Undocumented immigrants paying taxes in the United States follow the same federal rules as anyone else who lives and earns income here: if your income crosses the filing threshold, you owe a return, and the IRS issues an Individual Taxpayer Identification Number (ITIN) so you can file without a Social Security number. Immigration status doesn’t change the obligation. What it changes is which identification number goes on the return, which credits you can claim, and, since 2025, how much of your filing information stays walled off from immigration enforcement.
Whether You Have to File
Federal law requires every individual whose gross income meets or exceeds a set threshold to file a return, regardless of citizenship. The threshold tracks the standard deduction, which the IRS adjusts each year. For 2026, that’s $16,100 for a single filer, $32,200 for married couples filing jointly, and $24,150 for a head of household.1Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 Below those amounts you generally aren’t required to file, but you may want to if you’re owed a refund.
The filing rule at 26 U.S.C. § 6012 applies to “every individual” over the threshold and says nothing about citizenship or legal status.2Office of the Law Revision Counsel. 26 USC 6012 – Persons Required to Make Returns of Income Section 1 of the same title imposes the income tax itself on every individual’s taxable income.3Office of the Law Revision Counsel. 26 USC 1 – Tax Imposed
Whether the IRS treats you as a U.S. tax resident turns on physical presence, not paperwork. Under the Substantial Presence Test, you’re a resident for tax purposes if you were in the country at least 31 days in the current year and at least 183 days over a three-year period, counting all current-year days, one-third of last year’s days, and one-sixth of the year before that.4Internal Revenue Service. Substantial Presence Test Anyone who has lived here for a year or more will usually clear it easily.
Filing Without a Social Security Number
If you can’t get an SSN, the IRS issues an ITIN so you can file. It’s a nine-digit number used only for federal tax purposes. You apply by submitting Form W-7 together with a completed federal tax return, as one package.5Internal Revenue Service. Individual Taxpayer Identification Number (ITIN)
Documents You’ll Need
The IRS accepts 13 types of documents to prove identity and foreign status. A valid passport is the simplest choice because it satisfies both on its own. Without a passport, you need at least two documents from the approved list, with at least one showing your photo.
- Documents that prove both identity and foreign status on their own: USCIS photo ID, U.S. visa, national identification card, foreign military ID, foreign voter registration card.
- Identity only: U.S. driver’s license, U.S. state ID card, U.S. military ID, foreign driver’s license.
- Both identity and foreign status with limitations: civil birth certificate, medical records (for dependents under 6), school records (for dependents under 24 who are students).
All documents must be originals or certified copies from the issuing agency. Notarized copies aren’t accepted. Everything must be current and unexpired, except civil birth certificates.6Internal Revenue Service. Instructions for Form W-7
How to Submit the Application
There are three ways to file the W-7 package:
- By mail to the IRS ITIN Operation at P.O. Box 149342, Austin, TX 78714-9342. Original documents (or certified copies) go with the package, and the IRS returns them within 60 days.
- Through a Certifying Acceptance Agent (CAA), who is authorized to review and certify your documents in person so you don’t have to mail originals. This is often the better option if surrendering a passport or national ID for weeks isn’t practical.
- In person at an IRS Taxpayer Assistance Center that handles ITIN applications, bringing your documents for verification on the spot.
Processing runs about seven weeks under normal conditions, up to 11 during peak filing season or when filing from overseas.6Internal Revenue Service. Instructions for Form W-7 Once approved, you’ll receive a letter with the number to use on future returns.
Keeping the ITIN Active
An ITIN doesn’t last forever. If it isn’t used on at least one federal tax return during three consecutive tax years, it expires on December 31 of that third year.7Internal Revenue Service. How to Renew an ITIN File in 2024 but skip 2025, 2026, and 2027, and the number is dead at the end of 2027.
To renew, submit a new Form W-7 with the “Renew an existing ITIN” box checked and your identity documents. Spouses and dependents renewing to be claimed for a tax benefit must be listed on an attached return. If your legal name has changed, include documentation such as a marriage certificate or court order.7Internal Revenue Service. How to Renew an ITIN Filing with an expired ITIN won’t get the return rejected, but any refund will wait until the renewal processes.
Self-Employment Tax and Quarterly Payments
Many undocumented workers are paid as independent contractors rather than employees, and the IRS is explicit that ITIN holders owe self-employment tax on net earnings of $400 or more. The rate is 15.3%, split into 12.4% for Social Security and 2.9% for Medicare.8Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) That’s double what an employee pays because you cover both the worker’s share and the amount an employer would normally match.
Self-employed filers usually can’t wait until April to settle the whole bill. If you expect to owe $1,000 or more after any withholding and credits, you’re required to make quarterly estimated payments. For 2026, they’re due April 15, June 15, September 15, and January 15, 2027.9Internal Revenue Service. 2026 Form 1040-ES Missing a deadline triggers an underpayment penalty. Use Form 1040-ES to figure and submit each payment.
Which Credits ITIN Filers Can and Can’t Claim
The tax code draws sharp lines based on the type of identification number on the return. Some of the largest federal credits are off-limits when you file with an ITIN.
The Earned Income Tax Credit is the biggest loss. It requires that you, your spouse, and any qualifying children all have valid Social Security numbers. An ITIN doesn’t count under 26 U.S.C. § 32(m).10Office of the Law Revision Counsel. 26 USC 32 – Earned Income For a family that would otherwise qualify, this can mean thousands of dollars in refundable credit forgone each year.
The Child Tax Credit works the same way. Under 26 U.S.C. § 24(h)(7), each qualifying child must have an SSN issued before the return’s due date.11Office of the Law Revision Counsel. 26 US Code 24 – Child Tax Credit A child with only an ITIN doesn’t qualify for the full credit.
Not everything is closed off. Dependents who have an ITIN or SSN and don’t qualify for the Child Tax Credit may still qualify for the Credit for Other Dependents, worth up to $500 per dependent.12Internal Revenue Service. Understanding the Credit for Other Dependents Education credits, including the American Opportunity Tax Credit and the Lifetime Learning Credit, are available to taxpayers and students filing with an ITIN and can offset tuition costs meaningfully.13Internal Revenue Service. Education Credits – AOTC and LLC
Privacy: What Changed in 2025
The long-standing rule is that 26 U.S.C. § 6103 keeps tax return information confidential and generally bars the IRS from sharing it with other agencies.14Office of the Law Revision Counsel. 26 US Code 6103 – Confidentiality and Disclosure of Returns and Return Information That was a core reason many undocumented filers felt comfortable submitting returns. It shifted in 2025.
In April 2025, the IRS and Immigration and Customs Enforcement signed a Memorandum of Understanding letting ICE submit names and addresses for cross-verification against tax records. The cited legal basis was § 6103(i)(2), which allows disclosure of certain “return information” for use in criminal investigations. Four organizations sued to block it.15Congress.gov. CRS Legal Sidebar – Centro de Trabajadores Unidos v. Bessent
A federal district judge denied a preliminary injunction, finding the government likely to succeed on the argument that the MOU fits the statute’s exception for nontax criminal investigations. The court held that a taxpayer’s name, address, and taxpayer identification number are not protected “taxpayer return information.” The case was on appeal to the D.C. Circuit as of that ruling.
Practically, filing a return still doesn’t hand ICE the contents of your return. But if ICE already has your name and address from another source, the MOU may allow the IRS to confirm address information on file. This is an evolving area of law. Anyone weighing the risk should talk to an immigration attorney before deciding whether to file.
What Happens If You Don’t File
Skipping a return carries its own consequences. The failure-to-file penalty is 5% of the unpaid tax for each month or partial month the return is late, capped at 25%.16Internal Revenue Service. Failure to File Penalty Five months late and you’re already at the ceiling.
Willful tax evasion is a felony. Under 26 U.S.C. § 7201, conviction can bring a fine of up to $100,000 and up to five years in prison.17Office of the Law Revision Counsel. 26 USC 7201 – Attempt to Evade or Defeat Tax Prosecutions of individuals are relatively rare, but the exposure applies to everyone under U.S. tax law.
Filing history also matters outside the tax system. Tax compliance is regularly cited as evidence of good moral character in applications for immigration relief, adjustment of status, and other benefits. A gap is harder to explain than a clean record, even when the dollar amounts are small.