Fact check: What are the top countries of origin for undocumented immigrants in the US as of 2025?

1. Why Mexico still tops the list — but with a smaller footprint

Multiple analyses show Mexico accounts for the largest single national origin of unauthorized immigrants, but its absolute number and percentage have fallen from 2010s peaks. Estimates cite roughly 4.0–4.2 million Mexico-born unauthorized residents in earlier multi-year snapshots (2019–2022), representing between about 37% and 41% of the unauthorized total in those estimates ^{[3] [1] [4]}. The Migration Policy Institute and other analyses emphasize a long-term decline in the Mexican share even as the total unauthorized population fluctuated, driven by changed migration pressures, border enforcement, and demographic shifts in origin countries ^{[4] [2]}.

2. Central America rising: Guatemala, Honduras, El Salvador show up repeatedly

Across 2019–2025 reports, Guatemala, Honduras, and El Salvador are consistently among the top origins after Mexico, reflecting sustained asylum-seeking and irregular migration from northern Central America. Several sources list those three countries immediately behind Mexico in rank-orderings and note growing relative shares during 2019–2023 and into early 2025 estimates ^{[3] [1] [2]}. These countries’ presence in multiple analyses underscores common drivers—violence, poverty, and climate-related stress—reported by researchers, even as exact counts vary with methodology and timing ^[2].

3. South America’s growing footprint: Venezuela, Colombia, Ecuador, Brazil

Recent MPI and other analyses point to Venezuela, Colombia, Ecuador and Brazil as important and growing contributors to the unauthorized population, particularly in the 2019–2023 period when Venezuelan displacement and broader South American out-migration accelerated. A February 2025 MPI report explicitly lists Venezuela, Colombia, Ecuador and Brazil among the top origins contributing to a multi-million rise in unauthorized residents between 2019 and 2023 ^[2]. This shift increases the geographic diversity of the unauthorized population, contrasting with the earlier Mexico-dominated profile ^[4].

4. Why different sources list different top-five lineups

Discrepancies across studies arise from timing (2019 vs. 2022 vs. 2025), definitions (unauthorized vs. all foreign-born), and estimation methods (survey adjustments, administrative data, modeling). Pew’s broader immigrant snapshots emphasize overall foreign-born origin patterns—showing Mexico, India, China, Philippines, and Cuba among all immigrants—while unauthorized-focused studies restrict to noncitizen, non‑legal populations and thus highlight Latin American origins ^{[5] [3] [4]}. The studies’ publication dates also matter: later MPI analyses capture the South American surge not visible in older estimates ^[2].

5. Magnitude and uncertainty: ranges, not precise headcounts

Authors report ranges: roughly 10–14 million unauthorized immigrants in different studies’ snapshots, with Mexico contributing about 4 million in several estimates but with credible ranges above and below that number depending on year and methodology ^{[6] [3] [1]}. MPI’s 2025 reporting documents a growth of about 3 million unauthorized people from 2019–2023, amplifying uncertainty about current shares and ranks in 2025 ^[2]. Analysts warn that enforcement, migration policy, and rapid flows can alter composition quickly, so point estimates must be read as provisional ^{[6] [7]}.

6. Contrasting perspectives and possible agendas behind sources

Different institutions carry identifiable orientations that shape emphasis: advocacy and research centers (e.g., American Immigration Council, MPI) focus on detailed origin-country breakdowns and policy implications, while demographic centers (e.g., Pew) situate unauthorized flows within broader foreign-born trends and population change. Each frames findings to support policy arguments—either emphasizing humanitarian drivers, economic roles, or enforcement impacts—so analysts must triangulate across types of organizations to reduce single-source bias ^{[1] [4] [7]}.

7. What this means for readers seeking a 2025 “top countries” list

To report a defensible 2025 ranking, state that Mexico remains first, followed by a cluster of Central American countries (Guatemala, Honduras, El Salvador) and growing South American origins (Venezuela, Colombia, Ecuador, Brazil), with precise order and counts varying by dataset and date. Use recent MPI and American Immigration Council figures for unauthorized-focused rankings and Pew for context on the entire immigrant population; always note the estimate year because composition shifted markedly between 2019 and early 2025 ^{[2] [3] [5]}.

8. Bottom line for policy and reporting: emphasize uncertainty and change

Reliable public communication should present Mexico-first but diversifying as the concise takeaway, quantify ranges rather than single-point counts, and cite the estimate year and method. The balance of evidence through 2025 shows a clear trend toward greater Central and South American representation among unauthorized arrivals while Mexico’s relative dominance declines; further changes are likely as migration drivers and enforcement policy evolve, making ongoing, multi-source monitoring essential ^{[3] [2] [7]}.