RSU Vesting & Tax Calculator
Turn a restricted stock unit grant into a dated plan: how many shares release on each vest date, what they are worth at your assumed share price, how much payroll holds back for federal, FICA and state tax, and the net value you actually keep.
Grant details
Your tax situation
How to use this calculator
1. Enter the grant the way your offer letter states it
New-hire packages are usually quoted as a dollar amount that gets converted to shares at a price set on the grant date, while annual refreshers are more often handed out as a share count. Pick whichever matches your paperwork — the dollar mode divides by today's price to get the share count, and the whole plan works from there.
2. Match the vesting schedule
Four equal annual chunks is the classic. Back-loaded 5/15/40/40 schedules push most of the value into years three and four, which is a retention device worth spotting before you sign. Cliff-then-monthly is the standard in tech: nothing for twelve months, a quarter of the award in one go, then a slice every month afterwards.
3. Be honest about the price assumption
Growth compounds against every future vest date, so an optimistic number quietly inflates years three and four the most. Run the plan at 0% first — that is the only figure you actually know — then treat anything above it as upside rather than salary.
4. Read the net column, not the headline
A grant advertised at $200,000 is not $200,000 of spending money. Between flat 22% federal withholding, Social Security and Medicare, and state tax, a third or more disappears before the shares reach your account — and if your marginal bracket is above 22%, more is still owed at filing.
RSU vesting and tax FAQs
How are RSUs taxed when they vest?
Nothing is taxed at grant. On each vest date the full market value of the shares that release becomes ordinary compensation income, shows up on your W-2, and your employer withholds federal, Social Security, Medicare and state tax on it. Most companies cover the withholding by selling or holding back a slice of the shares, which is why a 100-share vest often lands as 60-something shares in your brokerage account.
Why is only 22% withheld instead of my real tax rate?
Vesting RSUs are supplemental wages, so most payroll systems use the flat supplemental rate: 22% on the first $1,000,000 of supplemental wages in a calendar year and 37% on everything above it. If your marginal bracket is 32% or 35%, that 22% is a down payment, not the bill. This calculator shows the withholding, so treat the gap between it and your bracket as money you will owe in April unless you send in an estimated payment.
What is my cost basis after the shares vest?
Your basis is the vest-date price, because that value was already taxed as income. Sell the same day and there is essentially no extra gain. Hold the shares and any further move is a capital gain or loss — short-term for the first year after vesting, long-term after that. Brokers have historically reported a $0 basis on these sales, so check the figure before you file or you will be taxed twice on the same dollars.
Does the projected share price predict anything?
No. The growth rate is a straight-line assumption that you choose, applied from today forward to each future vest date. Real share prices do not move in a straight line. Set growth to 0% to see the plan at today's price, then run a pessimistic and an optimistic number to see how wide the range really is.
What is a vesting cliff?
Many grants release nothing for the first 12 months, then drop 25% of the award in one lump at the one-year mark and trickle the rest out monthly or quarterly. That first lump is the cliff. Leave before it and you typically walk away with nothing, which is why the cliff date is worth knowing to the day when you are weighing a job change.
Does a big vest push me over the Social Security wage base?
It can, and that is good news for your take-home. Social Security is 6.2% only on wages up to the annual wage base. Once your salary plus vested RSU value passes it, the 6.2% stops for the rest of the calendar year, so later vests in the same year cost you less. Medicare's 1.45% has no cap, and an extra 0.9% Additional Medicare applies to wages above $200,000.