# What should I put on my W-4?

Works out what to enter in Form W-4 (2026) Steps 3 and 4, the federal tax each paycheck then withholds, and the Step 4(c) extra amount that makes the year’s withholding match your tax.

- Page: https://www.acalculator.org/finance/w4-calculator
- JSON spec: https://www.acalculator.org/finance/w4-calculator.json
- Version: 979fc070f262

## Default answer

Example with the default inputs (Filing status (Step 1c) Single or married separately, Taxable pay a paycheck $2,500.00, Pay frequency Every two weeks, Two jobs, or a working spouse (Step 2c) No, Children under 17 0, Other dependents 0, Interest and dividends a year $0.00, Other income a year $0.00, Itemized deductions a year $0.00, Federal tax withheld so far $0.00, Paychecks left this year 26, Today September 30, 2026) on the example date Wednesday, September 30, 2026: Put $0.00 in Step 3 and $0.12 in Step 4(c); each paycheck then withholds $216.15 plus the extra.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| status | Filing status (Step 1c) | The filing status you will use on your tax return. |
| wages | Taxable pay a paycheck | Pay per paycheck from this job less pre-tax 401(k), health, and HSA deductions. |
| freq | Pay frequency | How often this job pays you. |
| twoJobs | Two jobs, or a working spouse (Step 2c) | You check the Step 2(c) box because two jobs pay about the same. |
| kids | Children under 17 | Qualifying children under 17: $2,200 each in Step 3. |
| deps | Other dependents | Other dependents: $500 each in Step 3. |
| invest | Interest and dividends a year | Taxable interest and dividends with no withholding (part of Step 4(a)). More than $12,200 rules out the earned income credit. |
| other | Other income a year | Other yearly income with no withholding, such as a pension or unemployment (part of Step 4(a)); not interest or dividends. |
| itemized | Itemized deductions a year | Your expected itemized deductions; the part over the standard deduction goes in Step 4(b). |
| ytd | Federal tax withheld so far | Federal income tax withheld this year up to now. |
| left | Paychecks left this year | Paychecks still to come this year, which the new W-4 applies to. |
| date | Today | Today’s date: its year is the tax year. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| step4c | Step 4(c) extra withholding | Extra federal tax per paycheck that brings the year’s withholding up to the year’s tax (0 when it already covers it). |
| step3 | Step 3 amount | $2,200 per child under 17 plus $500 per other dependent. |
| step4a | Step 4(a) other income | Yearly other income with no withholding. |
| step4b | Step 4(b) deductions | Itemized deductions over the 2026 standard deduction for the filing status. |
| withholding | Withholding a paycheck | Federal tax withheld per paycheck with Steps 2 to 4(b) filled in, before Step 4(c) (Pub 15-T). |
| projected | Withholding for the year | Withheld so far plus the withholding a paycheck times the paychecks left. |
| tax | Federal income tax for the year | Tax after credits on Form 1040. |
| rates | Tax year | The tax year of the form and tables used. |
| refund | Refund at this withholding | Withholding for the year less the tax, before Step 4(c): below 0 is the amount owed. |

## Method

Step 3 = $2,200 × children under 17 + $500 × other dependents. Step 4(a) = other income. Step 4(b) = itemized deductions − the standard deduction, not below 0. Withholding a paycheck = Pub 15-T Worksheet 1A with those entries. Tax = Form 1040 tax on pay × paychecks a year + other income, after credits. Step 4(c) = max(0, tax − (withheld so far + withholding × paychecks left)) ÷ paychecks left.

## Assumptions

- An estimate, not tax advice. 2026 federal rates (Rev. Proc. 2025-32), Form W-4 (2026), and Pub 15-T (2026).
- The job pays the same every paycheck all year; with two jobs, run it for the higher-paying job and include the other job’s pay as other income, or check Step 2(c) on both W-4s when they pay about the same.
- Step 3 uses the full credits (the W-4 limits Step 3 to incomes of $200,000, or $400,000 jointly, or less). Step 4(b) counts itemized deductions only; the 2026 Deductions Worksheet also takes tips, overtime, car loan interest, and the senior deduction, which are not modelled.
- Not modelled: self-employment tax, capital gains rates, AMT, the premium tax credit, and education credits. Additional Medicare Tax is withheld separately and left out.

## Worked examples

1. status = single, wages = $2,500.00, freq = biweekly, left = 26, date = 2026-01-02 gives step3 = $0.00, step4b = $0.00, withholding = $216.15, projected = $5,620.00, tax = $5,623.00, step4c = $0.12. Source: IRS Form W-4 (2026), Pub 15-T (2026) Worksheet 1A, Rev. Proc. 2025-32.
2. status = mfj, wages = $4,000.00, freq = semimonthly, kids = 2, other = $10,000.00, itemized = $40,000.00, ytd = $1,000.00, left = 12, date = 2026-07-01 gives step3 = $4,400.00, step4a = $10,000.00, step4b = $7,800.00, withholding = $126.00, projected = $2,512.00, tax = $3,027.00, step4c = $42.92. Source: IRS Form W-4 (2026), Pub 15-T (2026) Worksheet 1A, Rev. Proc. 2025-32.
3. status = hoh, wages = $3,000.00, freq = biweekly, twoJobs = yes, kids = 1, ytd = $2,000.00, left = 13, date = 2026-07-01 gives step3 = $2,200.00, withholding = $346.75, projected = $6,507.75, tax = $3,911.00, refund = $2,596.75, step4c = $0.00. Source: IRS Form W-4 (2026), Pub 15-T (2026) Worksheet 1A, Rev. Proc. 2025-32.

## FAQ

### How do I fill out a W-4?

Step 1: your name and filing status. Step 2: check the box only if you have two jobs at once, or are married filing jointly and your spouse works, and the jobs pay about the same. Step 3: $2,200 for each child under 17 and $500 for each other dependent. Step 4: other income in 4(a), deductions above the standard deduction in 4(b), and any extra tax per paycheck in 4(c). Step 5: sign it.

### What should I put in Step 3 of the W-4?

For 2026, multiply your children under 17 by $2,200 and your other dependents by $500, and add the two. Use Step 3 only if your income is $200,000 or less ($400,000 or less if married filing jointly).

### What is Step 4(c) on the W-4?

An extra amount of federal income tax withheld from every paycheck. Use it when the regular withholding would leave you owing tax, for example because of a second job, side income, or a big bonus. This calculator works out the amount that brings this year’s withholding up to your tax.

### What goes in Step 4(b)?

Deductions you expect to take beyond the standard deduction: itemized deductions minus the 2026 standard deduction ($16,100 single, $32,200 married filing jointly, $24,150 head of household). The 2026 form’s Deductions Worksheet also has lines for the deductions for tips, overtime, car loan interest, and seniors.

### Should I check the Step 2 box?

Check it when you hold two jobs at once, or are married filing jointly and both of you work, and the two jobs pay about the same. It withholds as if each job paid half of a combined income. If the pay is very different, use the IRS Tax Withholding Estimator or the Multiple Jobs Worksheet instead, and check the box on no W-4.

### How often can I change my W-4?

Whenever you like. Give your employer a new form; it must use it no later than the start of the first payroll period ending on or after the 30th day after you hand it in. It is worth checking after a raise, a new child, marriage, or a second job.

## Sources

- IRS, Form W-4 (2026), Employee’s Withholding Certificate: Step 3 amounts ($2,200 and $500) and income limits. https://www.irs.gov/pub/irs-pdf/fw4.pdf
- IRS, Publication 15-T (2026), Worksheet 1A and the Annual Percentage Method tables. https://www.irs.gov/pub/irs-pdf/p15t.pdf
- IRS, Revenue Procedure 2025-32 (tax year 2026 brackets and standard deductions). https://www.irs.gov/irb/2025-45_IRB
- IRS, Publication 505 (2026), Tax Withholding and Estimated Tax. https://www.irs.gov/publications/p505