Fact check: What are the estimated costs of providing healthcare coverage to undocumented immigrants in the US?

1. The headline numbers that circulate — what they actually measure and why they differ

Public figures often cited — such as the claim that Medicaid emergency spending on undocumented immigrants exceeded $16.2 billion since the Biden administration began — come from selective readings of CBO-related reporting that focus on emergency Medicaid outlays, not full coverage costs or per‑capita comparisons. Those figures reflect spending on emergency services that are billable under existing rules for non‑citizens and are presented as cumulative totals over multiple years, so they are not direct estimates of the cost to provide comprehensive health insurance to all undocumented residents ^{[4] [1]}. Other datasets tally emergency Medicaid across broader timeframes and produce different totals ^[1]. The difference between emergency-only spending and full Medicaid‑level benefits is central: emergency Medicaid is a narrow slice and typically far cheaper per enrollee than comprehensive coverage ^{[3] [2]}.

2. What rigorous agencies say — CBO findings and limitations

The Congressional Budget Office and associated analyses repeatedly caution that measuring the budgetary effect of unauthorized immigrants is complex and context-dependent; a 2007 CBO study underscored difficulties in aggregating state and local fiscal impacts, while more recent CBO correspondence quantified $27 billion in federal and state emergency Medicaid spending for non-U.S. nationals from 2017–2023, illustrating the scale of emergency care costs but not the price tag of providing full benefits ^{[5] [1]}. These CBO outputs are conservative, methodologically transparent estimates focused on observed program outlays rather than predictive modeling of policy changes, and they highlight that projections shift dramatically depending on assumptions about eligibility expansion, utilization rates, and cost-sharing rules ^{[6] [7]}.

3. Per‑person use: immigrants use less care on average, which changes the math

Multiple analyses find that immigrants, including undocumented people, use less healthcare and have lower average annual healthcare expenditures than U.S.-born citizens; one comparison put immigrant per‑capita spending at about $4,875 versus $7,277 for U.S.-born individuals, roughly two‑thirds the latter figure ^[2]. If policymakers modeled full coverage enrollment using immigrant utilization patterns rather than U.S.-born averages, projected costs per enrollee would be materially lower than simple pro rata estimates. That lower utilization is a commonly omitted consideration in high‑end cost claims and is central to any accurate fiscal estimate of extending comprehensive benefits.

4. State experiments and targeted studies show partial fiscal pictures, not national totals

California’s initiative to commission a study of Medi‑Cal and Covered California expansions for undocumented residents exemplifies how state‑level analysis can quantify fiscal impacts locally but not substitute for a national estimate ^[8]. State reports and analyses often capture short‑term administrative costs and program uptake dynamics while leaving unanswered the question of national cost distribution across federal, state, and local budgets. These focused studies are valuable for policy design because they reveal cost drivers such as enrollment churn, preventive care uptake, and uncompensated care reductions, yet they do not produce a single U.S. dollar figure for nationwide comprehensive coverage ^[8].

5. Emergency spending is a small share of total Medicaid outlays, mitigating some budget fears

Analyses documenting that emergency Medicaid spending represented about 0.4% of total Medicaid expenditures in 2022 and translated to roughly $9.63 per resident reinforce that emergency care for undocumented immigrants is a small slice of overall program spending ^[3]. That share indicates that arguments framing undocumented immigrants as a major driver of Medicaid cost growth are inconsistent with observed aggregate spending patterns. Even when cumulative emergency outlays appear large in absolute terms, their proportion of total Medicaid spending is modest, and expanding non‑emergency coverage could shift costs from emergency to preventive and primary care, potentially lowering avoidable high‑cost hospitalizations ^{[3] [2]}.

6. Bottom line: no single definitive national price tag — but informed bounds exist

There is no universally accepted single dollar estimate for providing comprehensive healthcare coverage to all undocumented immigrants because estimates hinge on eligibility design, enrollment rates, per‑person utilization, federal versus state cost shares, and behavioral responses to coverage. The available evidence provides bounded insights: emergency Medicaid spending has been measured in the tens of billions over recent multi‑year windows ^{[1] [4]}, immigrants’ per‑capita healthcare use is lower than U.S.-born averages ^[2], and emergency care is a small fraction of total Medicaid outlays ^[3]. Policymakers seeking a national price should commission scenario‑based CBO‑style modeling that explicitly states assumptions about coverage scope, uptake, and cost containment; piecing together current studies yields plausible but widely varying fiscal outcomes.