What impact did Mexico and Central American demographic changes have on U.S. undocumented immigrant levels since 2010?
Executive summary
Mexico’s share of the U.S. unauthorized population fell from 62% in 2010 to about 40% by 2023, while Central American nationalities (notably Guatemala, Honduras, El Salvador) and South America together accounted for the bulk of the recent growth in undocumented residents (MPI, CMS, PSU) [1] [2] [3]. Multiple analyses attribute this shift to demographic and economic changes in Mexico (slower population growth and improved conditions) and intensified displacement and migration pressures in Central and South America after 2019–21; the result has been both a decline in Mexican-origin undocumented stock and rapid increases from Central America since 2019 [4] [2] [3].
1. A shrinking Mexican share, not an empty border
Data-driven estimates show Mexico remained the largest origin country in absolute terms by 2023, but its proportion of the unauthorized population fell sharply—from 62% in 2010 to about 40% in 2023—reflecting a relative decline rather than a disappearance of Mexican migration (Migration Policy Institute; PSU; El País) [1] [3] [5]. The Center for Migration Studies (CMS) finds the undocumented population from Mexico declined by roughly 630,000 over a recent six-year window while “all other” country totals rose, highlighting that declines in Mexican-origin undocumented residents were offset by increases from other places [2].
2. Central America: the engine of recent growth
Multiple tabulations attribute the bulk of the undocumented-population increase since 2019 to Central America: CMS reports Central American undocumented numbers rose by about 1.12 million in one recent period, and PSU/MPI note Central American-origin unauthorized immigrants expanded substantially between 2019 and 2023 [2] [3] [1]. Migration Policy Institute and related analyses single out Guatemala, Honduras and El Salvador as fast-growing origin groups, with Guatemalans’ share, for example, rising markedly within the undocumented mix [5] [6].
3. Why Mexico’s numbers fell: demography and domestic change
Analysts tie Mexico’s reduced outflow to long-term demographic shifts—falling birth rates and slowed population growth—and improving economic conditions at home that reduced push factors for migration, so fewer would‑be migrants departed (Brookings; PBS) [7] [4]. Migration scholars have previously documented how Mexican return migration and lower net flows since the mid-2000s have reshaped the Mexican-born contingent in the U.S.; contemporary reporting repeats that trend as a key explanation for Mexico’s shrinking share of the unauthorized population [4] [7].
4. Why Central American numbers rose: displacement, violence and labor demand
Sources point to a combination of push factors—violence, insecurity, economic crisis and political repression across parts of Central and South America—and pull factors, including U.S. labor-market recovery after the COVID downturn, that together drove larger flows northward beginning around 2021 (MPI; PSU; PBS) [1] [3] [4]. MPI and PSU emphasize that worsening conditions in sending countries plus expanded opportunities in the U.S. explain why Central American-origin undocumented populations expanded rapidly after 2019 [1] [3].
5. Different migration modalities: border encounters vs. visa overstays
Analysts note the composition of unauthorized migration changed: historically dominated by Mexican border crossings, the recent rise involves more asylum seekers, varied nationalities (Central and South America, plus countries farther afield), and different pathways such as humanitarian claims or irregular land/sea journeys rather than only clandestine river crossings (PBS; MPI) [4] [1]. This matters for policy because enforcement and humanitarian responses differ depending on whether flows are concentrated by origin, mode, or legal claiming behavior [4].
6. Measurement caveats and competing estimates
Estimates vary by method and source: MPI reports roughly 13.7 million unauthorized immigrants mid‑2023 and highlights origin shifts; CMS produced a provisional 11.7 million July‑2023 figure emphasizing Mexican declines and Central American gains; Pew and other groups offer alternate counts and time frames, so absolute totals differ while the pattern of declining Mexican share and rising Central American presence recurs across analyses [8] [2] [9]. All sources warn that undercounts, departures (voluntary emigration, removals, deaths, status adjustment), and differing survey frames complicate precise tallies [2] [7].
7. Policy implications and political uses of the trend
Reporting shows the shift has been seized by different actors for competing narratives: advocates point to new humanitarian needs and the heterogeneity of origins; enforcement-focused actors emphasize record border encounters and call for border hardening [1] [10]. Observers also note that changes in Mexican enforcement (e.g., Mexico interdicting migrants) and U.S. policy shifts can quickly reshape routes and counts, meaning trends remain politically and operationally sensitive [11] [10].
Limitations: available sources do not mention every causal channel (e.g., detailed fertility-by-age breakdowns or micro-level household decisions), and absolute population totals differ across organizations; the reporting above relies on the MPI, CMS, PSU/academic summaries, PBS, Brookings and related coverage provided in the search results [1] [2] [3] [4] [7].