Fact check: How many undocumented immigrants are currently enrolled in Medicaid in the US?

Executive Summary — Short Answer Up Front: The available evidence shows undocumented immigrants are not eligible for federally funded Medicaid; there is no reliable count of undocumented people “enrolled” in standard Medicaid programs because federal rules exclude them. States can and do use Medicaid funds to reimburse hospitals for emergency care under Emergency Medicaid, but that program represents less than 1% of total Medicaid spending, and spending figures — not enrollment counts — are what is measurable in federal reports ^{[1] [2] [3]}.

1. Why there’s no firm enrollment number and what the data actually measure

Federal Medicaid eligibility rules limit regular Medicaid to U.S. citizens and certain lawfully present immigrants, which means undocumented immigrants are not eligible for federally funded enrollment; consequently, no federal enrollment tally exists for undocumented people in standard Medicaid rolls. Public analyses and federal reports therefore focus on Emergency Medicaid reimbursements — payments to hospitals for emergency care provided to people who meet Medicaid financial eligibility but are ineligible due to immigration status — rather than counts of enrollees ^{[3] [1]}. The Congressional Budget Office and other analysts quantify spending on Emergency Medicaid and emergency care reimbursements, showing that federal and state Medicaid programs record dollars spent for emergency services but do not reflect “enrollment” of undocumented immigrants in standard Medicaid programs ^{[2] [4]}.

2. What the spending numbers tell us about utilization and scale

Between fiscal years 2017 and 2023, federal analyses indicate about $27 billion was spent on Emergency Medicaid for noncitizen immigrants, a relatively small share of total Medicaid expenditures, and federal summaries put Emergency Medicaid spending at under 1% of overall Medicaid spending in that period. Those spending figures reveal that health systems regularly seek Medicaid reimbursement for emergency services and labor-and-delivery care for people ineligible for full Medicaid coverage, but they do not convert directly into counts of undocumented individuals or indicate comprehensive coverage of chronic or preventive care needs ^{[2] [1]}. Policymakers and researchers therefore use expenditure data as a proxy for acute care utilization rather than a measure of enrollment.

3. State-by-state patches and why local policy matters

States vary widely in how they fill coverage gaps for undocumented residents: many states provide Emergency Medicaid for acute care and childbirth, some states extend state-funded programs that cover certain primary or prenatal services for undocumented people, and 37 states plus DC offer Emergency Medicaid specifically for emergency care as of mid-2025. These state-level programs complicate any national enrollment estimate because some coverage comes from state-funded plans outside federal Medicaid rolls, and these programs are heterogeneous in eligibility, scope, and reporting practices ^{[5] [4]}. Researchers note that coverage gaps persist for chronic conditions and cancer treatment where emergency-only reimbursements do not substitute for continuous care ^[5].

4. Noncitizen coverage patterns that are related but distinct from undocumented populations

Analyses of noncitizen populations show that many lawfully present immigrants face waiting periods or restrictions and that only a minority of noncitizens are covered by Medicaid or CHIP — for example, one modeling exercise estimated 15.7% of noncitizens were covered by Medicaid/CHIP in 2024, and about 8.7 million noncitizens remained uninsured. Those figures include a mix of lawfully present immigrants and excluded undocumented people, so they are useful for context but do not isolate undocumented enrollment in Medicaid because federal rules treat these groups differently ^[6]. Recent policy changes and debates over eligibility for different immigrant categories further complicate year-to-year comparisons ^[7].

5. Bottom line for claim verification and where uncertainty remains

Claim: “How many undocumented immigrants are currently enrolled in Medicaid?” — Verdict: There is no authoritative count because federal law prohibits undocumented immigrants from enrolling in standard federally funded Medicaid, and available federal data capture Emergency Medicaid spending rather than enrollment. The clearest, verifiable metrics are expenditure-based — Emergency Medicaid reimbursement totals and state program enrollments where states explicitly fund coverage — not a single national enrollment figure for undocumented people. Analysts and advocates point to spending and utilization data to illustrate the scale of acute-care use, while state-managed programs create fragmented pockets of coverage that are tracked separately ^{[1] [2] [5]}.