What goes on each line of the W-4

The W-4 has six main sections, and most people only need to complete three of them. Start with your name, address, and Social Security number at the top — this is how your employer and the IRS match the form to your tax records. Then move to the filing status box: check the box that matches your situation (single, married filing jointly, married filing separately, or head of household). This determines how much tax your employer withholds from each paycheck.

Lines 2 through 6 are where the actual withholding calculation happens. Line 2 asks if you have more than one job or if your spouse works — if yes, you'll need to do extra math or use the IRS worksheet. Line 3 is for claiming dependents (children and other relatives you support). Line 4 is for other income that isn't from a job, like interest or rental money. Line 5 is for deductions you plan to claim when you file your tax return. Line 6 is for any extra tax you want withheld each paycheck.

Key Takeaways

  • Fill in your name, address, and Social Security number at the top, then select your filing status — this information is required on every W-4.
  • If you have only one job and no spouse working, you can skip lines 2 through 5 and just sign and date the form.
  • If you have multiple jobs or a working spouse, use the IRS worksheet on the back of the form or go to irs.gov/w4app to calculate the right withholding.
  • You can request extra tax withheld on line 6 if you expect to owe money at tax time, or leave it blank if your withholding is already correct.
  • Submit the completed form to your employer's payroll department — keep a copy for your records.

Step-by-step for a single job with no dependents

If you work one job, have no dependents, and your spouse doesn't work (or you're not married), the W-4 is straightforward. Write your full name on line 1(a), your middle initial on line 1(b), and your last name on line 1(c). Put your home address on line 1(d) and your city, state, and ZIP code on line 1(e). Enter your Social Security number on line 1(f).

On line 2, check the box for your filing status — most single people check "Single". Leave lines 2 through 5 blank. Sign and date the form on line 7, and you're done. Hand it to your payroll department or upload it to your employer's HR system if they have one.

When you need to use the worksheet

The IRS worksheet on the back of the W-4 is required if you have two or more jobs, if you're married and both you and your spouse work, or if you have significant non-job income. The worksheet walks you through calculating a number that goes on line 2(c), which tells your employer how much to withhold. It takes about five minutes if you have your pay stubs and last year's tax return handy.

Alternatively, you can use the IRS W-4 calculator at irs.gov/w4app — it's an online tool that asks you questions about your income and life situation, then tells you exactly what to enter on each line. Many people find this faster and less error-prone than doing the math by hand. Either method produces the same result.

Claiming dependents on line 3

Line 3 is where you enter the number of dependents you claim on your tax return. A dependent is usually a child under 17, a college student you support, or another relative living with you that you pay for. For each dependent, you reduce the amount of tax your employer withholds — this puts more money in your paycheck now instead of getting it back as a refund later.

Only count dependents you actually claim on your tax return. If you're not sure whether someone qualifies, check the IRS website or talk to a tax preparer before filling out the W-4. Claiming dependents you don't actually have will result in underpaying taxes and owing money when you file.

Requesting extra withholding on line 6

Line 6 is optional and is used only if you want your employer to take out more tax than the standard calculation requires. This makes sense if you have side income that doesn't have taxes withheld, if you're self-employed, or if you know from past years that you always owe money at tax time. You can request a flat dollar amount per paycheck — for example, $50 extra per week.

To figure out how much extra to request, look at your last tax return and see how much you owed. Divide that by the number of paychecks you'll receive this year, and enter that amount on line 6. This spreads the payment across the year instead of paying it all at once when you file.

What to do after you complete it

Once you've filled out and signed the W-4, give it to your payroll department or HR office. Some employers accept it in person, some want it emailed, and some have an online portal where you upload it. Ask your employer how they prefer to receive it. Keep a copy for yourself — you'll want it if there's ever a question about your withholding.

Your new withholding takes effect on your next paycheck, usually within one or two pay periods. If you notice your paycheck changed and it doesn't match what you expected, contact payroll to make sure the form was entered correctly. You can submit a new W-4 at any time if your situation changes — getting married, having a child, taking a second job, or losing a job all warrant a new form.

Common mistakes to avoid

The most common error is leaving line 1(f) blank — your Social Security number is required, and without it your employer can't process the form. Another frequent mistake is checking the wrong filing status. If you're married but check "Single," your withholding will be wrong for both you and your spouse. Take a moment to confirm you've selected the status that matches your actual situation on December 31 of the tax year.

People also sometimes claim more dependents than they actually have, thinking it will give them a bigger refund. It won't — it just means you'll owe taxes when you file. And if you have multiple jobs, skipping the worksheet and leaving lines 2 through 5 blank will almost certainly result in underpaying. Use the worksheet or the online calculator if you have more than one income source.

Frequently Asked Questions

Do I have to fill out a W-4 every year?

No. Your W-4 stays in effect until you submit a new one. You only need to fill out a new form if your situation changes — you get married, have a child, get a second job, or your income changes significantly. Some employers ask you to review your W-4 annually, but you don't have to change it unless you want to.

What if I don't want any tax withheld?

You can claim exemption from withholding on line 4(c) only if you had no tax liability last year and expect none this year. This is rare and usually applies only to students or people with very low income. If you claim exemption incorrectly, you'll owe taxes when you file and may face penalties. Talk to a tax preparer if you think this applies to you.

Can I change my W-4 after I submit it?

Yes. You can submit a new W-4 to your employer at any time. Your new withholding will start on the next paycheck. There's no penalty for changing it, and you can change it as many times as you need to.

What if my employer won't accept my W-4?

Your employer is required to accept a valid W-4. If they refuse, contact your state's labor department or the IRS. Make sure your form is complete and signed — incomplete forms can be rejected. If you've submitted a complete, signed form and your employer still refuses, that's a violation of federal law.

Do I need to file a W-4 if I'm self-employed?

No. Self-employed people don't use a W-4 because there's no employer to withhold taxes. Instead, you pay estimated taxes quarterly using Form 1040-ES. Talk to a tax preparer or visit irs.gov for guidance on self-employment tax.