Net Worth
$385KTop 42%PeakWorth
$4.2M+$182KNet Worth
$385KTop 42%PeakWorth
$4.2M+$182KFI Age
50y 1m-11moSupplemental withholding, FICA, state tax, and 401(k) deferral. See what's left of any bonus — and what to do with it.
Federal supplemental rate
22% (37% over $1M)
FICA on bonus
7.65%
Typical bonus haircut (mid state)
~38–42%
401(k) deferral allowed?
Usually yes
The IRS treats bonuses as 'supplemental wages' and withholds at a flat 22% federally (37% on amounts over $1M in a year), plus 7.65% FICA, plus your state's rate. A $20,000 bonus in California can land closer to $11,500 — even though your marginal tax rate may not actually be that high.
Employers can use the percentage method (flat 22%) or the aggregate method (treat the bonus + your normal paycheck as if it were ongoing income, then withhold based on your W-4). Both methods are legal and the over- or under-withholding washes out at tax time — but the cash you see on payday differs significantly.
If your 401(k) plan allows it, deferring a portion of the bonus into your 401(k) (and HSA, if eligible) reduces both federal and state tax today AND fast-forwards your FI Age. The calculator shows exactly how much of the bonus you keep at each deferral %, so you can pick the split between cash now and freedom later that fits your situation.
A calculator alone tells you the payment. PeakWorth tells you what that payment costs your retirement — and how every change ripples through the next 30 years of your finances.
No — it's only withheld at a higher rate. Your true tax rate on the bonus is determined at year-end on your full income. Over-withholding shows up as a refund.
You can defer it into your 401(k), HSA, or charitable giving to reduce taxable income — but you can't avoid FICA on cash compensation.
Learn guides, true-cost calculators, and audience playbooks across the PeakWorth network.
Decision guide
How to allocate a bonus
Pre-tax, debt, invest, lifestyle — the right order.
Benchmarks
Net worth by age in California
2026 benchmarks adjusted for high cost of living.
Built for
PeakWorth for equity-comp employees
RSUs, options, and AMT — model the after-tax exit.
Compare
PeakWorth vs J.P. Morgan Automated Investing
Chase-app robo at 0.35% vs the household plan above.
Benchmarks
Income by age
Median individual & household income at every age.
Benchmarks
Average income in America
Mean, median, and the full income distribution.
PeakWorth includes every loan calculator above — connected to your real income, expenses, and goals. Every number you change updates your live FI Age and lifetime projection.
