About the RSU Tax Calculator
This RSU tax calculator shows what you really owe when restricted stock units vest. The value of the shares on the vest date is ordinary wage income, taxed like salary for federal income tax, Social Security, Medicare and state tax. Enter the number of shares vesting, the price on the vest date and your other income for the year, and the calculator compares your actual tax on that income with what your employer withholds.
Employers usually withhold federal tax on RSUs at the flat 22% supplemental rate (37% on supplemental wages above $1 million in a year). If your income puts the vest in the 24%, 32%, 35% or 37% bracket, 22% is not enough and you will owe the difference when you file — sometimes thousands of dollars. The calculator estimates that shortfall, the number of shares sold to cover withholding, and the shares you keep.
Federal tax uses the 2026 brackets and standard deduction from IRS Rev. Proc. 2025-32 and the $184,500 Social Security wage base; enter other income as your wages and other taxable income before the RSUs. It assumes you take the standard deduction, treats that other income as wages from the same employer, and uses your marginal state rate as a flat rate on the vest. Your cost basis in the shares you keep equals the vest-date price, so later gains or losses are capital gains from that point.
With the default inputs, the extra tax to pay at filing is $600.00. Change any value above to recalculate instantly.
How to use the rsu tax calculator
- 1Enter the number of shares vesting and the price on the vest date.
- 2Choose your filing status and enter your other income for the year.
- 3Enter any bonuses or vests already paid this year.
- 4Check the withholding rates your employer uses (22% federal is typical).
- 5Read the shortfall and plan an estimated payment or W-4 change if it is positive.
Formula and method
RSUs are taxed as wages when they vest: the number of shares times the market price on the vest date is added to your income. The true federal cost is the difference between the tax on your income with and without the vest, using the 2026 brackets and standard deduction, so it reflects every bracket the vest spans.
Employers usually withhold at the 22% flat supplemental rate, switching to a mandatory 37% for supplemental wages over $1 million in the calendar year. Social Security (6.2% up to the 2026 wage base of $184,500) and Medicare (1.45%) are withheld too. The employer also withholds 0.9% Additional Medicare Tax on wages above $200,000 whatever your filing status, while the tax you actually owe starts at $200,000 single or head of household, $250,000 joint and $125,000 separate; the difference is included in the shortfall. The calculator treats your other income as wages from the same employer (so it uses up the Social Security wage base first) and ignores a spouse’s wages. Shares sold to cover are rounded up to whole shares.
- FMV
- Fair market value per share on the vest date
- T(x)
- Federal tax on taxable income x (2026 brackets)
- std
- Standard deduction for your filing status
Worked examples
200 shares at $150, $150k salary, single
The $30,000 vest falls entirely in the 24% bracket, so federal tax is $7,200 but only $6,600 (22%) is withheld — a $600 shortfall. FICA is $2,295 and state withholding matches state tax, so 70 shares are sold to cover and you keep 130.
$250k vest on a $300k salary, married
The vest pushes joint taxable income from $267,800 to $517,800, spanning the 24%, 32% and 35% brackets for $69,300.50 of federal tax. With only $55,000 withheld at 22%, and state withholding a little above state tax, about $11,976 is still due at filing.
Small vest in the 12% bracket
With $40,000 of other income the $5,000 vest is taxed at 12% ($600), but 22% ($1,100) is withheld, so about $500 comes back as a refund.
Married couple crossing $200,000 of wages
The $50,000 vest stays in the 22% joint bracket, so the $11,000 withheld matches the tax. Only $4,500 of wage base is left, so Social Security is $279 plus $725 of Medicare. The employer also withholds 0.9% on the $30,000 above $200,000 ($270), but a joint return owes Additional Medicare Tax only above $250,000, so that $270 is refunded.
Frequently asked questions
How are RSUs taxed?+
RSUs are taxed as ordinary income when they vest, based on the share price that day. The value appears on your W-2 and is subject to federal income tax, Social Security, Medicare and state tax. When you later sell, any change from the vest price is a capital gain or loss.
Why do I owe tax on RSUs at filing time?+
Employers typically withhold federal tax on RSUs at a flat 22%. If your total income puts you in the 24% bracket or higher, the withholding falls short and you owe the difference when you file.
What is sell to cover?+
Sell to cover means your employer sells just enough of the vesting shares to pay the required tax withholding and delivers the rest to you. Other options are net share settlement or paying the withholding in cash.
Are RSUs taxed twice?+
No. You pay income tax on the value at vest, and that value becomes your cost basis. When you sell, you only pay capital gains tax on growth above the basis. Make sure your 1099-B basis is adjusted, or you could overpay.
Should I sell RSUs as soon as they vest?+
Selling immediately creates little or no extra tax because the basis equals the vest price, and it reduces concentration in your employer’s stock. Holding over a year turns later growth into long-term gains, but adds single-stock risk.
Tax results are estimates based on published rules and simplified assumptions. They are not tax advice — check official guidance or a tax professional for your situation.