Undocumented immigrants owe U.S. federal income tax on money earned in the country, and the IRS provides a way to file without a Social Security number. Taxes for undocumented immigrants work through an Individual Taxpayer Identification Number (ITIN), which lets you submit a return, pay what you owe, and claim a narrow set of credits. What has changed recently is not the obligation but the privacy environment around it, and that shift is worth understanding before you file.
How to File Without a Social Security Number
The IRS issues an ITIN to people who owe federal taxes but cannot get a Social Security number. It is a nine-digit number used strictly for tax processing. An ITIN does not authorize work, provide Social Security eligibility, or qualify you for the Earned Income Tax Credit.1Internal Revenue Service. Topic No 857 – Individual Taxpayer Identification Number ITIN
To apply, you complete IRS Form W-7 and submit it together with a federal tax return. The form asks for your legal name, mailing address, date of birth, and any tax ID number from your home country.2Internal Revenue Service. About Form W-7 – Application for IRS Individual Taxpayer Identification Number
Documents You Need
A valid, unexpired passport is the only document the IRS accepts on its own as proof of both identity and foreign status. Without a passport, you need at least two documents from the approved list, which includes a civil birth certificate, a national photo ID card, or a foreign voter registration card. For dependents under six, medical records may be used; for dependents under 24, school records are accepted. Every document must be an original or a certified copy from the issuing agency.3Internal Revenue Service. Instructions for Form W-7
Where to Send It
You can mail the W-7, tax return, and original documents to the IRS ITIN Operation in Austin, Texas.4Internal Revenue Service. How to Apply for an ITIN If mailing original passports and birth certificates makes you uneasy, two alternatives exist. Certain IRS Taxpayer Assistance Centers can authenticate most supporting documents in person and hand them back, though school and medical records for dependents still must be mailed.5Internal Revenue Service. IRS Taxpayer Assistance Centers With ITIN Services Certifying Acceptance Agents are IRS-authorized professionals who verify your originals, return them immediately, and mail certified copies with your application; fees typically run from $50 to several hundred dollars.6Internal Revenue Service. ITIN Acceptance Agents
Processing usually takes about seven weeks. During tax season (January 15 through April 30), plan on nine to eleven weeks. Applications from overseas can run longer. Once approved, the IRS mails a notice with your ITIN, which you use on every future return.
Keeping an ITIN Active
An ITIN expires if you do not use it on a federal tax return for three consecutive years. It lapses on December 31 following that third year of non-use.7Internal Revenue Service. How to Renew an ITIN Renewing uses the same Form W-7 and documents, and you can send a renewal on its own without attaching a return. Filing with an expired ITIN can delay any refund, so renewing ahead of tax season is worth doing.
What You Actually Owe
Federal income tax is the piece most people think about, but several other taxes come out of an undocumented worker’s earnings and spending.
Payroll Withholding
For W-2 employees, Social Security tax (6.2%) and Medicare tax (1.45%) are withheld from every paycheck, totaling 7.65%. The employer matches the same amount.8Internal Revenue Service. Topic No 751 – Social Security and Medicare Withholding Rates ITIN holders generally cannot collect Social Security retirement or disability benefits, so this money flows into a system they are unlikely to draw from. The Social Security portion applies to the first $184,500 in wages for 2026; Medicare has no cap.9Social Security Administration. Contribution and Benefit Base
Self-Employment Tax
If you work as an independent contractor, day laborer paid without withholding, or small business operator, you owe self-employment tax when your net profit passes $400 for the year.10Office of the Law Revision Counsel. 26 US Code 6017 – Self-Employment Tax Returns The rate is 15.3%, calculated on 92.35% of net earnings. That covers both the employee and employer sides of Social Security and Medicare, which is why the effective rate is higher than a W-2 worker’s.
Sales and Property Taxes
Sales tax applies at the register regardless of who is buying, with combined state and local rates averaging around 7.5% nationally and running past 10% in some places. Property taxes are built into rent because landlords pass those assessments through. Neither depends on immigration status.
Credits and Refunds an ITIN Filer Can Claim
ITIN filers can receive refunds on overpaid tax, but the major refundable credits sit behind a Social Security number requirement.
The Earned Income Tax Credit is off the table entirely. The statute requires a Social Security number for the filer and any qualifying children, and if one spouse on a joint return uses an ITIN, the whole return is disqualified.11Office of the Law Revision Counsel. 26 USC 32 – Earned Income
The Child Tax Credit is worth up to $2,200 per qualifying child for 2026, but it also requires an SSN for both the filer (or at least one spouse on a joint return) and the child. An ITIN does not satisfy the requirement.12Office of the Law Revision Counsel. 26 USC 24 – Child Tax Credit
What is available is the Credit for Other Dependents, worth up to $500 per dependent. It accepts dependents with an ITIN, SSN, or Adoption Taxpayer Identification Number, and it phases out starting at $200,000 of adjusted gross income ($400,000 on a joint return).13Internal Revenue Service. Child Tax Credit
In mixed-status families where one spouse has an SSN and the children have SSNs, the full Child Tax Credit is still available even if the other spouse files with an ITIN.
Penalties for Not Filing or Not Paying
The IRS charges two separate penalties, and they can stack. Failure to file costs 5% of the unpaid tax for each month or partial month the return is late, capped at 25%.14Internal Revenue Service. Failure to File Penalty Failure to pay costs 0.5% of the unpaid tax per month, also capped at 25%; that rate drops to 0.25% per month if you have an approved installment plan.15Internal Revenue Service. Failure to Pay Penalty Interest also accrues on the balance.
The filing penalty is ten times the paying penalty per month. If you cannot cover the full bill, file on time and pay what you can. That single choice avoids the bigger hit.
Privacy After the 2025 IRS–DHS Agreement
Federal law under 26 U.S.C. § 6103 makes tax returns and return information confidential and treats unauthorized disclosure by federal or state employees as a felony carrying up to five years in prison.16Office of the Law Revision Counsel. 26 USC 6103 – Confidentiality and Disclosure of Returns and Return Information For years, that statute functioned as a firewall between the IRS and immigration enforcement.
In 2025, the Treasury Department and the Department of Homeland Security signed a memorandum of understanding allowing Immigration and Customs Enforcement to submit names and addresses to the IRS for cross-verification against tax records. The U.S. Court of Appeals for the D.C. Circuit declined to block the arrangement, finding that the information being shared was not covered by Section 6103’s restrictions on return information. The scope and implementation remain the subject of ongoing litigation as of 2026.
The older assurance that the IRS would never share information with immigration authorities no longer describes the current environment. Anyone filing should weigh this before submitting a return and, where possible, consult an immigration attorney or a tax professional familiar with the current enforcement posture.
State tax agencies follow their own privacy rules. Some states have laws that specifically bar their revenue departments from sharing taxpayer data with federal immigration authorities; others do not. If that protection matters to your decision, check your state revenue department’s current policy or ask a local professional.
Why Some People Still File
A consistent tax filing history can matter later. In immigration court, judges evaluating applications for cancellation of removal look at whether the applicant has shown “good moral character” over time, and years of filed returns serve as concrete evidence of financial responsibility and community ties.
That creates a real tension. Filing builds a record that may help in a future legal proceeding, and it also puts personal information into a federal system whose privacy protections have narrowed. There is no single right answer. The decision turns on your specific circumstances, your risk tolerance, and the legal situation you may face down the road, and an immigration attorney is the right person to help you weigh it.