In 2026 how many undocumented or illegals were in the USA?
Executive summary
Mainstream, peer-reviewed and government-linked estimates in recent years place the number of undocumented (also described as unauthorized or illegal) immigrants in the United States in a band roughly between about 11 million and 14 million, but contested methodologies and outlier studies put the figure as low as ~11 million and as high as more than 20 million; no definitive, single 2026 headcount exists because of measurement limits and rapid policy-driven flows [1] [2] [3] [4]. Federal budget and migration forecasts in late 2024–2026 also point to sharply lower net migration and heightened removals that would likely shrink or slow the undocumented population in 2026 relative to the 2021–2023 surge, but they do not produce a single, precise 2026 tally [5] [6].
1. Mainstream estimates: an 11–14 million consensus with nuance
Major research centers and demographic tools converge near the low-teens: the Immigration Research Initiative summarizes three leading estimates that round to roughly 11 million undocumented at the national level using data through 2022 (Center for Migration Studies, Pew, Migration Policy Institute methods) [1]. Pew Research’s updated analysis incorporated revised Census migration data and reported the unauthorized population reached a record 14 million in 2023 — the largest two‑year jump in their series — reflecting both arrivals and the Census Bureau’s changed international-migration adjustments [2] [7]. The Migration Policy Institute and Center for Migration Studies produce similar but slightly different estimates in the low‑to‑mid teens depending on methodology and the treatment of undercounts [8] [3].
2. Why the numbers differ: methods, undercounts, and who’s counted
Differences trace to methodology: residual approaches that net out legal arrivals from total foreign‑born counts, survey-based adjustments for undercounted immigrants, and demographic models that add operational enforcement data yield divergent totals [9]. Researchers explicitly note undercounts of immigrants in surveys and the need for country-specific adjustments, and some groups include recently paroled or otherwise temporarily admitted people in their counts while others do not, producing materially different results [1] [9] [7].
3. Outliers and political estimates: very different pictures
A handful of studies and advocacy organizations present much higher totals. A 2018 demographic-model paper argued for roughly 22.1 million undocumented — a result based on operational and demographic modeling that many scholars dispute [4]. On the opposite pole, advocacy groups with restrictive-immigration agendas, such as FAIR, have produced an 18.6 million estimate for 2025, citing alternative interpretations of removal and net‑flow data [10]. These outliers matter politically because they drive public perceptions and policy rhetoric, but they rest on assumptions and data choices that mainstream demographers treat as contested [4] [10].
4. Policy, enforcement and 2026 dynamics: why numbers could shift quickly
Analysts tracked a major policy shift in 2025 that reduced net arrivals and increased removals; Brookings projected a sharp slowdown in net migration through 2026, and the Congressional Budget Office estimated materially smaller net immigration for 2026 relative to earlier projections — suggesting the undocumented population could stabilize or decline in 2026 compared with its 2023 peak, though the agencies stop short of a firm 2026 headcount [5] [6]. The CBO also quantified expected increases in removals and voluntary departures through 2026–2030, indicating enforcement could lower the undocumented population further but without producing a single census-like figure [6].
5. Bottom line: a range, not a single number
Based on the best-accepted sources and recent updates, credible estimates for the U.S. undocumented population in the mid‑2020s cluster between about 11 million and 14 million, with some analysts and advocacy groups arguing for substantially higher totals up to ~18–22 million depending on methods and definitions; precise confirmation for 2026 is not available because of measurement lags, differing inclusion rules, and rapid policy-driven flow changes [1] [2] [3] [10] [4] [6]. Researchers and federal analysts agree on one point: methodological choices and evolving policy make single-year blunt counts uncertain, so reporting should present ranges and explain the assumptions behind any headline number [9].