How much tax when RSUs vest, and is 22% enough?
See the federal tax a vest really adds on top of your pay, what your employer withholds, and the gap you may owe at filing.
Filing status
FEDERAL TAX GAP AT VESTUNDER-WITHHELD
$1,000
At these inputs, your employer withholds $11,000 of federal income tax on a $50,000 vest at the flat 22% supplemental rate. On top of $145,000 of pay the vest really adds $12,000 (24.0% of it, with the last dollar in the 24% bracket). That leaves $1,000 to pay when you file, unless you raise your withholding or make an estimated payment. Social Security and Medicare ($3,174) are withheld correctly.
Withheld
$11,000
Really owed
$12,000
Social Security + Medicare
$3,174
You keep
$34,826
UNDERSTAND YOUR RESULT
Where a vest goes
Of a $50,000 vest, $12,000 goes to federal income tax, $3,174 to Social Security and Medicare, leaving $34,826 (70%).
How far 22% falls short at different vest sizes
$25k
$500
$50k
$1k
$100k
$4k
$200k
$16k
$400k
$42k
$800k
$100k
On $145,000 of pay, withholding falls short of the tax owed by $500 on a $25,000 vest and $99,551 on a $800,000 one; yours is highlighted.
How the vest is taxed, bracket by bracket
| Bracket | Part of the vest | Tax |
|---|---|---|
| 24% | $50,000 | $12,000 |
The vest is taxed as the top slice of your single income: $50,000 at 24%, $12,000 in all.
What moves the needle
Each row re-runs the calculation with one change. Click to apply.How it's computed
FORMULA
Withheld = 22% × supplemental pay up to $1,000,000 in the year + 37% × the rest
Really owed = tax on (pay − 401(k) + vest − standard deduction) − tax on (pay − 401(k) − standard deduction)
Gap = really owed − withheld (positive: you owe it at filing)
Social Security and Medicare are withheld on the vest at the full rates, so they carry no gap
- The vest is ordinary income on the date it vests, at the share price that day, reported on your W-2 like salary. What you later gain or lose by selling is a separate capital gain or loss against that price.
- The vest is treated as the last income of the year, stacked on top of your pay, so it is taxed at the highest brackets your pay leaves. Other income, credits and deductions beyond the standard deduction and your 401(k) are not included.
- Federal income tax is computed with the 2026 brackets and the standard deduction for single filers. Your employer withholds at the flat supplemental rate whatever your bracket: 22% up to $1 million of supplemental pay in the year, 37% above.
- Social Security tax stops at $184,500 of wages in 2026; Medicare tax has no cap, and an extra 0.9% applies to wages above $200,000 (the threshold for the tax you owe is $250,000 for a joint return). Employers withhold all of these correctly.
- State income tax and local taxes are not modelled. The optional state rate only shows what a flat rate would take; states withhold on vests by their own rules.
WORKED EXAMPLE · SAMPLE NUMBERS
Withheld: 22% × $50,000 = $11,000. Really owed: taxable income of $140,650 before the standard deduction grows by $50,000, and the extra tax is $12,000 ($50,000 × 24%). Gap: $12,000 − $11,000 = $1,000. Social Security and Medicare on the vest: $3,174, withheld in full.
SOURCES
[1]Publication 15 (Circular E), Employer’s Tax Guide (2026), section 7: Supplemental WagesInternal Revenue Service[2]Rev. Proc. 2025-32: 2026 inflation-adjusted tax items (brackets, standard deduction)Internal Revenue Service, 2025[3]Topic no. 751, Social Security and Medicare withholding ratesInternal Revenue Service[4]Topic no. 560, Additional Medicare TaxInternal Revenue Service[5]Tax Withholding EstimatorInternal Revenue ServiceHSBuilt by Hussain Sehorewala · checked against worked examples · Sep 29, 2026
Keep this number honest as your life changes.
Put it on your Money Map and it re-runs as you change the seven numbers. It stays in this browser, and the calculator stays free.
Questions about this result
As ordinary income, at the share price on the vest date, reported on your W-2 and taxed like salary, with Social Security and Medicare tax too. If you later sell, the gain or loss is measured from that vest-date price.
Employers may withhold federal income tax on supplemental pay, which includes RSU vests and bonuses, at a flat rate instead of using your bracket. For 2026 that rate is 22%, and 37% on supplemental pay above $1 million in a year (IRS Publication 15).
It depends on your bracket. If the vest lands in the 24% bracket or higher, 22% is too little and the difference is due when you file; if your income is low enough that the vest is taxed at 12% or 22%, 22% is enough or more than enough. The bracket table above shows where your vest lands.
Yes, at the normal rates, and correctly. Social Security tax (6.2%) applies only up to $184,500 of wages in 2026; Medicare tax (1.45%) has no cap, and employers withhold an extra 0.9% on wages above $200,000.
Estimate the gap, as this page does, and cover it during the year: by raising your withholding on Form W-4 or making an estimated tax payment. The IRS Tax Withholding Estimator works out how much for your whole return. A tax professional can tell you what fits your situation.
No. State and local tax are not part of the federal gap. You can enter a flat state rate to see what it would take from a vest, but states withhold by their own rules.
THE LEDGER · 12 minThe Advanced 2026 Tax Strategies That Create Generational Wealth
THE LEDGER · 8 minWhy Generic AI Falls Short for Financial Advice - And How Specialized Knowledge Changes Everything