Common lifestyle changes, like getting a job or getting married, can change your tax liability. To avoid being caught off guard by an unexpected tax bill or huge tax refund, you’ll need to adjust your withholdings on your paycheck.
What a W-4 does
Every time you earn income, you may owe taxes. Your employer uses Form W-4 to calculate federal income-tax withholding. The current form no longer uses allowances. It accounts for filing status, multiple jobs, credits, other income, deductions, and extra withholding. Payroll cannot see your whole household, so a form that looks reasonable for one paycheck may fall short across two jobs.
When you have too much money withheld from your paychecks, you are giving the government an interest-free loan and getting it back as a refund. Many people would rather have that money in each paycheck. On the other hand, having too little withheld from your paycheck could mean an unexpected tax bill or even a penalty for underpayment. Either way, there’s a better way to manage your hard-earned money.
The key to paying the right amount of tax is to update your W-4 regularly. Do this whenever you have a major personal life change. The goal is to reduce the potential for both a tax bill and a tax refund to zero, or close to it. But if you count on a big tax refund every year, you should also pay attention to your withholding, because how much you have withheld directly impacts your refund.
Five life changes that mean it is time to update your W-4
You get a second job
A second job is one of the most common reasons for needing to adjust your W-4. Do this whether you moonlight, have a home business, or get another full-time job. Any time your income goes up, your tax liability will likely go up too, requiring a new W-4. If your extra income comes from a side job with no W-4, you can still adjust the W-4 at your main job to account for the increase in income.
Your spouse gets a job or changes jobs
Any change of household income, whether up or down, can change the amount joint filers should have withheld. Look at both incomes together. Use Step 2 or the IRS estimator to coordinate the forms, and avoid claiming the same dependents or deductions on both jobs. The current W-4 instructions explain which entries generally belong on the highest-paying job.
You are unemployed part of the year
If you get laid off or return to work after a gap, your full-year income and withholding can look quite different from what payroll assumes. Include unemployment compensation and any withholding on it. Use current paystubs and the estimator to account for the part of the year already gone by; do not assume that being out of work automatically means you have overpaid.
You get married or divorced
Tying or untying the knot can change your filing status, credits, and overall tax calculation, especially if both spouses work. Marriage does not automatically mean a lower tax bill. Review the whole household and update your expected filing status and other entries when necessary.
You have a baby or adopt a child
A new baby is more than a bundle of joy. It is a tax event too. You may qualify for child-related or adoption credits, depending on the rules and your circumstances. Step 3 of the current W-4 accounts for anticipated credits. Check eligibility rather than simply adding an allowance, and coordinate the entry if there are multiple jobs.
How to make the adjustment
If you want more or less taken out of each paycheck, give your employer an updated W-4. Extra withholding is a dollar amount per pay period in Step 4(c). For a decrease, use the estimator rather than guessing. Check a later paystub to confirm that payroll applied the change.
You can adjust your W-4 at any time during the year. Just remember, adjustments made later in the year will have less impact on your taxes for that year.
Current instructions: IRS Form W-4 and the IRS Tax Withholding Estimator. Ask us about your withholding.
How to complete the current Form W-4
Step 1: Your information and filing status
Enter your identifying information and the filing status you expect to use. This gives payroll a starting point. It does not account for everything else going on in your household.
Step 2: Multiple jobs or a working spouse
If you have two jobs, or you file jointly and your spouse works, pay attention here. Each employer only sees its own paycheck. Without an adjustment, the combined withholding can fall short. The form offers an estimator and a checkbox option for certain two-job households. The options are not interchangeable for every situation.
Step 3: Dependents and other credits
This step accounts for anticipated tax credits. It does not claim the old withholding allowances, and each dependent does not simply reduce taxable income. With multiple jobs, avoid counting the same credits on every W-4. Follow the current form’s instructions for which job should carry these entries.
Step 4: Other income, deductions, and extra withholding
Step 4(a) can account for income without withholding. Step 4(b) adjusts for qualifying deductions. Step 4(c) is where you request an additional dollar amount withheld from each paycheck. That amount is per pay period, so pay frequency matters.
Step 5: Sign, date, and give it to payroll
Step 5 is the signature. Extra withholding goes in Step 4(c). Give the completed form to your employer. Check a subsequent paystub to see whether the change took effect.
The 2026 form also has a checkbox for exemption from withholding. Use it only if you meet both eligibility conditions in the current instructions; it is not a way to opt out of tax.