The Undocumented Population in the United States Increased to 12.2 Million in 2023

By Robert Warren

In 2023, the US undocumented population reached 12.2 million, exceeding the previous high of 12.0 million in 2008. This report provides estimates of the undocumented population in 2023 based on data collected in the Census Bureau’s American Community Survey (ACS). The report focuses on trends in annual population growth from 2013 to 2023 for the total population and for 17 countries or areas of origin. It also describes trends in the undocumented population in the six states with the largest undocumented population in 2023.

The CMS estimates of undocumented residents include immigrants in the Deferred Action for Childhood Arrivals (DACA) and Temporary Protected Status (TPS) programs, and the estimates include most of the people that have entered asylum backlogs or received humanitarian parole status since 2021. The estimates were derived using previous CMS estimation procedures except that higher undercount rates were used to estimate the number of undocumented residents that arrived after 2020.

Adjustment for undercount was increased for post-2020 arrivals to account for the unusually large flow across the US/Mexico border in recent years and because relatively more migrants resided in group quarters1 where enumeration can be difficult. The CMS methodology is summarized after the following section, and information about undercount rates for recent arrivals is shown in the Appendix.

Journal on Migration and Human Security, May 2025, 8p.