How to fill out a W-4

The form has five steps. Only Step 1 and Step 5, your details and your signature, are required. Everything in between is an adjustment, and each one moves withholding in a known direction: Step 2 and Step 4(a) raise it, Step 3 and Step 4(b) lower it, and Step 4(c) adds a fixed amount. Payroll software runs the result through the percentage method in IRS Publication 15-T every pay period, which is the same method our calculators use. The figures below come from that method for the 2026 tax year.

Step 1: filing status is the biggest lever

Your filing status picks the withholding table and the standard deduction built into it. For 2026 the standard deduction is $16,100 for single filers, $24,150 for head of household and $32,200 for married couples filing jointly. Payroll assumes you will take that deduction, so the first slice of your pay is withheld at nothing.

If you are single with one job and nothing else, Step 1 and Step 5 are all you need. On a $60,000 salary paid every two weeks, federal withholding comes to $193.08 a paycheck, or $5,020 over the year. The tax on that income works out to $5,020. The tables are built to land close to the real bill for this simple case, and they do.

Head of household is only for unmarried people who pay more than half the cost of a home for a qualifying person, usually a child. Picking it without qualifying lowers your withholding, and the shortfall arrives as a bill when the return is filed.

Step 2: two jobs, or a working spouse

This is where most under-withholding starts. Each employer withholds as if its paycheck were the household’s only income, so each one hands you the full standard deduction and the low brackets. Add the two jobs together on the return and the second job’s income lands in higher brackets than either employer assumed.

Take a married couple earning $70,000 and $50,000, both paid every two weeks, both filing the form as married with nothing else filled in. The first job withholds $155.38 a paycheck and the second $68.46, which adds up to $5,820 over the year. Their actual federal income tax on $120,000 of wages is $10,040. They are $4,220 short, and nothing on their pay stubs warns them.

Step 2 offers three fixes:

• The checkbox in Step 2(c). Both spouses check it. Each employer then uses a table that assumes half the household’s deductions and brackets. For the couple above, withholding rises to $252.69 and $146.92 a paycheck, $10,390 a year, which is $350 more than the tax owed. The checkbox works best when the two incomes are similar.
• The Multiple Jobs Worksheet. It gives a dollar figure for Step 4(c) on the higher-paying job only. It is more precise when the incomes are far apart, but it has to be redone whenever either salary changes.
• The IRS Tax Withholding Estimator, or our W-4 helper, which does the same arithmetic with your actual pay.

Pick one method, not two. Checking the box and also adding the worksheet amount withholds roughly twice the correction.

Step 3: children and other dependents

Step 3 converts tax credits into lower withholding. You enter $2,200 for each child under 17 and $500 for each other dependent, such as a college student or a parent you support, and payroll spreads that total across the year’s paychecks.

Consider a married earner on $90,000 with two children, the only income in the household. Without Step 3 the paycheck withholds $247.69. Entering $4,400 in Step 3 drops that to $78.46, which is $169.23 more take-home pay every two weeks. Over the year that withholds $2,040, the same as the household’s tax of $2,040 after the child tax credit.

The credit phases out at higher incomes, and the form’s instructions limit Step 3 to households under the income ceiling printed on the form. If both spouses work, claim the children on one W-4 only, normally the higher-paying job. Claiming them on both halves the withholding twice for the same credit.

Step 4(a): other income without withholding

Interest, dividends, a small rental or retirement income all add to your tax without any withholding of their own. Step 4(a) lets you report an estimate of that income so payroll withholds on it as if it were extra salary. Self-employment income can go here too, though Step 4(a) does not cover self-employment tax. For freelance income of any size, quarterly estimated payments or a Step 4(c) amount usually fit better.

Our single earner on $60,000 with $8,000 of side income would owe about $1,110 at tax time if the W-4 stayed as it was. Entering the side income in Step 4(a) raises withholding from $193.08 to $235.77 a paycheck. The W-4 helper reaches a similar result a different way: $43 of extra withholding per paycheck in Step 4(c).

Step 4(b): deductions above the standard deduction

Use Step 4(b) only if you expect deductions larger than the standard deduction, or deductions you can take on top of it. The form’s Deductions Worksheet subtracts the standard deduction for you; enter only what is left. Since the new deductions for qualified tips and overtime premium pay came in, Step 4(b) is also where a worker can enter the expected deduction to see it in each paycheck rather than waiting for the refund. Our guides to no tax on overtime and no tax on tips cover how much to enter.

Overstating Step 4(b) is a quiet way to end up owing. Mortgage interest and charitable gifts often feel larger than they turn out to be on Schedule A.

Step 4(c): a fixed extra amount

Step 4(c) adds a flat dollar amount to every paycheck’s withholding, on top of everything else. It is the simplest correction and the easiest to undo. If last year ended with a bill, divide the bill by the number of paychecks left this year and enter that amount. If you are paid every two weeks and start in July, there are about 13 paychecks left, not 26.

Claiming exempt

Writing “Exempt” below Step 4(c) stops federal income tax withholding entirely. It is only allowed if you owed no federal income tax last year and expect to owe none this year. Social Security and Medicare are still withheld. An exempt W-4 expires each year: you must file a new one by the date the IRS sets in mid-February, or your employer will withhold as if you were single with no adjustments.

When to file a new W-4

You never have to file a new form unless your employer asks or you claimed exempt. You should file one when something changes the household’s tax:

• marriage or divorce, which changes the filing status and often adds a second income;
• a birth or adoption, which adds a credit to Step 3;
• a second job, for either spouse;
• side income that has grown past a few thousand dollars;
• a large refund or a bill on last year’s return.

The new form takes effect on the first payroll your employer can process, usually within a pay period or two. Run the numbers again in the autumn: by then most of the year’s withholding has happened and a Step 4(c) amount can still fix the last few paychecks.

State withholding forms

The federal W-4 does not control state withholding. Most states with an income tax have their own certificate, such as California’s DE 4 or Illinois’s IL-W-4, and some accept the federal form. If you change your federal W-4 and your state uses its own form, the state amount stays where it was. Each state paycheck page names the state’s form and shows its withholding.

Every figure on this page is computed by the same code as our calculators. How we calculate.