How to adjust your W-4 so you don't owe at tax time

How withholding is figured

Your employer does not know your whole tax picture. It takes the pay on one check, multiplies it out to a year, subtracts a built-in deduction, runs the result through the IRS withholding tables in Publication 15-T and divides by the number of paychecks. The W-4 is how you tell it what that formula misses. If the form is right, the federal tax withheld over the year lands close to the tax on your return, and you get neither a large refund nor a bill.

A single filer earning $60,000 with one job and a W-4 that fills in only step 1 has about $5,020 withheld over the year. The 2026 return for that income shows $5,023 of federal tax: about even. The default form works well for one job, wage income only and the standard deduction ($16,100 single, $32,200 married filing jointly, $24,150 head of household in 2026).

What each step of the 2026 W-4 does

• Step 1, filing status. Picks the deduction and tax brackets used for withholding. Single and married filing separately use the same tables; head of household and married filing jointly get larger ones.
• Step 2, multiple jobs or spouse works. For two or more jobs at once, or a married couple who both work. You can use the IRS estimator, the Multiple Jobs Worksheet (its result goes in step 4(c)), or, with exactly two jobs, check a box on both W-4s. The box cuts the standard deduction and brackets in half for each job; the form says it is accurate for jobs with similar pay and withholds more than needed when the pay is far apart.
• Step 3, dependents and other credits. $2,200 per child under 17 and $500 per other dependent if your income is $200,000 or less ($400,000 joint), plus other credits you expect, such as education credits. The total comes straight off your yearly withholding.
• Step 4(a), other income. Income that is not from a job, such as interest, dividends or retirement income, so tax on it is withheld from your pay. The form says not to include self-employment income here.
• Step 4(b), deductions. Deductions beyond the standard deduction, from the worksheet on page 4 of the form. For 2026 that worksheet includes itemized deductions and the new deductions for tips and overtime, car loan interest and seniors, along with student loan interest and IRA contributions.
• Step 4(c), extra withholding. A flat dollar amount added to every paycheck. It is the simplest way to fix a shortfall.

For the single filer earning $60,000, paid every two weeks, here is what each entry does to one paycheck:

Federal income tax withheld per paycheck, 26 paychecks a year, 2026 Publication 15-T percentage method. Each row changes one entry from the default.

A step 3 credit lowers each check by the credit divided by 26 ($84.62 for one child). Steps 4(a) and 4(b) move withholding by the amount times your withholding rate, here 12%. The step 2 box is the biggest lever: $144.80 more per check for someone who, alone, would not need it.

Two jobs: a common reason people owe

Each employer withholds as if its job were the household's only income, so each one applies the full married standard deduction and the low brackets. A couple earning $80,000 and $50,000 ($130,000 together) who both file a W-4 marked married filing jointly, with step 2 blank:

Federal income tax for 2026, married filing jointly, standard deduction, wages only. Both W-4s marked married filing jointly; paid every two weeks.

With step 2 blank, about $4,223 is due in April. Checking the box overshoots, because the two salaries are not equal, and the couple gets about $1,347 back. A closer fix is to leave the box blank and add $163 per paycheck in step 4(c) on the higher-paying job: that brings withholding to $11,258 against $11,243 owed.

Fixing it late in the year

Step 4(c) works on the paychecks that remain. The same $4,223 shortfall spread over 6 paychecks takes about $704 each. Next January, drop back to $163 so you do not over-withhold the following year.

Owing at filing is not always a penalty problem. Under IRS Publication 505, you generally avoid the underpayment penalty if you owe less than $1,000 after withholding and refundable credits, or if your withholding covers the smaller of 90% of this year's tax or 100% of last year's. If last year's AGI was over $150,000 ($75,000 married filing separately), the prior-year test is 110%. Withholding is generally treated as paid evenly through the year, so raising it late in the year also counts toward the earlier quarters.

Kids: step 3 and your refund

A head of household earning $65,000 with 2 children under 17 can enter $4,400 in step 3. Leaving it blank has about $4,548 withheld against a tax bill of $151 after the child tax credit, so about $4,397 comes back as a refund. Entering the credit raises each paycheck by about $169.23, and the return comes out about even. Both choices cost the same in tax; the difference is whether you get the money through the year or in one refund.

Only one W-4 in the household should claim the credits. If both spouses work, put step 3 on the higher-paying job's form, as the form's instructions advise.

Side income: step 4(a) or step 4(c)

A single filer earning $75,000 who also has $10,000 of interest, dividends or other non-job income owes about $2,200 more federal tax on it. With no change to the W-4, about $2,206 is due at filing. Either entry fixes it:

Single filer, 2026, standard deduction, other income taxed as ordinary income. Self-employment income also owes self-employment tax, which these figures leave out.

Step 4(a) lets the withholding formula tax that income at your withholding rate, so you do not have to work out a dollar amount. Step 4(c) keeps the income off the form you hand your employer, which the W-4 instructions mention as an option for privacy. Freelance and gig income is different: the form says not to list self-employment income in step 4(a), and you also owe self-employment tax on it, so the W-4 points those workers to the IRS estimator, and Form 1040-ES covers quarterly estimated payments instead.

When to file a new W-4

File a new form when you marry or divorce, have a child, start or lose a second job, pick up income with no withholding, or start itemizing. The paycheck calculator shows what a new W-4 does to each check, and the income tax calculator shows whether this year's withholding will cover your return. A large bonus can shift the picture too; see how bonuses are taxed.