401(k) Paycheck Calculator (2026)
How much does a 401(k) contribution really cost per paycheck? A pre-tax deferral lowers your federal and state withholding, so your take-home drops by less than the contribution amount. Use the calculator to model your salary, state, filing status, and planned 401(k) deferral with 2026 tax data.
Written by Elena Marquez
Tax Research Lead
Reviewed by Jordan Avery
Lead Editor
Last updated July 3, 2026
Fact-checked: IRS Publication 15-T and 2026 SSA wage-base data
Paycheck calculator with 401(k)
Enter salary and pre-tax deductions
$2,200 credit each (2026)
$500 credit each
2026 federal & state tax rates - Standard deduction applied
How a 401(k) changes your paycheck
Traditional 401(k) contributions are pre-tax. They reduce your federal and state taxable income, which lowers withholding on each check. They do not reduce FICA (Social Security and Medicare), which is always calculated on gross wages before 401(k) deferrals.
- Take-home drops by less than your contribution because of tax savings.
- Federal and state tax withholding decrease proportionally to your bracket.
- FICA stays the same on your full gross salary.
- Employer match is separate and does not come out of your check (it is employer money).
Worked example: $75,000 salary, $6,000/year 401(k)
On a $75,000 salary in Texas (no state income tax) with a $6,000/year 401(k) deferral ($230.77 per biweekly check):
| Metric | Without 401(k) | With $6,000 401(k) |
|---|---|---|
| Annual take-home | $61,391 | $56,711 |
| Biweekly take-home | $2,361.17 | $2,181.17 |
| Total annual tax | $13,610 | $12,290 |
| Biweekly paycheck reduction | $180.00 less per check | |
| Annual tax savings | $1,320 saved on taxes | |
| Effective cost of $6,000 deferral | $4,680 out of pocket (after tax savings) | |
You contribute $6,000 to your 401(k), but your take-home only drops by $4,680 because you save $1,320 in taxes. Read our pre-tax vs post-tax deductions guide for the full breakdown.
2026 401(k) limits
The 2026 employee deferral limit is $24,500, with an $8,000 catch-up contribution for workers age 50 and older. To max out on biweekly pay, contribute about $942.31 per paycheck (26 pay periods).
For retirement account comparisons, see our Roth vs Traditional 401(k) guide. For pay period math, see how many paychecks in a year.
Frequently asked questions
How does a 401(k) contribution affect my paycheck?
If I contribute $500 per paycheck to my 401(k), how much less will I take home?
What is the 2026 401(k) contribution limit?
Does 401(k) reduce Social Security tax?
Should I use a paycheck calculator with 401(k)?
Sources and methodology
By Elena Marquez. Updated for 2026. See our methodology for formulas and assumptions. This is educational information, not tax or legal advice.
Disclaimer | Estimates only. Consult a tax professional for your situation.