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How much will you owe when your RSUs vest?

RSU vesting creates ordinary income at the full fair market value on vesting day. The 22% supplemental withholding rate your employer uses is almost always less than what high earners actually owe, sometimes by tens of thousands of dollars. See your number before April finds it for you.

2026 estimates · Federal + California · Not tax advice

RSU tax impact calculator

See the gap between what’s withheld and what you actually owe.

When RSUs vest, the shares’ value is ordinary income. Employer withholding at the 22% supplemental rate often falls well short of the actual tax owed, especially for high earners in the 32–37% bracket. Enter your numbers to see your shortfall before it becomes an April surprise.

Your vesting event

Filing status
State

California adds 13.3% on top of federal tax

Employer supplemental withholding rate

22% default; 37% applies above $1M in supplemental income

Your RSU tax picture

Gross income recognized at vesting$50,000
Federal income tax on vesting income$15,016
California tax (13.3%)$6,650
Total tax owed on vesting$21,666
Estimated employer withholding$11,000

Tax shortfall

$10,666

This is the estimated amount you’ll owe beyond what was withheld. You may need to make a quarterly estimated payment to avoid an underpayment penalty.

Shortfall exceeds $1,000 — underpayment penalty may apply

The IRS charges an underpayment penalty when you owe more than $1,000 and haven’t covered it through withholding or estimated payments. Consider making a quarterly estimated payment for the quarter in which the RSUs vested.

Use the quarterly estimate planner

If you hold shares after vesting

The FMV on your vesting date becomes your cost basis. Any appreciation after that date is a capital gain: short-term (taxed as ordinary income) if you sell within one year, long-term (0%, 15%, or 20% rates) if you hold for more than one year. This calculator covers only the ordinary income recognized at vesting.

RSU and stock option tax planning →

If your CPA and financial advisor aren’t coordinating on when to sell, how to offset gains, and how vesting events affect your estimated payments, that’s a gap that tends to cost real money.

Illustrative estimates only. Uses 2026 federal income tax brackets and standard deductions. California rate modeled at 13.3% flat on vesting income. Does not model NIIT, AMT, state deductions, itemized deductions, or tax credits. Does not constitute tax advice. See full disclaimer.

Work with Matt

Ready to build a plan?

Matt Reese, CPA coordinates RSU vesting events, estimated payments, and post-vesting holding decisions alongside your financial advisor, so the withholding gap doesn't become a surprise.

Tax services provided through Matt Reese, CPA. This page is educational and does not constitute tax or investment advice.