian noninstitutionalized population increases from 276 million people in 2026 to 301 million in 2056—an average growth rate of 0.3 percent a year.

Changes to CBO’s Population Projections Since January 2025

CBO is now projecting a smaller population over the next three decades than it projected last January, when it published its previous annual report on the demographic outlook.9 (Those projections underpinned CBO’s most recent baseline budget projections, which were published in January 2025.)10

The Social Security area population is now projected to total 357 million people in 2035, which is 7 million (or 1.9 percent) fewer people than CBO projected in January 2025. The population is projected to grow to 364 million people in 2055 (the final year of the previous projections), which is 8 million (or 2.1 percent) fewer people than CBO projected last January. The majority of those changes occurred when CBO updated its January 2025 projections in September 2025; the September projections are compared with the current projections later in this report.

For the 2025–2035 period, changes since last January in projections of net immigration were the largest factor causing CBO to reduce its projection of the size of the population. Those changes were driven largely by administrative actions taken since January 20, 2025, and to a lesser extent by immigration enforcement provisions in the 2025 reconciliation act (Public Law 119-21).11 CBO now projects net immigration of 410,000 people (instead of 2.0 million) in 2025, 570,000 (instead of 1.6 million) in 2026, a total of 2.9 million (instead of 3.2 million) from 2028 to 2030, and 1.2 million (instead of 1.1 million) in 2035.

In the longer term, for the 2036–2055 period, lower projections of fertility rates were the largest factor contributing to CBO’s reduced projection of population size. CBO now projects that in 2055, the total fertility rate will equal 1.53 births per woman, down from 1.60 in the January 2025 projections. The number of births is now projected to average 3.3 million per year from 2036 to 2055, which is 200,000 (or 5.6 percent) fewer births per year than CBO projected last January.

Changes to Projected Fertility Rates Since January 2025

CBO is projecting lower fertility rates over the next three decades than it did last January. In the agency’s current projections, the total fertility rate was 1.59 births per woman in 2025, declines to 1.53 in 2035, and remains at about that level through 2055. In the January 2025 projections, by comparison, the total fertility rate was projected to be 1.62 births per woman in 2025, fall to 1.60 in 2034, and stay at that level through 2055.

Several factors have caused CBO to reduce its projections of fertility rates since January 2025:

• CBO adopted a new method for projecting separate age-specific fertility rates for native-born and foreign-born women, which resulted in lower projections of total fertility rates. (Previously, CBO used fertility projections from the United Nations to inform its projections of fertility rates for foreign-born women, which increased rates for women from certain countries. CBO no longer uses that method.)12
• Updated data from the Centers for Disease Control and Prevention (CDC) showed a lower total fertility rate in 2024 than CBO had estimated. Incorporating the new 2024 data reduced CBO’s projections of fertility rates in later years.
• Reductions since last January in CBO’s projections of net immigration also reduced projections of the total fertility rate because foreign-born women have higher fertility rates, on average, than women born in the United States.

  Total Fertility Rate in CBO’s January 2025 and January 2026 Projections

  Births per woman

  

  CBO’s projections of the total fertility rate have declined since last January because of a change in the method CBO uses to project fertility rates, new data for 2024, and changes in the projected composition of the childbearing population.

Changes to Projected Mortality Rates Since January 2025

CBO’s current projections of mortality rates are largely unchanged from the ones it published in January 2025. Because the size of the population is now projected to be smaller, however, there are fewer deaths in most years in CBO’s current projections than in the projections released last January.

Changes to Projected Net Immigration Since January 2025

Compared with its January 2025 projections, CBO’s current projection of total net immigration is smaller by 1.6 million people in 2025 and by 1.0 million people in 2026. Thereafter, the difference between the two projections narrows through 2029. Net immigration is now projected to be larger in 2030 and later years than CBO projected last January: by 70,000 people in 2035 and by 130,000 people in 2055.

Smaller projections of net immigration in 2025 and 2026 primarily reflect reductions in projections of net immigration by people in the other-foreign-national and INA non­immigrant categories, partly offset by increases in projections of net immigration by people in the LPR+ category. Reductions in projected net immigration by other foreign nationals and INA nonimmigrants mainly reflect the effects of administrative actions taken by the current Administration, although the effects of the 2025 reconciliation act also play a role.

By 2035, total projected net immigration is larger than in CBO’s January 2025 projections because of increases to projections of net immigration by people in the LPR+ and INA nonimmigrant categories. Those increases result from updated historical data for people in the LPR+ category and updated data and a new projection method for people in the INA nonimmigrant category.13 (Net immigration of people in the other-foreign-national category in 2035 is roughly the same as the long-run average for such immigration in CBO’s current and January 2025 projections.) In 2055, the current projection of total net immigration is larger by 130,000  people than last January’s projection because of greater projections of net immigration by people in the LPR+ and INA nonimmigrant categories.

Changes to CBO’s Population Projections Since September 2025

CBO published an update of its January 2025 demographic projections in September 2025 to reflect the effects of immigration-related changes made through July.14 Those updated projections reduced the estimated size of the population in 2055 by 5.4 million people (or 1.5 percent).

CBO now projects that the population will be smaller and will grow more slowly over the next 30 years than it projected in September (although the differences are smaller than the differences between the January 2025 and September 2025 projections). Changes to the projected size of the population in the near term result mainly from updated historical data from Social Security’s Board of Trustees about the size of the Social Security area population.15 The most recent historical data that CBO uses for that population is for 2021. New data suggest that the Social Security area population was smaller in 2021 than CBO had projected. That smaller estimated starting population—combined with slower population growth, mainly because of lower projected fertility rates—reduced the projected size of the population after 2021.

As a result of those changes, the population in 2025 is now estimated to be smaller by 1.8 million people (or 0.5 percent) than CBO projected in September. The population in 2055 is now projected to be smaller by 2.5 million people (or 0.7 percent) than in the September 2025 projections.

Changes to Projected Fertility Rates Since September 2025

CBO’s current projections of fertility rates for native-born and foreign-born women are based on past vital statistics data from the CDC’s National Center for Health Statistics and the Census Bureau’s American Community Survey.16

The total fertility rate is now projected to be 1.58 births per woman in 2026, decline to 1.53 in 2035, and remain at roughly that rate through 2055. In the September 2025 projections, by comparison, the total fertility rate declined to 1.58 in 2035 and to 1.57 in 2055. Those September projections were lower than the fertility rates CBO projected in January 2025. CBO has reduced them further in its current projections.

Because of the reduction in projected fertility rates, CBO is now projecting fewer births during the 2025–2055 period than it did in September. That change reduces the projected size of the population, particularly among younger age groups. For example, partly because of that change, the population age 24 or younger in 2055 is now projected to be smaller by 2.5 million people (or 2.8 percent) than CBO projected last September.

Changes to Projected Mortality Rates Since September 2025

CBO’s method for projecting mortality rates has not changed since last September. But the average number of deaths per year from 2026 to 2055 is now projected to be smaller by 10,000 (or 0.3 percent) than CBO projected in September, mainly because of a smaller projected population age 65 or older.

Projected life expectancies at birth and at age 65 are largely unchanged from CBO’s September projections. In both the current and the previous projections, life expectancy at birth averages 79.4 years from 2026 to 2035 and 81.7 years from 2046 to 2055. Life expectancy at age 65 averages 20.1 years from 2026 to 2035 and 21.5 years from 2046 to 2055.

Changes to Projected Net Immigration Since September 2025

CBO’s current estimates of total net immigration are smaller in 2021 and larger in 2022 than the amounts it estimated last September. Those differences result from changes to estimates of net immigration by people in the INA nonimmigrant category because CBO incorporated new population estimates by the Office of Homeland Security Statistics (OHSS) for 2019 to 2024.

In addition, net immigration was larger by 140,000 people in 2023, and smaller by 500,000 people in 2024, than CBO estimated in September. Those changes stem from revised estimates by various federal agencies of net immigration by people in the LPR+ and other-foreign-national categories. CBO estimates larger net immigration in the LPR+ category in 2023 on the basis of updated historical estimates. And CBO estimates smaller net immigration in the other-foreign-national category in 2024 mainly because of new information about the number of people who entered the United States without encountering a Customs and Border Protection official in that year.

CBO’s projections of total net immigration from 2025 to 2028 have not changed significantly since September 2025, but its projections of total net immigration from 2029 to 2055 are larger by an average of 70,000 people per year.

• Net immigration in the LPR+ category is now projected to be larger by 60,000 people per year, on average, over the 2025–2055 period than CBO projected last September, because of updated estimates of past net immigration in that category.
• Net immigration in the INA nonimmigrant category is projected to be larger by an average of 35,000 people per year over the 2025–2055 period. That increase stems from updates by OHSS to the historical data CBO used for projecting net immigration in the INA nonimmigrant category.
• Net immigration in the other-foreign-national category is projected to be smaller by 70,000 people per year, on average, from 2025 to 2036 than CBO projected in September. After 2036, net immigration of other foreign nationals is roughly unchanged from CBO’s September projections.

  Net Immigration in CBO’s September 2025 and January 2026 Projections

  Millions of people

  

  From 2025 to 2055, total net immigration is higher, on average, in CBO’s current projections than in its September 2025 projections because of higher projected net immigration of people in the LPR+ and INA nonimmigrant categories, partly offset by lower projected net immigration of people in the other-foreign-national category.

---

1. 1. For the previous projections, see Congressional Budget Office, The Demographic Outlook: 2025 to 2055 (January 2025), www.cbo.gov/publication/60875, and An Update to the Demographic Outlook, 2025 to 2055 (September 2025), www.cbo.gov/publication/61390.

2. 2. CBO uses historical estimates of age-specific fertility rates from the National Center for Health Statistics, which are provided by Social Security’s Board of Trustees. CBO estimates fertility by mother’s place of birth using data from the American Community Survey. See Social Security Administration, Office of the Chief Actuary, The 2025 Annual Report of the Board of Trustees of the Federal Old-Age and Survivors Insurance and Federal Disability Insurance Trust Funds (June 2025), www.ssa.gov/OACT/TR/2025; National Center for Health Statistics, “Birth Data Files, 2023” (public-use data file and documentation), https://tinyurl.com/3xez88wn; and Census Bureau, “2023 American Community Survey 1-Year Public Use Microdata Sample” (September 10, 2024), https://tinyurl.com/wpfpp943.

3. 3. Steven H. Woolf and Heidi Schoomaker, “Life Expectancy and Mortality Rates in the United States, 1959–2017,” Journal of the American Medical Association, vol. 322, no. 20 (November 26, 2019), pp. 1996–2016, https://doi.org/10.1001/jama.2019.16932.

4. 4. CBO’s projections of net immigration by people in the LPR+ category reflect data from the Social Security trustees through 2021. The projections of net immigration by people in the INA nonimmigrant category reflect data from the Office of Homeland Security Statistics through 2024. The projections of net immigration by other foreign nationals reflect data from several sources, which are described in Appendix B.

5. 5. When these projections were finalized, monthly population data were available from the Bureau of Labor Statistics through August 2025. CBO used those data to extrapolate the population for the remaining months of the calendar year.

6. 6. John Coglianese, Seth Murray, and Christopher J. Nekarda, Harmonized Population and Labor Force Statistics (Board of Governors of the Federal Reserve System, Finance and Economics Discussion Series 2025-057, August 2025), https://doi.org/10.17016/FEDS.2025.057.

7. 7. The projected growth of the Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population may differ from CBO’s projections of the growth of the Social Security area population for two reasons. First, CBO’s projections of the civilian noninstitutionalized population include only people age 16 or older, whereas the Social Security area population includes people of all ages. For example, the Social Security area population is projected to grow at an average rate of 0.1 percent per year from 2026 to 2056. But the segment of that population age 16 or older is projected to grow by an average of 0.3 percent per year over that period—the same rate as for the Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population. Second, the Social Security area population is measured as of January 1 each year, whereas the Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population is an annual average.

8. 8. The projected growth of the BLS Through 2025 Plus CBO Projection of the civilian noninstitutionalized population may differ from CBO’s projections of the growth of the Social Security area population for three reasons. First, the BLS Through 2025 Plus CBO Projection of the civilian noninstitutionalized population includes population control adjustments made by BLS each January to incorporate the latest population estimates produced by the Census Bureau, whereas the Social Security area population does not. Second, CBO’s projections of the civilian noninstitutionalized population include only people age 16 or older, whereas the Social Security area population includes people of all ages. Third, the Social Security area population is measured as of January 1 each year, whereas the BLS Through 2025 Plus CBO Projection of the civilian noninstitutionalized population is an annual average.

9. 9. Congressional Budget Office, The Demographic Outlook: 2025 to 2055 (January 2025), www.cbo.gov/publication/60875.

10. 10. Congressional Budget Office, The Budget and Economic Outlook: 2025 to 2035 (January 2025), www.cbo.gov/publication/60870.

11. 11. For information about how the 2025 reconciliation act is projected to affect the U.S. population, see Congressional Budget Office, An Update to the Demographic Outlook, 2025 to 2055 (September 2025), Box 1, www.cbo.gov/publication/61390.

12. 12. CBO’s new method is described above in the section titled “Fertility, by Mother’s Place of Birth.” CBO’s previous method for projecting fertility rates for foreign-born women is described in Congressional Budget Office, The Demographic Outlook: 2025 to 2055 (January 2025), p. 4, www.cbo.gov/publication/60875.

13. 13. CBO’s new method for projecting the number of INA nonimmigrants is described in Congressional Budget Office, An Update to the Demographic Outlook, 2025 to 2055 (September 2025), pp. 12–13, www.cbo.gov/publication/61390.

14. 14. Congressional Budget Office, An Update to the Demographic Outlook, 2025 to 2055 (September 2025), www.cbo.gov/publication/61390.

15. 15. CBO uses historical estimates of the Social Security area population from the Social Security Administration’s Office of the Chief Actuary. The office’s latest report is The 2025 Annual Report of the Board of Trustees of the Federal Old-Age and Survivors Insurance and Federal Disability Insurance Trust Funds (June 2025), www.ssa.gov/OACT/TR/2025. Updated data in that report are reflected in CBO’s current projections but not its September 2025 projections.

16. 16. CBO uses historical estimates of age-specific fertility rates from the National Center for Health Statistics, which are provided by Social Security’s Board of Trustees. CBO estimates fertility by mother’s place of birth using data from the American Community Survey. See Social Security Administration, Office of the Chief Actuary, The 2025 Annual Report of the Board of Trustees of the Federal Old-Age and Survivors Insurance and Federal Disability Insurance Trust Funds (June 2025), www.ssa.gov/OACT/TR/2025; National Center for Health Statistics, “Birth Data Files, 2023” (public-use data file and documentation), https://tinyurl.com/3xez88wn; and Census Bureau, “2023 American Community Survey 1-Year Public Use Microdata Sample” (September 10, 2024), https://tinyurl.com/wpfpp943.

Appendix A: Comparing CBO’s Population Projections With Those of Other Forecasters

This appendix compares the Congressional Budget Office’s latest population projections with those issued by Social Security’s Board of Trustees and by the Census Bureau. The Social Security trustees produce population projections each year that underlie their projections of the finances of the Social Security trust funds.1 Those population projections include what the trustees call an intermediate alternative, which represents their best estimates of future outcomes. The trustees also produce projections that reflect different assumptions about future rates of fertility, mortality, and net immigration. This comparison uses the trustees’ intermediate alternative, which was based on conditions as of December 2024.

The Census Bureau produces national population projections several times per decade. The most recent projections were published in 2023. They include a central projection of the U.S. population, known as the main series, as well as projections for scenarios in which net immigration in 2023 is about 50 percent greater or less than in the main series.2 In 2024, the Census Bureau released revised population estimates that included increases to its estimates of net immigration and the size of the population in 2022 and 2023.3 The Census Bureau has not yet produced new population projections based on the revised estimates, so this comparison looks at the bureau’s 2023 projections.

The Census Bureau uses a smaller measure of population than CBO and the Social Security trustees do. The Census Bureau’s projections are for the resident population of the United States, which consists of people residing in the 50 states and the District of Columbia (the population counted in the census conducted every 10 years). CBO’s and the Social Security trustees’ projections are for the Social Security area population, which is used for estimating Social Security payroll taxes and benefits. That population consists of the resident population plus U.S. citizens and others living abroad who are eligible for Social Security benefits.

CBO’s current projections of the size of the population exceed the Census Bureau’s 2023 main series and low-immigration projections throughout the 2026–2056 period (see Figure A-1). They are also larger than the Census Bureau’s high-immigration projections through 2032. CBO’s estimate of population size is slightly larger than the trustees’ intermediate estimate for 2025, but after that, the trustees’ projections exceed CBO’s through 2056.

Fertility Rates

CBO’s projection of the total fertility rate is similar to the Census Bureau’s and lower than the Social Security trustees’ (see Figure A-2). CBO projects that the total fertility rate will decline from 1.58 births per woman in 2026 to 1.53 in 2036 and remain at roughly that rate through 2056. The Census Bureau projects that the total fertility rate will gradually decrease from 1.63 births per woman in 2026 to 1.62 in 2036 and 1.60 in 2056. In contrast, the Social Security trustees project that the total fertility rate will rise from 1.65 births per woman in 2026 to 1.90 in 2045 and remain at that rate through 2056.

CBO’s and the Census Bureau’s projections of fertility rates by age group differ more than their projections of the total fertility rate. Both agencies project that the fertility rate for women under age 30 will decline over the next 30 years. But CBO projects a larger decrease (from 0.74 births per woman in 2026 to 0.60 in 2056) than the Census Bureau does (from 0.83 to 0.78 over that period). Both CBO and the Census Bureau project that the fertility rate for women age 30 or older will rise over the next three decades. But CBO projects a bigger increase (from 0.85 births per woman in 2026 to 0.93 in 2056) than the Census Bureau does (from 0.80 in 2026 to 0.82 in 2056).

The Social Security trustees’ projection of the total fertility rate is higher than CBO’s because of differences in projected trends in childbearing by age. The trustees expect the fertility rate for women under 30 to decline more slowly than CBO projects: from 0.80 births in 2026 to 0.78 in 2056. Both CBO and the trustees project that the fertility rate for women 30 or older will rise—reflecting delayed childbearing by women who had fewer or no children when they were under 30—but CBO projects a smaller increase for that age group than the trustees do.

Mortality Rates

On the basis of past trends (with adjustments for the estimated effects of COVID-19 through 2025), CBO projects that mortality rates will decline over the next 30 years, increasing the average life expectancy at birth from 79.0 years in 2026 to 82.3 years in 2056 (see Figure A-3). By comparison, the Social Security trustees project a slightly higher average life expectancy at birth in 2026 (79.3 years) and a slightly lower average in 2056 (82.1 years). Both CBO’s and the trustees’ projections of life expectancy are lower than those of the Census Bureau, which projects an average life expectancy at birth of 80.2 years in 2026 and 83.8 years in 2056.

Net Immigration

CBO’s projections of net immigration are based on information from the Department of Homeland Security. According to data from the department, the number of immigrants entering the United States who were not lawful permanent residents, people granted refugee or asylum status, foreign students, or temporary workers—a category called other foreign nationals—increased significantly from 2021 to 2024 and then contracted in 2025. (For more about the other-foreign-national category of immigration, see Appendix B.)

CBO’s estimates of total net immigration are larger than the Social Security trustees’ for 2022 and 2023: by 865,000 people and 687,000 people, respectively (see Figure A-4). For years after 2023, CBO’s estimates of net immigration are smaller than the trustees’: by 460,000 people for 2024, 1.7 million people for 2025, and an average of about 333,000 people per year for 2026 to 2036. CBO’s estimates are closer to the trustees’ after 2036, when CBO projects that net immigration will return to its past long-run average.

Compared with the Census Bureau’s main series, CBO’s estimates of net immigration are larger for 2023 and 2024. The bureau’s main series was published in 2023 and does not incorporate the increase in immigration that CBO estimated beginning in 2021. CBO’s projections are smaller than the Census Bureau’s main series for 2025 to 2028 and larger than the main series for the remainder of the projection period. CBO’s estimates also exceed the projections for the Census Bureau’s high-immigration scenario for 2023 and 2024: by 1.9 million people and 674,000 people, respectively. Thereafter, CBO’s projections are lower than the Census Bureau’s high-immigration projections. (CBO’s projections of net immigration exceed the Census Bureau’s low-immigration projections in all years of the projection period.)

In 2024, the Census Bureau released new estimates of net immigration over the 2022–2024 period that are closer to CBO’s current estimates of immigration in those years.4 The Census Bureau now estimates that, on net, 2.8 million people immigrated to the United States from July 2023 to July 2024. CBO estimates that, on net, 3.5 million people immigrated to the United States in calendar year 2023 and 2.3 million people did so in calendar year 2024. The Census Bureau also estimates that net immigration totaled 4.4 million people from April 2020 to July 2023, whereas CBO estimates that net immigration totaled 8.6 million people from the beginning of 2020 to the end of 2023. The Census Bureau has not released new population projections that incorporate its updated immigration estimates from 2024.

---

1. 1. For more information about those projections, see Social Security Administration, Office of the Chief Actuary, The 2025 Annual Report of the Board of Trustees of the Federal Old-Age and Survivors Insurance and Federal Disability Insurance Trust Funds (June 2025), www.ssa.gov/OACT/TR/2025.

2. 2. For more information about those projections, see Census Bureau, Methodology, Assumptions, and Inputs for the 2023 National Population Projections (November 2023), https://tinyurl.com/5n7wemnz.

3. 3. For more information about those estimates, see Census Bureau, Methodology for the United States Population Estimates: Vintage 2024: Nation, States, Counties, and Puerto Rico—April 1, 2020, to July 1, 2024 (December 2024), https://tinyurl.com/5erua2ty.

4. 4. Mark Gross and others, “Census Bureau Improves Methodology to Better Estimate Increase in Net International Migration,” Random Samplings (Census Bureau blog entry, December 19, 2024), https://tinyurl.com/3345pjs6.

Appendix B: Net Immigration of People in the Other-Foreign-National Category

As part of producing its current population projections, the Congressional Budget Office revised its projections of how many people in the other-foreign-national (OFN) category will enter or leave the United States. Those projections reflect laws and policies that were in place as of September 30, 2025.

The OFN category includes three main groups of people:

• Those who entered the United States illegally and who have not obtained a permanent legal status,
• Those who previously resided in the United States legally in a temporary status but who remained in the country after that legal status expired, and
• Those who were permitted to enter the country lawfully through the use of parole authority and who may be awaiting proceedings in immigration court.1

In this report, net immigration of other foreign nationals in a given year equals the number of people who join the OFN category when they arrive from a foreign country, plus the number of people already in the United States who move into that category when their temporary legal status expires, minus the number of people who leave the OFN category by emigrating or by obtaining a legal immigration status.

CBO now estimates that 360,000 more people left the OFN category in 2025 than joined it, meaning that net immigration of other foreign nationals equaled −360,000 people in that year. That estimate is smaller than the projections for 2025 that CBO published in January and September 2025: 1.1 million people and −290,000 people, respectively.2 The current estimate for 2025 is also smaller than the amount of net immigration in the OFN category seen in recent years. Such net immigration averaged 1.6 million people per year from 2021 to 2024, CBO estimates.

CBO projects that net immigration of other foreign nationals will generally increase in the next several years, as the number of immigrants joining that category returns to an amount consistent with its long-run historical average. In CBO’s projections, annual net immigration in the OFN category equals −330,000 people in 2026 and 2027 and then gradually rises to −130,000 people in 2030 and 140,000 people in 2036. After that, net immigration of other foreign nationals remains around 140,000 people per year through 2046 and then grows each year at roughly the same rate at which the overall population grew in the previous year.

Projections of net immigration of other foreign nationals are uncertain for many reasons. For example, such immigration could differ significantly from CBO’s projections because of future legislative or administrative actions or changes to enforcement policies. (Future actions are not incorporated in the current projections, which are based on existing laws and regulations.) In addition, there is significant uncertainty about how many people in the OFN category will be removed from the interior of the United States (as opposed to being removed at the border). Changing conditions in immigrants’ countries of origin could also affect amounts of immigration and emigration. And information about other foreign nationals is hard to obtain. CBO will continue to evaluate new information as it becomes available.

CBO’s Estimates for 2025

The estimate that net immigration of other foreign nationals equaled −360,000 people in 2025 was a significant reduction from the amount of such immigration that occurred in recent years. CBO estimates that net immigration in the OFN category averaged −130,000 people from 2010 to 2019 and then totaled 830,000 people in 2021, 2.0 million people in 2022, 2.4 million people in 2023, and 1.3 million people in 2024.

CBO’s estimates of net immigration of other foreign nationals are based on publicly available data and information from the Department of Homeland Security (DHS). Beginning in January 2025, most people attempting to enter the United States were required to wait outside the country until their hearing in immigration court, and some humanitarian parole programs were canceled. As a result, data from DHS show that in early 2025, officials with Customs and Border Protection (CBP) encountered fewer people attempting to enter the United States per month than they did in each of the previous four years. (CBP officials include personnel in the Office of Field Operations who work at official ports of entry and Border Patrol officers who work between ports of entry.)

To calculate net immigration of other foreign nationals in 2025, CBO first projected the total number of such immigrants who were expected to enter the United States or overstay their temporary status in that year. CBO then subtracted the number of other foreign nationals projected to emigrate, obtain a permanent legal immigration status, or be removed in 2025.

Estimates of People Joining the Other-Foreign-National Category in 2025

A total of 380,000 people joined the OFN category last year, CBO estimates (see Figure B-1). That total is the sum of CBO’s estimates for four groups: people who entered the United States between official ports of entry and were released into the country by CBP officials (20,000), people who entered at ports of entry and were released into the country by CBP officials (60,000), people who entered without encountering a CBP official (50,000), and people who entered legally in a temporary status but overstayed their term of residency (260,000).

Two executive actions in late January 2025 reduced the number of immigrants joining the other-foreign-national category:

• Executive Order 14165 reinstated the policy of Migrant Protection Protocols, which require people who want to apply for asylum in the United States to return to the territory from which they came.3 That order also ended all categorical parole programs and ceased the use of the CBP One app as a method of paroling or facilitating the entry of people into the United States.
• Proclamation 10888 suspended all entries at the southern U.S. border, including by people seeking asylum.4

Before those executive actions were taken, people who arrived between official ports of entry were generally released into the United States with humanitarian parole, a notice to appear in immigration court, or both while they awaited their immigration proceedings. People could also use the CBP One app to schedule an appointment at a port of entry and could later be released into the United States with humanitarian parole, a notice to appear in immigration court, or both.

People Arriving Between Official Ports of Entry. In 2025, about 20,000 immigrants were released into the United States after encountering a CBP official somewhere other than at an official port of entry, CBO estimates. Nearly all of those people were encountered by the Border Patrol at the southern border. Some were released with a notice to appear in immigration court or with parole; others were detained with an arrest warrant. Immigrants who were detained included unaccompanied children, who were temporarily placed in the custody of the Office of Refugee Resettlement, as well as people who were given a notice to appear and transferred to the custody of Immigration and Customs Enforcement, from which they were later released, in many cases.5

CBO’s estimate of 20,000 people released between official ports of entry in 2025 marks a significant reduction from the 540,000 people estimated to have done so in 2024. The number of people released into the United States after encountering a CBP official between ports of entry averaged 80,000 per month from January to May 2024. After an executive order in June 2024 temporarily suspended the entry of most noncitizens at the southern border, that average slowed to 20,000 people per month from June to December 2024. Releases continued to decline in 2025 because of the reinstatement of Migrant Protection Protocols under Executive Order 14165 and the suspension of entries at the southern border under Proclamation 10888. Such releases numbered roughly 7,000 people in January 2025 and then declined to an average of about 1,000 people per month from March to August, CBO estimates.6 CBO projected that releases would continue to average 1,000 per month for the rest of 2025.

People Arriving at Official Ports of Entry. In 2025, the Office of Field Operations released about 60,000 immigrants into the United States who arrived at official ports of entry, CBO estimates. The office released a total of 50,000 people from January to August: 30,000 with a notice to appear in immigration court and 20,000 with parole.7 Most of those releases (about 30,000) occurred in January. After that, such releases fell significantly: to 4,000 people in February and to an average of 2,000 people per month from March to August, CBO estimates. CBO projected that such releases would continue to average 2,000 per month for the rest of 2025.

In 2024, CBO estimates, 960,000 people were released into the country at official ports of entry. In CBO’s estimation, the sharp drop in 2025 occurred mainly because Executive Order 14165 ended the use of the CBP One app to schedule appointments with CBP officials and ended the Processes for Cubans, Haitians, Nicaraguans, and Venezuelans (CHNV) parole program. In fiscal year 2024, about 45,000 appointments per month were scheduled using the CBP One app, and many of those appointments resulted in the release of people into the country with humanitarian parole, a notice to appear in immigration court, or both. An additional 24,000 people per month entered the United States under the CHNV parole program in fiscal year 2024. The suspension of all entries at the southern border under Proclamation 10888 also reduced the number of people who entered at official ports of entry in 2025, CBO estimates.

People Not Encountering a CBP Official. About 50,000 immigrants in the other-foreign-national category crossed a U.S. border in 2025 without encountering an official from Customs and Border Protection, CBO estimates. That total comprises two groups of immigrants:

• People who were directly or indirectly observed making an unlawful entry, who were not turned back or apprehended, and who are no longer being pursued by the Border Patrol;8 and
• People who crossed a U.S. border without being seen or detected (such as by cameras or sensors).

To estimate the number of people in the first group, CBO uses information released by DHS. Official estimates for 2023 and 2024 were not available at the end of September 2025, when CBO completed these projections. But Border Patrol officials indicated in media reports that 670,674 people were observed entering the country in fiscal year 2023 who were not caught or pursued.9 In addition, DHS has reported that the number of people who entered the United States without encountering a CBP official was about 60 percent lower in fiscal year 2024 than in fiscal year 2023.10 On the basis of that information, CBO estimated that such immigrants numbered 270,000 in fiscal year 2024.

To estimate how many people entered the country in 2025 without encountering a CBP official, CBO used information from DHS about different parts of the year to estimate an annual total. First, CBO estimated that such immigration in January 2025 was consistent with the monthly average seen in 2024 (about 22,000 people). Then, CBO used information from DHS that 11,867 people, or 83.6 per day, entered the United States without encountering a CBP official from February 1 to June 22.11 Extending that daily average through the end of June led CBO to estimate that a total of about 13,000 such immigrants entered the country from February to June. Lastly, to estimate the number of people who entered during the rest of the year, CBO projected that the amount of such immigration experienced in June (1,300 per month) would continue from July to December. In total, those figures result in an estimate of 43,000 people directly or indirectly observed entering the country without encountering a CBP official in 2025.

The Chief of the Border Patrol testified before Congress that the number of people directly or indirectly observed entering without encountering a CBP official probably undercounts the total number of immigrants who do not encounter a CBP official by 10 percent to 20 percent.12 To account for people who crossed the border without being seen or detected by CBP officials—the second group—CBO adjusted its estimate of 43,000 people upward by 15 percent, to 50,000 people in 2025.

That estimate is much smaller than the roughly 800,000 and 300,000 people estimated to have entered the United States without encountering a CBP official in 2023 and 2024, respectively. In CBO’s assessment, several factors, including increased immigration enforcement, have reduced the number of people attempting to cross or successfully crossing the U.S. border without encountering a CBP official. Information about the number of people who enter the country without encountering a CBP official is scarce. CBO’s estimate of that number for 2025 is subject to significant uncertainty.

People Overstaying Their Temporary Status. CBO estimates that 260,000 people who previously resided in the United States legally in a temporary status remained in the country in 2025 after their legal status expired in 2024. That estimate is based on data from DHS, which indicated that 482,954 people may have overstayed their temporary status in fiscal year 2024.13 CBO reduced that figure because of its assessment, based on information from earlier years, that a sizable fraction of people who overstayed their temporary status did so for only a short time. DHS reported that 46 percent of people who were estimated to have overstayed their visa at the end of fiscal year 2016 and who remained in the country were no longer in that category by May 2018 because they had either left the United States or obtained a permanent legal status in the intervening period.14 In other words, DHS estimated that only 54 percent of people who had overstayed their visa at the end of 2016 were still overstaying their visa 20 months later. Similar declines were seen in the number of people who may have initially overstayed in 2015 or during the 2017–2020 period and who remained in later periods.

On the basis of that information, CBO estimates that about 260,000 people who had entered legally in previous years but overstayed their temporary status were present in the United States in 2024. In CBO’s estimation, the same number of people overstayed in 2025.

Estimates of People Leaving the Other-Foreign-National Category in 2025

In CBO’s assessment, a total of about 750,000 people in the OFN category voluntarily emigrated from the United States, obtained a permanent legal status, or were removed from somewhere inside the country in 2025. That total is smaller than the number of people estimated to have left the OFN category in 2024 (see Figure B-2).

People Emigrating Voluntarily. CBO estimates that about 400,000 people in the other-foreign-national category left the United States voluntarily in 2025. That estimate reflects projected changes in how people respond to increased immigration enforcement. After 2025, CBO’s estimates of voluntary emigration also reflect the end of Temporary Protected Status (TPS) for some immigrants who had it.15

CBO’s projections of emigration rates for other foreign nationals in 2025 vary depending on how long the immigrants have lived in the United States. Six percent of other foreign nationals are projected to emigrate voluntarily within the first year of their arrival, an additional 3 percent within two years, and another 3 percent within three years. An additional 2 percent are projected to emigrate in the fourth year after their arrival and in each year thereafter. Those percentages are three-quarters the size of the emigration rates that CBO projected in January 2025. In the agency’s assessment, increased immigration enforcement makes it less likely that other foreign nationals will leave the United States voluntarily, because that enforcement would make it more difficult for them to reenter the country later.16

CBO also estimates that some people whose Temporary Protected Status has been terminated will voluntarily leave the country. Because several TPS designations were terminated in the middle of 2025 and have been subject to legal challenges, CBO does not estimate that any people whose TPS was terminated voluntarily emigrated in 2025. However, CBO estimates that about 10,000 people per year will do so in 2026 and 2027. 

CBO developed those estimates by first estimating the number of people whose TPS has been terminated and who do not have another legal status (such as a pending application for asylum) to protect them from removal. In CBO’s estimation, about 50 percent of people who previously held TPS would not have another legal status to protect them from removal if they lost TPS. CBO then multiplied the number of people in that group by emigration rates that vary according to how long ago people’s TPS was terminated and how recently they arrived. For people who came to the United States within the past 10 years, CBO estimated that 8 percent will voluntarily emigrate in the year their TPS is canceled and an additional 4 percent a year will emigrate in the first and second years after termination. For people who arrived more than 10 years ago, estimated emigration rates are half of those percentages.

People Removed From Inside the Country. CBO estimates that 120,000 people from the other-foreign-national category were removed from the interior of the United States in 2025. That estimate does not reflect the policy changes enacted in the 2025 reconciliation act (Public Law 119-21), which CBO estimates will affect interior removals beginning in 2026.17

CBO estimated the number of interior removals in 2025 using data provided by Immigration and Customs Enforcement (in response to a Freedom of Information Act request) to the Deportation Data Project about the number of monthly removals through July 28, 2025.18 On the basis of those data, CBO estimates that 70,000 people were removed from inside the United States through July 2025, or about 300 people per day. CBO projected that interior removals would continue to average 300 per day for the rest of 2025.

People Obtaining a Permanent Legal Status. CBO estimates that 225,000 other foreign nationals obtained some type of permanent legal status in 2025. That group includes people who are (or will become) immediate relatives of U.S. citizens, people who are not immediate relatives of U.S. citizens but who are eligible for a permanent legal status under a family preference, people who are granted asylum, and people who qualify under the Cuban Adjustment Act, as amended.19

CBO’s Projections for 2026 to 2056

In CBO’s projections, net immigration of people in the other-foreign-national category increases from −360,000 people in 2025 to −330,000 people in both 2026 and 2027. After that, such net immigration gradually increases until it reaches 140,000 people in 2036. OFN net immigration is projected to remain at 140,000 people per year through 2046 and then grow each year at roughly the same rate at which the overall population grew in the previous year. That growth rate is slower than CBO projected in its January 2025 and September 2025 demographic projections. As a result, CBO is now projecting less net immigration of people in the OFN category in the last decade of the projection period than it did in January or September 2025.

---

1. 1. Parole authority allows people to enter the United States temporarily on a case-by-case basis for urgent humanitarian reasons or for significant public benefit.

2. 2. Congressional Budget Office, The Demographic Outlook: 2025 to 2055 (January 2025), www.cbo.gov/publication/60875, and An Update to the Demographic Outlook, 2025 to 2055 (September 2025), www.cbo.gov/publication/61390.

3. 3. Executive Order 14165, “Securing Our Borders,” Presidential Document, 90 Fed. Reg. 8467 (January 30, 2025), https://tinyurl.com/46mwu4af.

4. 4. Proclamation 10888, “Guaranteeing the States Protection Against Invasion,” Presidential Document, 90 Fed. Reg. 8333 (January 29, 2025), https://tinyurl.com/3ah5zpwy.

5. 5. Customs and Border Protection, “U.S. Border Patrol—Dispositions and Transfers: USBP Monthly Southwest Border Encounters by Processing Disposition” (September 30, 2025), https://tinyurl.com/42rksdwh.

6. 6. Ibid.

7. 7. The estimates in this report of the number of people released by the Office of Field Operations with a notice to appear or with parole reflect the office’s disposition categories “Paroled” and “Notice to Appear.” For an explanation of those categories, see Transactional Records Access Clearinghouse, “About the Data: Stopping ‘Inadmissibles’ at U.S. Ports of Entry” (September 5, 2024), https://tinyurl.com/465rp5a5. The office released some people with both a notice to appear and parole.

8. 8. That group is sometimes referred to as “got aways,” as described in 6 U.S.C. § 223(a)(3), http://tinyurl.com/5n7uv2um.

9. 9. Adam Shaw and Bill Melugin, “New Data Reveals Illegal Immigrants Eluding Border Patrol Spiked Under Biden, Surpassing Predecessors,” Fox News (May 15, 2024), https://tinyurl.com/5n964et2.

10. 10. Department of Homeland Security, “U.S. Department of Homeland Security Has Taken Unprecedented Steps Resulting in a Border More Secure Than It Was Four Years Ago” (fact sheet, January 17, 2025), https://tinyurl.com/955zjhhy.

11. 11. Department of Homeland Security, “Since DHS Immigration Enforcement in Los Angeles Began, Border Crossings Continue to Plummet” (press release, June 24, 2025), https://tinyurl.com/4jtzu6jd.

12. 12. Testimony of Raul L. Ortiz, Chief, Border Patrol, before the House Committee on Homeland Security (March 15, 2023), time stamp 1:08:15, http://tinyurl.com/3tbv2w65.

13. 13. Those people are known in the data as “suspected in-country overstays.” See Customs and Border Protection, Entry/Exit Overstay Report: Fiscal Year 2024 Report to Congress (July 16, 2025), Table 1, pp. 11–12, https://tinyurl.com/yc579p9n.

14. 14. Department of Homeland Security, Fiscal Year 2017 Entry/Exit Overstay Report (October 2018), Table 9, p. 31, https://tinyurl.com/ymd2hz9r.

15. 15. In 2025, TPS designations were terminated for people from eight countries: Afghanistan, Cameroon, Haiti, Honduras, Nepal, Nicaragua, Syria, and Venezuela (2023 designation). Some of those terminations have been challenged in court and are pending litigation. CBO included all designations that have been terminated in its projections of voluntary emigration after 2025.

16. 16. Douglas S. Massey, Jorge Durand, and Karen A. Pren, “Border Enforcement and Return Migration by Documented and Undocumented Mexicans,” Journal of Ethnic and Migration Studies, vol. 41, no. 7 (2015), pp. 1015–1040, https://doi.org/10.1080/1369183X.2014.986079; and Rene R. Rocha and others, “Policy Climates, Enforcement Rates, and Migrant Behavior: Is Self‐Deportation a Viable Immigration Policy?” Policy Studies Journal, vol. 42, no. 1 (February 2014), pp. 79–100, https://doi.org/10.1111/psj.12043.

17. 17. Congressional Budget Office, An Update to the Demographic Outlook, 2025 to 2055 (September 2025), Box 1, www.cbo.gov/publication/61390.

18. 18. For more information, see Deportation Data Project, “Immigration and Customs Enforcement” (accessed September 30, 2025), https://deportationdata.org/data/ice.html.

19. 19. Cuban Adjustment Act, P.L. 89-732, 80 Stat. 1161 (1966) (codified as amended at 8 U.S.C. § 1255 note), https://tinyurl.com/yzvsv7dy.

Appendix C: Terms Used in This Report

In this report, population refers to the Social Security area population, which includes all residents of the 50 U.S. states and the District of Columbia, as well as civilian residents of U.S. territories. It also includes federal civilian employees and members of the U.S. armed forces living abroad and their dependents, U.S. citizens living abroad, and noncitizens living abroad who are eligible for Social Security benefits on the basis of their earnings while in the United States.

The Congressional Budget Office projects the Social Security area population on January 1 of a given year by starting with the population on January 1 of the previous year, adding the projected number of people who are born into that population or who immigrate (and thus become part of that population), and subtracting the projected number of people who die or who emigrate (and thus are no longer part of that population) during that year.

CBO divides the Social Security area population into four main categories. The first category, U.S. nationals, consists mainly of U.S citizens. It also includes people who were born or whose parents were born in American Samoa or on Swains Island on or after the date the United States acquired those possessions; such people are U.S. nationals but not U.S. citizens by birth.

The second category, called LPR+, consists of lawful permanent residents (LPRs) plus people who are eligible to apply to become LPRs on the basis of their current immigration status:

• LPRs include people who were granted that status while in the United States, as well as people who gained admission from abroad. People can become eligible for LPR status in various ways: by becoming an immediate relative of a U.S. citizen, by receiving an immigrant visa through one of the family-based or employment-based preference categories, by receiving a diversity visa (which applies to countries with low rates of immigration to the United States), or by meeting other requirements.
• People who are eligible or will soon become eligible to apply for LPR status include certain immediate relatives of U.S. citizens (such as fiancés or fiancées) and people granted refugee status, asylum, or another status (in the case, for example, of victims of human trafficking and certain parolees) that may allow them to adjust their status to that of a lawful permanent resident.1

The third category, INA nonimmigrants, comprises temporary workers, student exchange visitors, qualifying family members, officials of foreign governments, and other people admitted as nonimmigrants under the Immigration and Nationality Act (INA), while they remain in that status.2

The final category, other foreign nationals, consists of people in the United States who are not part of the U.S. national, LPR+, or INA nonimmigrant categories. Other foreign nationals include people in the following groups who did not later become U.S. citizens or receive LPR, asylee, or nonimmigrant status:

• People who entered the United States illegally;
• People who entered legally in a temporary status and remained after that legal status expired; and
• People who were permitted to enter despite not being admissible as an LPR, asylee, refugee, or nonimmigrant. That typically occurs through the use of parole authority, which permits people to enter the United States temporarily on a case-by-case basis for urgent humanitarian reasons or for significant public benefit. This group includes people who may be awaiting proceedings in immigration court.

Under several laws (such as the one that authorizes Temporary Protected Status) or policies (such as deferred action), the government might choose not to seek the removal of people in the other-foreign-national category for a specified or indefinite period. People in that category might be eligible to apply for employment authorization through various channels (such as by receiving Temporary Protected Status or having applied for asylum). People paroled into the United States are considered to have entered lawfully and to be in the country lawfully during their period of parole.

CBO also projects the civilian noninstitutionalized population age 16 or older, which consists of people who are not members of the armed forces on active duty and who are not in penal or mental institutions or in homes for the elderly or infirm. People held in detention facilities are also excluded from the agency’s projections of the civilian noninstitutionalized population. CBO produces two projections of that population:

• The Census Through 2020 Plus CBO Projection of the civilian noninstitutionalized population uses population estimates produced by the Census Bureau and researchers at the Federal Reserve Board through 2020. After 2020, that population grows in accord with CBO’s estimates or projections of the growth of the total population. CBO uses that series to project the size of the labor force and potential gross domestic product (the maximum sustainable output of the economy).
• The BLS Through 2025 Plus CBO Projection of the civilian noninstitutionalized population incorporates data from the Bureau of Labor Statistics (BLS) through 2025 and uses that year’s estimate as the starting point for CBO’s subsequent projections. CBO uses that series to estimate the unemployment rate and payroll employment numbers that will be reported by BLS.

The total fertility rate represents the average number of children that a woman would have if, in each year of her life, she experienced the birth rates observed or assumed for that year and if she survived her entire childbearing period. (CBO and Social Security’s Board of Trustees estimate that period as ages 14 to 49; the Census Bureau estimates it as ages 14 to 54.)

Life expectancy in a given year is the amount of time a person would expect to survive on the basis of that year’s mortality rates for people of various ages. It is sometimes referred to as period life expectancy.

The mortality rate adjusted for age and sex represents the rate that would be observed if the projected mortality rates by age and sex occurred in a population that had the same age and sex composition as the population in a reference year. CBO uses 2020 as its reference year.

---

1. 1. For more details about eligibility for LPR status, see Office of Homeland Security Statistics, “Immigrant Classes of Admission” (accessed October 16, 2025), https://tinyurl.com/dy2jn95c.

2. 2. For more information about the INA nonimmigrant category, see sec. 101(a)(15) of the Immigration and Nationality Act, 8 U.S.C. § 1101(a)(15) (2024); and Office of Homeland Security Statistics, “Nonimmigrant Classes of Admission” (accessed October 16, 2025), https://tinyurl.com/ms3yh9kv.

About This Document

This volume is one of a series of reports on the state of the budget and the economy that the Congressional Budget Office issues each year. In keeping with CBO’s mandate to provide objective, impartial analysis, the report makes no recommendations.

Daniel Crown and Katherine Keisler-Starkey prepared the report with guidance from Molly Dahl and Julie Topoleski. Jeremy Crimm, Delaney Smith, and Noah Swart contributed to the analysis. Devrim Demirel, Kathleen FitzGerald, Tamara Hayford, Lara Robillard, Emily Stern, and Robert Sunshine (a consultant to CBO) provided comments. Nicholas Johnson and Noah Swart fact-checked the report.

Jeffrey Kling reviewed the report. Christian Howlett edited it, and R. L. Rebach created the graphics and prepared the text for publication. The report is available at www.cbo.gov/publication/61879.

CBO seeks feedback to make its work as useful as possible. Please send comments to communications@cbo.gov.

Phillip L. Swagel

Director

January 2026