Which US states have the highest numbers of undocumented
Executive summary
The states with the largest populations of unauthorized (undocumented) immigrants are consistently California, Texas, Florida, New York, New Jersey and Illinois — a pattern that appears across multiple recent estimates and visualizations [1] [2]. Yet the absolute numbers and rankings have shifted in the 2021–2023 window: California and Texas remain the top two, Florida has been the fastest-growing hub, and methodological differences across Pew, Migration Policy Institute, Pew-linked reporting and state studies produce varying totals that analysts caution must be interpreted carefully [3] [4] [5].
1. Why six states dominate the totals — and which six they are
Most analysts identify the same six states as home to the lion’s share of the unauthorized population: California, Texas, Florida, New York, New Jersey and Illinois, which together accounted for the largest unauthorized immigrant populations in 2021 and still held nearly 8 million in 2023 in Pew’s tabulation cited by Axios [1] [2]. These states combine long-standing immigrant gateways (California, New York, New Jersey, Illinois) with fast-growing destinations (Florida and parts of Texas), concentrating employment, family networks and services that attract and retain unauthorized newcomers [1] [2].
2. The numbers — similar storylines, different totals
Published totals vary by source and year: Migration Policy Institute’s data hub provides state profiles and an 11.4 million estimate for the unauthorized population using pooled ACS and SIPP data adjusted to 2023 weights [4] [6], while other researchers and compilations cite national estimates ranging from roughly 10 million in 2021 to higher provisional figures near 11.7 million or more depending on method [5]. Pew’s more recent analyses show a sharp rise between 2021 and 2023 — from about 10.5 million to 14 million in some reporting — which also affects state-level shares and ranks [7] [2]. Those methodological gaps explain why state rankings can look stable in one dataset and shift noticeably in another [5].
3. Where growth has been fastest: Florida and beyond
Several sources flag Florida as a major growth story: PPIC notes Florida’s undocumented population rose from roughly 0.9 million in 2021 to about 1.6 million in 2023, while Pew-linked reporting and other outlets identify Florida as seeing the largest increase in recent years, driven in part by Venezuelan and Haitian arrivals into South Florida [3] [2] [8]. That surge reduced California’s historical share of the national total even as California still hosts the largest single-state population — reported around 2.25 million undocumented in 2023 by PPIC and other compilers [3].
4. Concentration and dispersion: a changing geography
Undocumented residents remain concentrated — roughly three-quarters were in ten states in some compilations — but researchers emphasize a trend toward dispersion, with growth observed in 32 states between 2021 and 2023 and a declining share in traditional strongholds [9] [2]. This means policy and local impacts are now spread across more jurisdictions, even as the headline top-six list remains a useful shorthand [2] [9].
5. Caveats: methodology, timing and the limits of comparisons
All state tallies rely on statistical imputations and adjustments because the underlying public surveys undercount unauthorized residents; different research teams (MPI, Pew, Center for Migration Studies, CMSNY, DHS OHSS) use distinct samples, weighting and definitions — for example whether to include visa overstays and liminal statuses like DACA and TPS — producing divergent totals and sometimes different state ranks [6] [4] [10] [5]. Reporters and policymakers should therefore treat any single table as indicative not definitive, compare across sources for trends rather than precise counts, and be transparent about which year and method a cited estimate uses [5] [4].