TL;DR
- ✅ W-4: you fill it out at the start, telling your employer how much to withhold
- ✅ W-2: your employer sends it by January 31, reporting what was earned and withheld
- ✅ The W-4 you choose changes the numbers on the W-2
- ✅ Use last year’s W-2 to decide whether to change your W-4
How the two forms connect
1. You submit a W-4
At hire, or any time your situation changes. It stays in effect until you replace it.
2. Your employer withholds
Each paycheck, using your W-4 and the IRS tables.
3. Your employer issues a W-2
By January 31, totaling your wages and the tax withheld.
4. You file your return
Your W-2 numbers are your payments toward your tax. A refund or bill is the difference.
The W-2 boxes that matter for your W-4
- Box 1: taxable wages. It is lower than gross pay if you contribute to a 401(k) or health plan.
- Box 2: federal income tax withheld. This is the number your W-4 controls.
- Boxes 3–6: Social Security and Medicare wages and tax. A W-4 does not change these.
- Boxes 15–17: state wages and tax withheld, controlled by your state withholding form.
Use your numbers to update your W-4 — free
Enter your pay and what you owed or got back to see what to change.
Open the W-4 Calculator →Using the W-2 to fix next year’s W-4
If you owed on your last return, compare Box 2 with your total tax. The shortfall divided by the paychecks in a year is the extra amount to put in Step 4(c); see the Step 4(c) guide and how to stop owing taxes. If you received a large refund, you can reduce withholding; see refund vs. adjusting your W-4.
⚠️ Not an employee?
Contractors fill out a W-9 and receive a 1099 instead of a W-2. See W-4 vs. W-9.
Frequently asked questions
What is the difference between a W-4 and a W-2?
A W-4 is a form you give your employer to set how much federal income tax is withheld. A W-2 is a form your employer gives you after the year ends, reporting what you earned and what was withheld, which you use to file your return.
Which comes first, the W-4 or W-2?
The W-4 comes first, when you start the job. The W-2 follows in January. Your W-4 choices decide the numbers on your W-2.
When do I get my W-2?
Employers must send W-2s by January 31 for the previous year. If you have not received yours by mid-February, contact your employer, then the IRS.
Which box on the W-2 shows federal withholding?
Box 2 shows federal income tax withheld and Box 1 shows taxable wages. Boxes 4 and 6 show Social Security and Medicare tax withheld, which your W-4 does not affect.
Can I use my W-2 to fix my W-4?
Yes. Compare Box 2 with the tax on your return. If you owed, increase withholding; if you got a large refund, you can reduce it. A final pay stub from December has the same year-to-date data earlier.
Key terms in this article
Related guides
W-4 vs. W-9: What’s the Difference and Which Do You Fill Out?
W-4 is for employees, W-9 for contractors. What each does and how taxes differ.
How to Stop Owing Taxes at Tax Time: Fix Your W-4 (2026)
Owe the IRS every April? Why withholding falls short and which W-4 lines close the gap on your next paycheck.
How to Fill Out a W-4 for a New Job (2026 Step-by-Step)
Starting a new job and staring at a blank W-4? This guide walks you through all 5 steps — including what to do if you have a second job or your spouse works.
Tax Refund vs. Adjusting Your W-4: How to Keep More Money Every Paycheck
The average refund is $3,100 — that's money that was yours all year. Here's how to decide whether a big refund is working for you or against you.
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