What percentage of US healthcare spending is attributed to undocumented immigrants?

1. Numbers on the table: Why the share looks tiny and how scholars measure it

Scholarly and policy summaries report that undocumented immigrants represent a small fraction of U.S. healthcare spending, but that conclusion depends on what is counted. One frequently cited estimate places undocumented immigrants at about 1.4% of total U.S. health‑care spending, drawn from academic analyses referenced in commentary on immigrants’ payments and expenditures ^[1]. Other calculations focus narrowly on federal emergency care paid through Medicaid and find federal spending on emergency services for undocumented immigrants totaled $974 million in 2016, representing 0.03% of total national health expenditures or 0.2% of Medicaid expenditures, illustrating widely different shares when the denominator or spending category changes ^[2]. These differences show that measurement choices—total national expenditures vs. particular federal programs—drive headline percentages ^{[1] [2]}.

2. Health‑use patterns: Lower utilization and per‑person spending among immigrants

Multiple reviews indicate that immigrants, including undocumented people, generally have lower per‑capita health expenditures and use fewer services than U.S.‑born residents. Analyses report average annual per‑capita expenditures of about $4,875 for immigrants versus $7,277 for U.S.‑born citizens, which reduces immigrants’ share of aggregate spending relative to their population share ^[4]. Commentaries note that undocumented people face eligibility limits for Medicaid and Marketplace coverage, which suppresses utilization and shifts much care to emergency settings or uncompensated care, further complicating the arithmetic of “who pays and who uses” ^{[4] [5]}. The lower utilization pattern is a consistent finding across sources, and it directly limits undocumented immigrants’ contribution to total health spending ^{[4] [1]}.

3. Fiscal flows: Taxes paid versus benefits received—some surprising net contributions

Analyses show unauthorized immigrants often contribute more in payroll taxes to programs like Medicare than they withdraw, producing net positive balances in some timeframes. One synthesis finds a $35.1 billion surplus to Medicare from 2000–2011 attributable to unauthorized immigrants, suggesting they help support trust funds despite limited eligibility for benefits ^[3]. Parallel work highlights that only a small share of unauthorized immigrants incur publicly financed health expenditures (about 7.9% in one estimate), with low per‑person publicly financed costs averaging $140 annually, which supports the conclusion that undocumented populations are not a large net drain on publicly financed health spending ^{[3] [2]}. These fiscal flow measures depend on tracking tax contributions, use of employer‑sponsored insurance, and uncompensated care allocations ^[3].

4. Policy effects: Eligibility rules change the spending picture

Policy constraints markedly alter who uses which services and who shows up in spending tallies. Federal rules that exclude undocumented immigrants from Medicaid and Marketplace coverage reduce their recorded participation in public programs and push care into emergency or uncompensated settings ^{[4] [5]}. Recent fact‑checks around 2025 legislative changes clarified that some claims confusingly conflated lawfully present immigrants with undocumented people, affecting public narratives about who would lose coverage and how aggregate spending would shift ^[6]. The policy context—eligibility ceilings, state decisions, and legislative changes—therefore shapes both utilization and the accounting of costs and contributions ^{[4] [6]}.

5. Contrasting estimates and methodological tradeoffs—read the footnotes

Different studies produce different headline percentages because they use distinct methods: some count total national health expenditures, others count federal program outlays or emergency care only; some attribute employer‑sponsored insurance and tax flows to the undocumented population, while others focus only on public spending. The 1.4% figure appears in academic syntheses cited in commentary as an estimate of undocumented immigrants’ share of total spending, whereas narrower federal calculations produce fractions of a percent for specific programs ^{[1] [2]}. Analysts and advocates can emphasize different metrics to support divergent narratives—either that undocumented people are a modest net contributor or that they impose avoidable costs—so examine the denominator and program scope to understand what a given percentage actually means ^{[1] [2]}.

6. Bottom line and what remains uncertain

The evidence provided here converges on a clear bottom line: undocumented immigrants account for a very small share of U.S. health‑care spending, typically well under a few percent of total expenditures, and often much less when looking at specific federal programs; they also exhibit lower per‑capita spending and contribute taxes that offset some program costs ^{[1] [2] [3]}. Remaining uncertainties stem from patchy data on undocumented populations, differing accounting choices, and evolving policy landscapes that change eligibility and reporting. Readers should treat any single percentage as contingent on those methodological decisions and check whether the figure refers to total national spending, Medicaid outlays, emergency care, or net fiscal impact, because that choice determines whether a share looks large or negligible ^{[4] [2]}.