Quick answer: Form W-4 tells your employer how much federal tax to withhold from each paycheck. The current version has no allowances and no exemptions. If you have one job and take the standard deduction, you complete Step 1 and Step 5 and skip the rest. Everything else on the form exists for three situations: multiple jobs or a working spouse, dependents, and other income or deductions. The fastest way to get it right is the IRS Tax Withholding Estimator at irs.gov.
Key Takeaways
- The current W-4 has no allowances; advice about “claiming two” refers to a form retired in 2020
- One job and standard deduction? Complete only Step 1 and Step 5
- Step 2 is where most errors happen: each job withholds as if it is your only income
- Complete Steps 3 and 4 on one W-4 only, normally the highest-paying job
- To fix a mid-year shortfall, divide it by remaining paychecks and enter that on line 4(c)
Extra Withholding Calculator (Line 4c)
If you are on track to owe in April, this shows the dollar amount to enter on line 4(c) so the shortfall is covered by year-end.
This is arithmetic on the number you supply, not a tax projection. Get your shortfall estimate from the IRS Tax Withholding Estimator or last year’s return, then use this to convert it into a per-paycheck amount. Submit a fresh W-4 in January without the extra amount, or you will over-withhold next year.
Why the form changed and why old advice is wrong
If someone tells you to “claim two allowances,” they are describing a form that no longer exists. The IRS redesigned the W-4 in 2020 to remove withholding allowances entirely, because the concept was tied to personal exemptions that the 2017 tax law eliminated.
The replacement asks for dollar amounts rather than a count. Instead of translating your situation into a number of allowances and letting a table do the work, you now enter estimated dependent credits, other income, and deductions directly. The result is more accurate for most people but confusing for anyone applying old rules of thumb.
You are not required to submit a new W-4 just because the form changed. Your employer continues using whatever is on file. But if your withholding has been wrong, or your life has changed, filing a new one is the only way to fix it.
The five steps, and which ones apply to you
Step 1: Personal information and filing status. Everyone completes this. Your filing status here should match what you will use on your return.
Step 2: Multiple jobs or spouse works. This is where most withholding errors originate. Each job withholds as though it is your only income, so two jobs each withholding correctly in isolation will together withhold too little. Complete this step if you hold more than one job or file jointly with a working spouse.
Step 3: Claim dependents. Multiply qualifying children under 17 by the child tax credit amount and other dependents by the credit for other dependents, then enter the total. This reduces withholding.
Step 4: Other adjustments. Optional. Line 4(a) is other income not from jobs, such as interest, dividends, or retirement income, and increases withholding. Line 4(b) is deductions beyond the standard deduction and decreases it. Line 4(c) is extra withholding per paycheck, a flat dollar amount, and is the simplest lever for fine-tuning.
Step 5: Sign. The form is not valid unsigned.
Handling multiple jobs without overcomplicating it
Step 2 offers three methods, and choosing among them causes needless difficulty.
The estimator at irs.gov is the most accurate and takes about ten minutes with recent pay stubs in hand. Use it if the amounts matter to you.
The multiple jobs worksheet on page 3 produces a similar result on paper.
The checkbox in Step 2(c) is the simplest option: if there are exactly two jobs in the household with roughly similar pay, check the box on both W-4s. It is less precise than the other methods but far better than leaving Step 2 blank, which is what most people do.
One rule applies regardless of method: complete Steps 3 and 4 on only one W-4, normally the highest-paying job. Claiming dependents on both jobs is a common error that produces a large April bill.
Situations that reliably produce a surprise bill
- A spouse started working mid-year and neither W-4 was updated
- A second job or significant freelance income with nothing entered on line 4(a)
- A large bonus, which is often withheld at a flat supplemental rate lower than your actual marginal rate
- Investment or retirement income with no withholding at source
- A child turning 17, which changes the credit and therefore Step 3
- Marriage or divorce without updating filing status
The IRS recommends a withholding checkup whenever any of these occur, rather than waiting until filing season to discover the result.
Adjusting mid-year, and the math that catches people
A W-4 change applies only to future paychecks. If you discover in October that you are $1,200 short, that amount must be withheld across the remaining pay periods, not spread across the year. With four paychecks left, that is $300 each, entered on line 4(c).
The general formula: divide the shortfall by the number of paychecks remaining in the year and enter that figure as extra withholding. Then submit a fresh W-4 in January without the extra amount, otherwise you will over-withhold for the following year.
Some people deliberately over-withhold to force a refund. That works, though it is an interest-free loan to the government. The opposite approach, aiming to owe a small amount, requires staying under the underpayment penalty thresholds, which generally means paying at least 90% of the current year’s tax or 100% of last year’s, whichever is smaller.
How to submit and check the result
Submit the new W-4 to your employer’s payroll department or through the HR system; it does not go to the IRS. Then verify it worked: check the federal withholding line on your next pay stub and compare it to the previous one. Payroll changes occasionally fail to take effect, and the pay stub is the only confirmation that matters.
Two weeks after the change, run the Tax Withholding Estimator again using the new numbers. If the projection lands close to zero owed or a small refund, the W-4 is doing its job.
FAQ
Can I still claim exempt? Only if you had no tax liability last year and expect none this year. Write “Exempt” below line 4(c), and note that exempt status must be renewed every year by mid-February.
Does a W-4 affect Social Security and Medicare taxes? No. Those are fixed percentages and are not affected by anything on the form.
How often can I submit a new W-4? As often as you need to. Employers must process a valid form promptly.
Do I file a W-4 for a side gig paid on a 1099? No. Contractor income has no withholding; you handle it through quarterly estimated payments or by increasing withholding at your W-2 job using line 4(a).
Where do I find the estimator? Search “Tax Withholding Estimator” on irs.gov. Have your most recent pay stubs and last year’s return available.
Sources
Last updated: August 18, 2026. Written by the InfoBrief Editorial team. Policies and prices change; confirm with the official source before acting. See our disclosure.