RSU Tax Calculator

Vesting is the moment your Restricted Stock Units (RSUs) become taxable, and estimating that liability ahead of time keeps you from being caught off guard. A solid estimate supports your budget, helps you sidestep underpayment penalties, and gives you a clearer footing when deciding whether to sell the shares or hang on to them.

On the vesting date, the fair market value of the shares counts as ordinary income and is hit with income tax along with Social Security and Medicare. The calculator multiplies that vested value by the federal bracket and state rate you enter, then adds Social Security at 6.2% on up to $184,500 (the 2026 wage base, applied as if the RSUs were your only wages) and Medicare at 1.45%. It does not model what your employer withholds, which is often a flat 22% federal supplemental rate (37% on supplemental wages above $1 million in a year) and can sit well below your bracket.

State and local taxes deserve a place in your planning too, since they can move your total bill substantially depending on where you live. And because withholding at vesting often falls short of what you ultimately owe, you may find a balance still due when you file.