W-2 vs. W-4 at a glance
| Form W-4 | Form W-2 | |
|---|---|---|
| Who fills it out | You, the employee | Your employer |
| When | At hire, or anytime withholding needs change | Once a year, by January 31 |
| Purpose | Sets how much tax is withheld from each paycheck | Reports total wages and taxes withheld for the year |
| Filed with the IRS? | No—kept by your employer | Yes—filed with the Social Security Administration |
What Form W-4 does
Form W-4 tells your employer how much federal income tax to take out of each paycheck. You fill it out when you start a job, listing your:
- Filing status
- Dependents
- Any other income that affects withholding
Your employer keeps the form on file rather than sending it to the IRS.
What Form W-2 does
Form W-2 is the form your employer prepares at year-end. It reports your total taxable wages along with taxes withheld, such as:
- Federal taxes
- Social Security taxes
- Medicare taxes
Your employer files your W-2 with the Social Security Administration and sends you a copy to use when you file your return.
How your W-4 choices show up on your W-2
The filing status, dependents, and extra withholding you enter on your W-4 determine how much tax your employer takes out all year, which becomes the Box 2 federal withholding figure on your W-2. Claim too few adjustments, and you could receive a bigger refund; claim too many, and you might owe at tax time.
When to update your W-4
Update your W-4 any time your situation changes, whether you’re:
- Getting married or divorced
- Having a child
- Picking up a second job or your spouse is starting work
The IRS recommends updating promptly for any of these, so your withholding stays accurate.
Note: If a life event decreases the withholding you’re entitled to claim (e.g., divorce, or no longer qualifying for exempt status), federal regulations actually require you to submit a new W-4 within 10 days of the change—for other life events (like marriage or a new child), updating is strongly advised but not a strict legal deadline.
