Pre-tax retirement savings shrink your taxable income, so each dollar saved costs you less than a dollar of take-home pay.
401(k) rate
Saved per year
Federal tax
Take-home
0%
$0
$390
$18,080
5%
$1,000
$290
$17,180
10%
$2,000
$190
$16,280
15%
$3,000
$90
$15,380
With state income tax
State tax depends on where you live. These rows show the effect of a flat rate on top of federal taxes; plug your own state's rate into the paycheck calculator.
About $18,080 for a single filer in a state with no income tax, based on 2026 federal brackets, Social Security and Medicare. That is $1,506.67 a month or $695.38 every two weeks.
What tax bracket is $20,000 in?
For a single filer, after the standard deduction the top dollars are taxed at 10%. The average federal income tax rate is much lower, 1.9%, because lower brackets apply first.
How much does a 401(k) save in tax?
Putting 10% ($2,000) into a traditional 401(k) lowers federal income tax by about $200 a year for a single filer, so take-home pay drops by less than the amount you save.