Form W-4 tells your employer how much federal income tax to withhold from your paycheck. The version in use has no "allowances" — the IRS redesigned it around five plain-language steps. Most people only need Step 1 (your details) and Step 5 (sign). Steps 2 through 4 add accuracy when you have more than one job, a working spouse, or dependents — skipping them then causes a surprise bill.
What Form W-4 Is
Form W-4, "Employee's Withholding Certificate," is new-hire paperwork you give to your employer, not the IRS. It sets your withholding — the amount taken out of each paycheck toward your income tax. Get it roughly right and your year-end return is close to zero; get it wrong and you either overpay all year or owe a lump sum in April.
The Five Steps
- Step 1 — Personal information. Name, address, Social Security number, and filing status. Required for everyone.
- Step 2 — Multiple jobs. Complete this if you hold more than one job or you're married filing jointly and your spouse also works. This is the step people skip that most often leads to under-withholding.
- Step 3 — Dependents. Claim the child tax credit and credit for other dependents here if your income is under the threshold.
- Step 4 — Other adjustments. Optional: other income not from jobs, deductions beyond the standard deduction, or extra withholding per paycheck.
- Step 5 — Sign. The form isn't valid until you sign and date it.
Why doesn't Form W-4 use allowances anymore?
The IRS removed withholding "allowances" in the 2020 redesign because they were tied to personal exemptions that the 2017 tax law suspended. The current form asks about your actual situation — jobs, dependents, other income — instead of a number of allowances, which makes it more accurate but unfamiliar if you last filled one out years ago. If your only reference is an old W-4, ignore the allowances muscle memory and follow the five steps.
Is the W-4 the same as Form I-9?
No — they're both day-one hire paperwork but answer different questions. The I-9 proves you're authorized to work; the W-4 sets your tax withholding. You typically complete both when you start a job, and both reuse your name, address, and SSN — the repeated identity block an AI form filler holds once so you don't retype it per form.
When should I update my W-4?
Whenever a life change shifts your tax picture: marriage or divorce, a new baby, a second job, a spouse starting or stopping work, or a large refund or bill last year. You can submit a new W-4 to your employer any time — you're not locked into the one you signed at hire.