If you've just hired your first employee, you've probably run into both forms in the same week, and it's easy to assume they're two halves of the same task. They're not. Here's what each one actually does.
This is educational content, not legal or tax advice — for your specific hiring situation, talk to an employment attorney or your payroll provider.
The short version
Form I-9 (Employment Eligibility Verification) confirms that the person you hired is legally authorized to work in the United States. You complete it at hiring, you keep it in your files, and you do not send it to any government agency unless it's requested in an audit.
Form W-2 (Wage and Tax Statement) reports the wages you paid an employee and the taxes you withheld over the calendar year. You file it with the Social Security Administration and give a copy to the employee every January.
So: the I-9 happens once, at the start, and stays with you. The W-2 happens every year, at the end, and goes out to the government and the worker.
Form I-9 — verifying who can work
Every employer must complete an I-9 for every employee hired to work in the U.S., regardless of citizenship. It has two sides:
- Section 1 — the employee completes this no later than their first day of work, attesting to their work-authorization status.
- Section 2 — you (the employer) complete this within three business days of the start date, after examining documents that prove identity and work authorization (for example, a passport, or a driver's license plus a Social Security card).
You keep the completed I-9 on file — separately from the regular personnel file is the common best practice — for as long as the person works for you, plus a retention window after they leave (the later of three years from hire or one year from termination).
You never mail the I-9 anywhere. It lives in your records. The penalty exposure comes from not having one, having an incomplete one, or not being able to produce it if Immigration and Customs Enforcement requests an inspection.
Form W-2 — reporting what you paid
The W-2 is a year-end document. After running payroll all year, you report each employee's total wages, plus the federal income tax, Social Security, and Medicare you withheld, plus any state withholding. The deadline is January 31 for both copies:
- The employee's copy, so they can file their personal return.
- The Social Security Administration's copy (filed along with Form W-3, the transmittal summary).
If you run payroll through a provider, the W-2s are usually generated for you — but the numbers are only as good as the bookkeeping behind them. Misclassified pay, untracked reimbursements, or messy payroll records show up as wrong W-2s, which means amended forms and annoyed employees.
Where the confusion comes from
Both forms appear at the edges of the employment relationship, both have a number-letter name, and both involve the employee's identity and Social Security number. But they answer different questions:
- I-9 asks: "Is this person allowed to work here?" (Once, at hire.)
- W-2 asks: "What did this person earn and what did we withhold?" (Every year, at year-end.)
And neither is the same as the W-4, which the employee fills out so you know how much income tax to withhold, or the 1099-NEC, which goes to independent contractors rather than employees. If you're deciding whether a worker is even an employee in the first place, that's a different question — see our guide on 1099 vs. W-2 classification.
The hiring-paperwork checklist for a new W-2 employee
When you bring on an actual employee (not a contractor), the usual starting stack is:
- Form I-9 — work authorization, kept on file.
- Form W-4 — federal withholding elections (plus any state equivalent).
- Direct deposit / banking details for payroll.
- State new-hire reporting — most states require reporting a new hire within a set number of days.
- Workers' comp coverage in place before they start.
- And at year-end, the W-2 that summarizes it all.
Bringing on a contractor instead? The contractor stack is much shorter — a W-9 and a possible 1099-NEC — which is exactly why classification matters.
Common mistakes
- Skipping the I-9 entirely because nobody asked for it — it's required even if no one ever audits you.
- Completing Section 2 late (after the three-business-day window).
- Over-documenting — demanding specific documents or more than the form requires can itself be a violation.
- Treating a 1099 contractor like an employee and never realizing you skipped the whole employee paperwork chain.
- Wrong W-2 numbers because payroll and bookkeeping never reconciled during the year.
Frequently asked questions
No. The I-9 stays in your records. You only produce it if a federal agency such as ICE requests an inspection. The W-2, by contrast, is filed with the Social Security Administration every year.
Every U.S. employee needs an I-9 completed at hire. They'll also receive a W-2 after any year in which you paid them wages. Independent contractors get neither — they complete a W-9 and may receive a 1099-NEC.
The W-4 is filled out by the employee at hiring so you know how much income tax to withhold. The W-2 is produced by you at year-end to report what was actually paid and withheld. The W-4 is an input; the W-2 is the output.
Keep it for as long as the person is employed, then for the later of three years after the hire date or one year after employment ends. Many employers store I-9s separately from the main personnel file.
Book a free consultation or learn more about our bookkeeping services.
This post is educational content, not legal or tax advice. For your specific situation, consult a qualified attorney or CPA.