RSU Tax Calculator (2026)
When restricted stock units vest, the share value becomes taxable wages immediately. Enter your vesting details to estimate how much will be withheld and how many shares you'll actually keep.
California's supplemental rate for equity compensation is 10.23% — enter that if you're in CA, your own state's rate otherwise, or 0 for no-tax states.
| Vest value (taxable income) | $0 |
| Federal withholding | $0 |
| Social Security | $0 |
| Medicare | $0 |
| State withholding | $0 |
| Estimated net value | $0 |
| Approx. shares sold to cover | 0 |
| Approx. shares you keep | 0 |
Uses the 2026 federal supplemental rate (22%, 37% above $1M), Social Security up to the $184,500 wage base, and Medicare including the 0.9% additional tax over $200,000. Withholding is not your final tax liability.
About this estimate
The calculator models the standard "sell to cover" withholding most employers apply at vest. Federal tax is withheld at the IRS flat supplemental-wage rate of 22%, switching to the mandatory 37% on any supplemental wages beyond $1 million in the year — your year-to-date wages input is what tells the calculator how close you are to that line and to the $184,500 Social Security wage base, which is why the same vest can withhold very differently in January versus December. Medicare has no cap, and employers add the 0.9% additional Medicare withholding once total wages pass $200,000, regardless of filing status. Shares sold to cover are rounded up to whole shares, as brokers do.
Two things this deliberately is not: a projection of your final tax bill (the flat 22% withholding routinely under-collects for people in the 32%-and-up brackets, who settle the difference at filing), and a state tax engine — you supply your state's supplemental rate because states publish different rates for equity compensation, such as California's 10.23%. Rates come from IRS Publication 15 and state withholding schedules; source URLs live alongside the data in the site repository.
Frequently asked questions
How are RSUs taxed when they vest?
The market value of the shares on the vest date is ordinary W-2 income. It is subject to federal income tax, Social Security, and Medicare, plus state income tax where applicable. Most employers withhold by selling a portion of your shares ("sell to cover").
Why is RSU withholding 22%?
Employers typically withhold federal tax on RSUs at the IRS flat supplemental-wage rate of 22% (37% on supplemental wages above $1 million in a year). If your actual marginal bracket is higher than 22%, the withholding may fall short and you can owe more at filing time.
Do I pay taxes again when I sell the shares?
Only on the change in price after vesting. Your cost basis is the vest-date value that was already taxed as income. Selling later for more creates capital gain; selling for less creates a capital loss.
Is this calculator exact?
No — it estimates standard withholding. Your employer may use different methods, your Social Security wage base may already be met, and your final tax bill depends on your full return. Treat it as a planning estimate, not tax advice.
Further reading: RSU taxes, explained — sell-to-cover mechanics, the under-withholding trap, and the cost-basis mistake that taxes the same dollars twice.