vestingtax.com
RSU tax calculator

RSU tax rate: what marginal rate applies to your vest?

RSU vest income stacks on salary — your marginal rate on that vest slice may be higher than flat withholding.

Rates and rules change. Content is reviewed for tax year 2026. Check the last-reviewed date and methodology on each page, then confirm against IRS or state guidance before you file.

Spot an outdated rate or date?

We update when we can, but we miss things. Send a link to the official source if you have one.

Email us

Your vest notice shows a flat withholding rate and you want the rate that actually applies to the vest dollars — your marginal bracket on stacked income — not the supplemental payroll percentage on the pay stub.

In plain terms

The tax rate that matters for planning is usually your on stacked income — federal, state, and payroll taxes on the slice sitting above your salary. Employer supplemental (often 22% federal on the income-tax portion) is a payroll rate, not your final .

Gather before you start

  • Expected value this year.
  • Salary, bonus, and other wage income.
  • Filing status and state of residence.
  • rate shown on confirmation or pay stub.

How the tax works

Federal income tax uses progressive brackets. The dollars from an usually stack on top of salary, bonus, and earlier vests in the same calendar year. The tax rate on that last slice — your — can be higher than the average rate on your full income, especially when a single pushes you into the next bracket.

Payroll on vests often follows IRS Pub. 15 rules: a flat rate on the equity portion (commonly 22% federal for income tax when annual wages exceed the threshold). That flat rate is what your employer sends to the IRS as prepayment; it is not a statutory tax rate and may be lower than your true marginal bracket.

Payroll taxes add on top of income tax. Social Security applies until you hit the annual wage base; Medicare and Additional Medicare Tax apply to high wage income including . If salary already consumed the Social Security cap, the may face Medicare only on the FICA slice — but federal and state income tax still apply to the full amount.

State income tax, where it applies, has its own progressive brackets or flat rates on wages. California, New York, and other states can add a meaningful marginal layer on the same dollars already subject to federal tax and FICA.

Your final effective rate on the is determined on Form 1040 after deductions, credits, and full-year income — not on the pay stub alone. Comparing supplemental to estimated marginal tax is how you decide whether to increase W-4 or make estimated payments.

What to check on your end

  • Estimated total taxable income including the .
  • Federal marginal bracket for the top slice of income.
  • State if your state taxes wages.
  • Flat supplemental rate vs. estimated .
  • Whether you already hit the Social Security wage base before the .

Using the RSU withholding rate as your RSU tax rate

The rate on your notice is what payroll withheld — not necessarily what the costs you in tax when salary, bonus, and other vests stack in the same year.

What to pull from your files

  • confirmation rate.
  • Pay stub after .
  • Prior-year return for bracket context.
  • W-4 and any extra elections.

Example scenario (hypothetical)

Illustration only, not your tax situation.

Example: Chris earns $190,000 salary and vests $40,000 of . Federal supplemental might use a flat rate on the , but the $40,000 may sit entirely in a higher marginal bracket. Chris uses the tax calculator and gap tool to compare rates before filing.

Questions people ask

What is the RSU tax rate?
There is no single tax rate — it depends on your total income, filing status, and state. The rate on the slice is your , often higher than flat supplemental .
Is the RSU withholding rate my final tax rate?
Usually not. is a payroll estimate. Your final rate depends on your full-year return, deductions, and credits.
What RSU tax rate does California use?
California taxes income as ordinary wages with progressive state brackets — not a special rate. See the California tax guide for SDI, FTB sourcing, and state gaps.
Which calculator shows my RSU tax rate?
The tax calculator estimates tax on a ; the gap calculator compares supplemental to estimated liability. Neither is a filing position.
Does timing multiple vests change my marginal rate?
Yes. Two vests in one year stack into the same brackets. Spreading vests across years can change which bracket the equity dollars land in — a planning question, not something payroll adjusts automatically.

When a CPA is worth it

  • You are near a bracket boundary and timing vests matters.
  • You have multi-state wages from .
  • You want precise modeling with itemized deductions.
  • NIIT or additional Medicare tax may apply.

Sources and notes

Primary tax claims on this page are supported by the official and secondary sources below. Broker and software links describe reporting mechanics — confirm rules against IRS or state guidance.

Marginal vs supplemental withholding rates on RSU vest income.

Related calculators

Related pages

For learning, not filing

VestingTax.com is not a CPA firm or tax preparer. Grants, employers, and states all differ. Use the cited IRS and state sources above, your own documents, and a qualified tax professional before you make decisions from this guide.

Editorial standardsDisclaimer