# 401(k) vs take-home pay (2026)

A traditional 401(k) deferral lowers federal (and usually state) taxable wages, so income tax withholding falls — but Social Security and Medicare generally still apply to the deferred amount. Below is the same $80,000 California single sample at 0% and 10% using the Takehome Cash engine.

Ten percent of $80,000 is $8,000 deferred. That money is still yours in the plan; it is not “tax” on this page. Net take-home drops by less than $8,000 because federal and California tax are computed on the remaining wages. FICA is almost unchanged if you have no cafeteria-plan health premium.

Roth 401(k) is not modeled: Roth deferrals do not reduce federal wages. Employer match does not appear on the employee stub as cash, so it is omitted. Annual IRS elective-deferral limits can cap a high-percent election; we do not enforce the dollar cap in v1.

The calculator starts at 10% so you can drag the percent toward zero and watch federal and state lines move. Health premiums (section 125) reduce FICA as well as income tax — a different lever than 401(k). Estimates only, reviewed August 23, 2026.

## Sample estimates

### $80k CA single, 0% 401(k)

- Gross: $80,000.00
- Federal income tax: $8,770.00
- Social Security: $4,960.00
- Medicare: $1,160.00
- State income tax: $3,210.42
- Net / take-home: $61,899.58 (effective tax 22.6%)
- Per paycheck net: $61,899.58 (1 periods)

### $80k CA single, 10% 401(k)

- Gross: $80,000.00
- Federal income tax: $7,010.00
- Social Security: $4,960.00
- Medicare: $1,160.00
- State income tax: $2,547.85
- Net / take-home: $56,322.15 (effective tax 19.6%)
- Per paycheck net: $56,322.15 (1 periods)

Label: engine estimates, not pay stubs.

## FAQ

### Does a 401(k) reduce Social Security tax?

Usually no. Traditional elective deferrals stay in the Social Security and Medicare wage base. Pre-tax health premiums under a cafeteria plan generally reduce FICA wages.

### What sample is shown?

$80,000 annual, California, single, 0% vs 10% traditional 401(k), no health premium, no extra withholding.

### Is the 10% contribution gone?

It is withheld from the check and sent to the plan. This page reports cash take-home, not total compensation.

## Related

- [$80,000 salary take-home](https://takehomecash.com/80000-salary-take-home-pay/index.md)
- [California paycheck calculator](https://takehomecash.com/california-paycheck-calculator/index.md)
- [Methodology](https://takehomecash.com/methodology/index.md)