Gross-Up Calculator (Net to Gross)
Work backward from a target take-home amount to the gross pay you need to run so an employee nets it exactly after federal supplemental tax, FICA, and state withholding.
Gross-Up Calculator (Net to Gross)
Target Net (Take-Home) Pay
The exact amount the employee should receive after tax.
Federal Supplemental Withholding
State + Local Withholding
Leave at 0 for no-income-tax states. Many states publish a flat supplemental rate (for example, California 6.6% / 10.23% for bonuses).
Estimates only, not tax or legal advice. This is the flat-rate supplemental method (exact for flat-rate supplemental wages, an approximation for bracket-based aggregate withholding). Run final numbers through full payroll software.
Keep Clean Pay Records
Timeclock44 logs hours, bonuses, and pay events so you always have the gross and net figures to back up a gross-up. Download the app to track it automatically.
What a Gross-Up Is and When Employers Use It
A gross-up runs payroll in reverse. Normally you start with a gross figure and let taxes shrink it down to a net. A gross-up starts with the net you want the employee to keep and works backward to the gross you have to run. The employer eats the withholding so the take-home equals the promised amount exactly.
This comes up whenever a payment is described to the worker as a clean dollar figure: relocation reimbursements, sign-on and retention bonuses, service awards, and some severance arrangements. Without a gross-up, a promised "$5,000 relocation bonus" would land as roughly $3,500 after supplemental withholding, and the worker would feel short-changed. Grossing up makes the promise whole.
How to Calculate a Gross-Up (the Net-to-Gross Formula)
The flat-rate gross-up comes down to a single equation:
gross = net / (1 - total tax rate)
The total rate is the sum of every withholding percentage as a decimal: federal supplemental, FICA, and any state rate. Take a $500 target net in a no-income-tax state at 22% federal plus 7.65% FICA. The total rate is 0.2965, so the gross is 500 / (1 - 0.2965) = 500 / 0.7035 = $710.73. Withholding is $210.73, and the net checks back to $500.00.
The most frequent slip is forgetting FICA. Add only the federal rate back to the net and the Social Security and Medicare portion goes unfunded, so the take-home falls short. The second mistake is adding the tax percentage to the net instead of dividing: that under-grosses, because the extra pay you tack on is itself taxable. Dividing by (1 - rate) settles that circular dependency in one move.
2026 Tax Rates That Go Into the Formula
The federal flat supplemental rate is 22% on supplemental wages up to $1,000,000 per employee per calendar year, and a mandatory 37% on the portion above $1,000,000 (IRS Publication 15-A). FICA is 7.65%: 6.2% Social Security plus 1.45% Medicare. High earners add 0.9% Additional Medicare on wages over $200,000 year to date (employee side only, with no employer match on that 0.9%).
State supplemental rates vary widely. Many states publish a flat bonus rate (California, for instance, uses 6.6% or 10.23% depending on the payment type), while no-income-tax states sit at 0%. Here's one catch the flat 7.65% hides: once an employee passes the Social Security wage base for the year, the 6.2% no longer applies and the FICA portion drops to 1.45%, so a flat 7.65% over-grosses high earners.
Flat-Rate vs. True Marginal Gross-Up (Limitations)
This tool uses the flat-rate method, which mirrors how the IRS percentage method treats supplemental wages. It's exact for flat-rate supplemental pay (bonuses, commissions, relocation, severance). It's an approximation for a true marginal gross-up, where withholding depends on W-4 settings, graduated brackets, and year-to-date wages (the aggregate method), or where an employee sits near the Social Security wage cap.
For those situations, run the final numbers through full payroll software or your payroll provider. The calculator above is built for fast estimates and sanity checks, not as a stand-in for a formal payroll run. Estimates only, not tax or legal advice.
Frequently Asked Questions
Common questions about gross-up calculator (net to gross)
What is a gross-up in payroll?
A gross-up is when an employer bumps up a payment so the employee nets an exact target amount after taxes come out. Instead of paying $1,000 and letting the employee keep whatever is left, the employer runs a bigger gross figure so the take-home lands on $1,000 on the nose. You see it most often with bonuses, relocation payments, and other one-time supplemental wages.
How do you calculate gross-up from net pay?
Add up every withholding rate as a decimal (federal supplemental, FICA, and any state rate), then divide the target net by one minus that combined rate: gross = net / (1 - total rate). For a $500 target with 22% federal plus 7.65% FICA, that works out to 500 / (1 - 0.2965) = $710.73. The calculator above does this for you and shows each line of withholding.
Why can't I just add the tax percentage back to the net amount?
Because the extra pay you add is itself taxable. If you add 29.65% of $500 ($148.25), the employee still owes tax on that added $148.25, so the take-home comes up short. Dividing by (1 - rate) solves that circular dependency in a single step, and it's mathematically the same answer payroll systems reach by looping.
What tax rate should I use to gross up a bonus in 2026?
The usual starting point is the 22% federal flat supplemental rate plus 7.65% FICA (Social Security and Medicare), for 29.65% before any state tax. Add your state's published supplemental rate if it has one. To compare withholding scenarios on supplemental pay, our overtime tax savings calculator is a handy companion.
When should an employer use a gross-up?
Common cases are relocation reimbursements, sign-on and retention bonuses, service awards, and sometimes severance, anywhere the employer has promised the worker a specific net figure. Grossing up keeps that promise by absorbing the withholding instead of letting taxes shrink the amount.
Does a gross-up include FICA (Social Security and Medicare)?
It should. FICA is 7.65% (6.2% Social Security plus 1.45% Medicare) and it's the piece people forget most often in a gross-up. Leaving it out under-grosses the payment, so the FICA toggle in this calculator defaults to on. High earners may also owe an extra 0.9% Additional Medicare on wages over $200,000 year to date.
What happens to the gross-up rate on bonuses over $1 million?
Once an employee's supplemental wages pass $1,000,000 in a calendar year, the federal flat rate on the portion above that line jumps from 22% to a mandatory 37%. Switch the federal preset to 37% in the calculator to gross up the over-$1M slice.
Is a grossed-up bonus really tax-free for the employee?
Not exactly. The income is still taxable; the employer just covers the withholding so the worker's take-home equals the promised net. The taxes still get paid, they're simply funded by the employer's larger gross payment. For payout math on wages owed, see the final paycheck calculator and back pay calculator.