The short answer: a U.S. employer may legally hire any person who is authorized to work in the United States, regardless of citizenship or national origin. Knowingly hiring a worker who is not authorized to work is illegal under federal law, and an Individual Taxpayer Identification Number (ITIN) is not proof of work authorization. To hire foreign nationals lawfully, you generally need them to already hold work authorization or to sponsor them through a work visa.
This is general information to help you understand the compliance landscape, not legal advice. Immigration and employment law is technical, the penalties are steep, and the right move in a specific situation usually calls for qualified counsel.
The Federal Baseline: IRCA and the I-9
The governing law here is the Immigration Reform and Control Act of 1986 (IRCA), which amended the Immigration and Nationality Act (INA). IRCA makes it unlawful for an employer to knowingly hire, recruit, or refer for a fee any person who is not authorized to work in the United States. It is enforced primarily by U.S. Immigration and Customs Enforcement (ICE), part of the Department of Homeland Security (DHS), through worksite enforcement and audits of the U.S. Citizenship and Immigration Services (USCIS).
IRCA requires every U.S. employer to verify the identity and employment authorization of every new hire using Form I-9, Employment Eligibility Verification. This applies to citizens and noncitizens alike. You cannot decide to run the I-9 only on workers who "look" or "sound" foreign; doing so is itself illegal discrimination.
Key I-9 mechanics that employers get wrong:
- Timing. The employee completes Section 1 no later than their first day of work for pay. The employer completes Section 2 within three business days of the start date.
- Document choice belongs to the employee. The worker chooses which document(s) to present from the Form I-9 Lists of Acceptable Documents (List A, or a combination of List B and List C). You may not demand a specific document, demand more documents than required, or reject documents that reasonably appear genuine. This is called "document abuse" and is prohibited.
- Reverification. If a worker's employment authorization has an expiration date, you reverify before it lapses. You do not reverify U.S. passports, Permanent Resident Cards (green cards), or List B identity documents.
- Retention. Keep the I-9 for the later of three years after hire or one year after employment ends.
Can an Employer Hire an Undocumented Immigrant?
No. Knowingly hiring or continuing to employ a worker you know is not authorized to work violates IRCA. "Knowingly" includes constructive knowledge - situations where the facts would lead a reasonable person to conclude the worker lacks authorization but the employer ignores them. Penalties escalate with each violation and can include civil fines per worker, debarment from federal contracts, and, for a pattern or practice of knowing violations, criminal prosecution.
At the same time, you cannot swing to the opposite extreme. The Immigrant and Employee Rights Section (IER) of the U.S. Department of Justice enforces the INA's anti-discrimination provisions, which bar citizenship-status and national-origin discrimination in hiring, firing, and the I-9 process. Refusing to hire someone solely because they are not a U.S. citizen - when they are in fact authorized to work - can expose you to liability. Lawful permanent residents, asylees, refugees, and many visa holders are fully authorized to work.
The practical takeaway: complete the I-9 honestly and uniformly for everyone, accept facially valid documents, and do not play immigration agent. You are verifying authorization, not investigating immigration status.
Can an Employer Hire Someone With an ITIN?
An ITIN is a tax-processing number issued by the IRS to people who must file U.S. taxes but are not eligible for a Social Security Number. It exists so that income gets reported and taxed. An ITIN is not work authorization, and it is not an acceptable document for completing the I-9.
This trips up employers because the two questions feel related but are governed by different agencies:
- Work authorization is verified through the I-9 (DHS/USCIS) - the worker must present documents establishing identity and authorization to work.
- Tax reporting is handled through the IRS. For payroll, an authorized employee normally provides a Social Security Number on Form W-4 so wages can be reported on a W-2.
An ITIN is generally used for non-wage situations (for example, certain self-employed independent contractors, or spouses and dependents filing taxes) - not as a substitute for an SSN on payroll for an employee. If a person is genuinely an independent contractor (not an employee), the I-9 requirement does not apply, but you must be sure the classification is correct; misclassifying employees as contractors carries its own wage-and-hour and tax liability. Bottom line: do not treat an ITIN as a green light to put someone on payroll as an employee. Authorization must still be established on the I-9.
Can My Company Hire Foreign Workers?
Yes - many foreign nationals are eligible to work in the U.S., either because they already hold work authorization or because an employer sponsors them. There are two broad paths.
Workers who are already authorized
Some foreign nationals can work for any employer without sponsorship. These include lawful permanent residents, asylees and refugees, certain spouses of visa holders, and individuals holding an Employment Authorization Document (EAD, Form I-766). You hire them like anyone else: complete the I-9 and accept their valid documents.
Workers who need employer sponsorship
Other foreign nationals need you to petition for a specific work visa tied to your company. Common categories include:
- H-1B - specialty occupations generally requiring at least a bachelor's degree. Subject to an annual numerical cap and a lottery, with statutory exemptions for some employers.
- H-2A and H-2B - temporary or seasonal agricultural (H-2A) and non-agricultural (H-2B) labor.
- L-1 - intracompany transferees moving from a related foreign entity.
- O-1 - individuals with extraordinary ability.
- TN - certain Canadian and Mexican professionals under the USMCA (formerly NAFTA).
- Employment-based green cards (PERM) - the path to permanent residence, which for many categories requires a labor certification.
Sponsorship typically involves the U.S. Department of Labor (for example, a Labor Condition Application for H-1B or a labor certification for many green cards), then a petition to USCIS (often Form I-129 for nonimmigrant workers), and finally consular processing or a change of status. Several of these programs require you to pay prevailing wages and meet specific recruitment or working-condition obligations. The rules are detailed and the timelines and caps shift, so most employers work with immigration counsel for sponsorship.
E-Verify: Required in Some Places, Optional in Others
E-Verify is a free DHS/USCIS online system that compares I-9 information against government records. It does not replace the I-9 - you still complete the I-9 first. E-Verify is voluntary under federal law for most private employers, but it is mandatory for many federal contractors and is required by law in a number of states. Whether you must enroll, and for which employees, varies by state and by contract, so confirm your specific obligations before deciding. You may not use E-Verify selectively or to pre-screen applicants before hire.
Don't Forget the Other Federal Employment Laws
Work authorization is only one layer. Once someone is your employee, the full sweep of federal employment law applies regardless of immigration status. The Fair Labor Standards Act (FLSA), enforced by the U.S. Department of Labor Wage and Hour Division, requires minimum wage and overtime even for undocumented workers. Title VII of the Civil Rights Act, the ADA, and the ADEA, enforced by the EEOC, bar discrimination, including national-origin discrimination. OSHA protects worker safety. Many states layer on stronger protections - higher minimum wages, broader anti-discrimination coverage, and additional sick-leave or notice requirements - and this varies by state.
Practical Compliance Steps for Employers
- Run the I-9 on every hire, uniformly. Use the current version of the form and follow the timing rules (Section 1 by day one, Section 2 within three business days).
- Let the employee pick their documents. Accept anything that reasonably appears genuine and relates to the person; never demand specific or extra documents.
- Build a tickler system for reverification of expiring work authorization, and a retention schedule (three years after hire or one year after termination, whichever is later).
- Decide on E-Verify based on your state and contracts, and apply it consistently if you enroll.
- Separate tax questions from authorization questions. An ITIN handles tax filing; it never establishes the right to work as an employee.
- For sponsorship, start early and get counsel. Caps, prevailing-wage rules, and processing times make these programs unforgiving of mistakes.
- Document your process, not your assumptions. Self-audit your I-9s periodically, correct errors transparently (line through, initial, date - never backdate), and train whoever handles onboarding.
If you are facing an ICE Notice of Inspection, considering sponsoring a worker, unsure whether someone's documents are acceptable, or worried about a possible discrimination or document-abuse claim, that is the moment to talk to an employment and immigration compliance attorney. The cost of qualified advice is small next to per-worker penalties and the disruption of a worksite audit.
The law behind your rights at work
Background checks are governed by the federal Fair Credit Reporting Act, plus anti-discrimination law and state ban-the-box rules.
Key federal laws:
Where to get help or file a complaint:
Your state and city matter. Federal law is the floor — many states and cities require higher pay, more leave, and broader protections. Always check your state’s rules (and any local ordinances) in addition to the federal laws above. This is general legal information, not legal advice.
Frequently asked questions
Can an employer hire an illegal immigrant?
No. Under the Immigration Reform and Control Act, it is unlawful to knowingly hire or continue to employ someone who is not authorized to work in the U.S., and that includes situations where the facts clearly suggest the worker lacks authorization. Every new hire must complete Form I-9. At the same time, you cannot refuse to hire someone simply because they are not a U.S. citizen if they are in fact authorized to work, because that can be illegal citizenship-status discrimination.
Can an employer hire someone with an ITIN?
An ITIN is an IRS tax-processing number, not work authorization, and it is not an acceptable Form I-9 document. You cannot rely on an ITIN to put someone on payroll as an authorized employee. ITINs are used for tax filing by people ineligible for a Social Security Number, including some independent contractors and tax dependents. Work authorization must still be established on the I-9 with valid documents.
Can my company hire foreign workers?
Yes. Many foreign nationals are already authorized to work, such as lawful permanent residents, asylees, refugees, and EAD holders, and you hire them like anyone else by completing the I-9. Others need employer sponsorship through a work visa such as H-1B, H-2A/H-2B, L-1, O-1, or TN, which usually involves the Department of Labor and USCIS. Sponsorship has caps, prevailing-wage rules, and deadlines, so most employers use immigration counsel.
Is E-Verify required for my business?
It depends. E-Verify is voluntary under federal law for most private employers but is mandatory for many federal contractors and is required by law in a number of states. It supplements the I-9; it does not replace it, and you cannot use it to pre-screen applicants before hiring. Check your state's rules and any federal contract clauses to confirm your obligations, because this varies by state.
Do federal wage and discrimination laws apply to undocumented workers?
Yes. Once someone is working for you, laws like the Fair Labor Standards Act (minimum wage and overtime, enforced by the U.S. Department of Labor Wage and Hour Division) and Title VII, the ADA, and the ADEA (anti-discrimination, enforced by the EEOC) generally apply regardless of immigration status. OSHA safety protections apply too, and many states add stronger protections.
This article is general legal information, not legal advice, and may not reflect the most current law or the law in your jurisdiction. Laws vary by state and change over time. For advice about your specific situation, consult a licensed attorney.
