Form I-9 is one page of boxes and checkmarks, which is exactly why it is easy to underestimate. Every US employer, regardless of size, must complete it for every new employee hired, including US citizens. Missed deadlines, missing signatures and over-documentation are among the most common findings in government audits, and penalties are assessed per form.
This guide covers the essentials: who needs a Form I-9, the deadlines for each section, acceptable documents, remote verification, reverification and how long to keep the forms.
Who needs to complete Form I-9
You must complete Form I-9 for every person you hire to perform work in the United States in exchange for wages or other compensation. That includes full-time, part-time, seasonal and temporary employees, and US citizens. You do not complete a Form I-9 for genuine independent contractors, though you cannot use a contractor arrangement to knowingly avoid the requirement.
Always use the current edition of the form from the USCIS website. Using an outdated edition is a technical violation.
Deadlines: Section 1 and Section 2
| Step | Who completes it | Deadline |
|---|---|---|
| Section 1: Employee information and attestation | Employee | No later than the first day of employment (they may complete it after accepting the offer) |
| Section 2: Employer review of documents | Employer or authorized representative | Within 3 business days of the employee's first day of work |
| Short-term hires (less than 3 business days) | Employee and employer | Both sections by the end of the first day of work |
| Supplement B (reverification and rehires) | Employer | No later than the date work authorization expires, for documents that require reverification |
For example, if an employee starts work on a Monday, Section 2 must be completed by Thursday. Do not complete the form before the person has accepted the job offer.
Acceptable documents
The employee chooses which acceptable documents to present. They may present either one document from List A, or one document from List B and one from List C.
List A: identity and work authorization
- US passport or US passport card
- Permanent Resident Card (Form I-551)
- Employment Authorization Document with photo (Form I-766)
- Certain foreign passports with Form I-94 or an I-551 stamp or notation
List B: identity only
- Driver's license or state ID card with a photo or identifying information
- School ID with a photo
- Voter registration card
- US military card or draft record
List C: employment authorization only
- Social Security card without employment restrictions
- Certified US birth certificate
- Certain DHS-issued employment authorization documents
The full lists, including acceptable receipts, appear in the form instructions. Documents must be unexpired and must reasonably appear genuine and relate to the person presenting them.
Do not over-document
You cannot tell employees which documents to provide, ask for more documents than required, or reject valid documents because of a future expiration date. Asking a non-citizen for a specific document such as a green card, while letting citizens choose freely, can be unlawful discrimination under the immigration law's anti-discrimination provisions. Your offer letter and onboarding materials should simply say the employee must provide acceptable documents from the lists.
Remote document review
Traditionally, the employer must physically examine original documents in the employee's presence. Employers enrolled in E-Verify and in good standing may instead use the DHS-authorized alternative procedure: examine copies of the documents, then conduct a live video interaction with the employee showing the same documents, check the box on the form and keep copies. If you offer the alternative procedure at a hiring site, apply it consistently.
Employers not using E-Verify can designate an authorized representative, such as a notary or trusted contact, to examine documents in person on the employer's behalf. The employer remains responsible for any errors the representative makes.
E-Verify
E-Verify is a federal online system that compares I-9 information against government records. It is voluntary for most private employers under federal law, but some states require some or all employers to use it, and federal contractors may be required to use it. Check the rules in your state through our state HR law guides.
Reverification, rehires and name changes
Some employees present documents showing temporary work authorization, such as an Employment Authorization Document with an expiration date. Before that date, the employee must present a document showing continued authorization, and you record it in Supplement B. Do not reverify US citizens, noncitizen nationals or lawful permanent residents who presented a Permanent Resident Card, and never reverify List B identity documents.
If you rehire a former employee within three years of the date their original Form I-9 was completed, you may update Supplement B rather than completing a new form, as long as their earlier documents still show work authorization. You can also simply complete a new form. When a current employee changes their name, you may record the change in Supplement B, but you are not required to.
How long to keep Form I-9
Keep each Form I-9 for as long as the person works for you. After employment ends, keep it for 3 years after the date of hire or 1 year after the date employment ended, whichever is later.
- Store I-9s separately from personnel files, so that an inspection does not expose unrelated records.
- If you photocopy documents, do it for everyone, not selectively, and store copies with the form.
- Electronic storage is permitted if the system meets federal requirements for integrity, security and retrieval.
- Purge forms on schedule once the retention period has passed.
Form I-9 checklist
- Use the current edition of the form.
- Have the employee complete Section 1 no later than day one.
- Review the documents the employee chooses and complete Section 2 within 3 business days.
- Do not request specific documents or extra documents.
- Record document titles, numbers and expiration dates accurately.
- Sign and date as the employer or authorized representative.
- Calendar reverification dates for temporary work authorization.
- Store forms separately and securely.
- Calculate and track each form's retention date.
- Run an internal audit periodically and correct errors properly.
Fixing mistakes
If you find an error, correct it by drawing a line through the incorrect information, entering the correct information, and initialing and dating the change. Do not use correction fluid or backdate. If Section 2 was never completed, complete it now with the current date and attach a short, signed explanation. Only the employee should correct Section 1.
Key takeaways
- Every employer must complete Form I-9 for every new hire, including US citizens.
- Section 1 is due by the first day of work; Section 2 within 3 business days.
- The employee chooses the documents; never ask for specific or extra documents.
- Keep forms for 3 years after hire or 1 year after termination, whichever is later.
- Regular self-audits catch errors before an inspection does.
Build I-9 into onboarding
AskHrAI's onboarding tool helps you build a checklist so the I-9, tax forms and policy acknowledgments happen on time for every hire.
This article is general information, not legal advice. Employment laws change and vary by state and city — confirm details with your state labor department or an employment attorney.