Fact check: What percentage of illegal aliens file tax returns in the US?

1. Why aggregate tax totals are being used as a proxy — and what they actually show

Multiple studies and reports in the provided material present aggregate tax contributions rather than a direct count of tax return filers among unauthorized immigrants. The Institute on Taxation and Economic Policy (ITEP) and related summaries report nearly $96.7 billion in federal, state, and local taxes paid in 2022, and Budget Lab estimated $66 billion in federal income and payroll taxes for 2023, with breakdowns into payroll and income components ^{[2] [1] [3]}. These dollar figures mean many unauthorized workers either have payroll taxes withheld, use ITINs to file returns, or pay sales and property taxes indirectly, but they do not translate cleanly into a precise percentage of individuals filing tax returns, because payments can be made through employer withholding, ITIN-based filings, or informal arrangements.

2. Older direct estimates suggest a broad range, but they are dated

A frequently cited historical estimate from the Congressional Budget Office (CBO) suggested that between 50% and 75% of unauthorized immigrants pay some form of federal income or payroll tax, a range that is often invoked to indicate high tax participation ^[3]. That CBO figure originates from older analyses and reflects methodologies and labor-market conditions that have changed over time. While it provides a useful benchmark showing that it is plausible a majority of unauthorized immigrants pay taxes, the provided material does not include a newer, directly comparable CBO-style estimate that confirms whether that 50–75% range still holds in the 2020s amid shifting enforcement policies, labor patterns, and ITIN usage ^[3].

3. ITIN usage and payroll-withholding create partial visibility

The IRS’s issuance of Individual Taxpayer Identification Numbers (ITINs) enables many unauthorized immigrants to file returns, and several sources emphasize that ITIN use and payroll withholding are key channels through which taxes are paid by undocumented workers ^{[4] [5]}. Reports highlight that fear of enforcement or data sharing can deter filings, which complicates measurement: underreporting or avoidance in response to policy changes may temporarily depress filings even when economic activity continues ^[6]. Therefore, aggregate tax receipts rising or falling can reflect changes in filing behavior, labor force participation, or enforcement messaging, not solely the underlying count of undocumented taxpayers.

4. Recent policy debates and enforcement rhetoric likely change filing behavior

Contemporary news analyses point out that rhetoric about IRS-ICE data-sharing and enforcement initiatives has produced heightened fear among undocumented communities, which could reduce tax filing even among those who normally file using ITINs or employer-reported wages ^{[1] [6]}. These reports from 2024–2025 tie policy signaling to practical effects: while aggregate tax estimates remain substantial, short-term declines in filing or changes in tax payment channels could occur, meaning static percentages from older studies may overstate current filing rates if fear reduces voluntary filings or drives more income off-the-books.

5. Methodological limits explain why a single percentage is elusive

The provided sources uniformly show that direct measurement is difficult: tax records do not always reveal immigration status; payroll taxes can be paid without individual returns; and ITIN filings do not capture everyone who pays sales or property taxes indirectly ^{[1] [5] [7]}. Thus, researchers rely on indirect estimation—combining labor force, wage, and tax data—to produce dollar estimates and broad percentage ranges. These methods yield consistent evidence that unauthorized immigrants contribute meaningfully to tax receipts, but they also produce uncertainty around an exact, current percentage of unauthorized individuals who file individual income tax returns.

6. What the different sources emphasize—and possible agendas to watch

Think tanks and advocacy organizations emphasize different aspects: ITEP and Budget Lab frame large tax contributions to argue undocumented immigrants are net tax payers at certain levels and to caution against policies that deter filing ^{[2] [1]}. Reporting on IRS-ICE data-sharing highlights confidentiality and deportation concerns, which can underscore civil-liberties and immigrant-protection agendas ^[6]. The CBO-style estimates are presented as neutral benchmarks but are older. Readers should note that organizational priorities can shape emphasis on aggregate dollars versus filing rates, which affects interpretations of how many unauthorized immigrants file tax returns.

7. Bottom line and what would resolve the uncertainty

The evidence in the provided material supports the conclusion that a substantial portion of unauthorized immigrants pay federal, state, or local taxes, and historical estimates put the share who pay income or payroll taxes in the majority range (about 50–75%), but no single current source here supplies a precise, up-to-date percentage of those who file individual tax returns ^{[3] [2] [1]}. Resolving the question would require recent, de-identified IRS-verified analysis that links tax-filing behaviors to immigration-status estimates—or updated CBO/academic studies using current labor, ITIN, and withholding data that explicitly report a filing-rate percentage.