Illegal immigrant population fell by ONE MILLION in first 5 months of Trump term: Center for Immigration Studies

Steven A. Camarota and Karen Zeigler, who authored the report, looked over data from the Census Bureau’s Current Population Survey (CPS), a popularly used dataset that includes legal and illegal immigrants. Their findings suggest a significant reversal of immigration trends, particularly among non-citizens from Latin America who arrived in the US after 1980—a population that strongly overlaps with illegal immigration.

“Based on the CPS,” the authors write, “the total foreign-born population, both in and out of the labor force, declined 957,000 from January to May 2025.” Within this group, non-citizens from Latin America who entered the US after 1980 fell by 1.07 million.

The estimated number of illegal immigrants in the country dropped from 15.8 million in January to 14.8 million in May, according to the report.

The authors say this drop may be due to a combination of Trump’s tough-on-immigration rhetoric, his election victory, and his administration’s efforts to remove as many illegals as possible in a short time. “These results strongly support the idea that the election of Donald Trump, his rhetoric, and high-profile enforcement actions as soon as he took office caused a large number of illegal immigrants to leave the country,” the report states.

Camarota and Zeigler note that the CPS survey does not directly identify illegal immigrants, but by estimating the number of legal immigrants and subtracting that from the total post-1980 foreign-born population, they arrive at a preliminary estimate of the illegal immigrant population.

The study also found that while the number of non-citizens fell significantly, the number of naturalized US citizens increased slightly—another indicator that the decline was driven by departures rather than a slowdown in naturalizations.

The CPS data showed a 3.7 percent drop in the number of foreign-born respondents between January and May.

The researchers caution that their estimate for May is preliminary, noting that some administrative data needed to fully account for legal immigration is not yet available.

They also note that increased fear of enforcement could have made some non-citizens less likely to respond to government surveys, potentially affecting the results.