Your vest withheld 22%. Your bracket is not 22%.
Most U.S. employers withhold federal income tax on RSU vests at the flat supplemental rate (commonly 22% under the $1M threshold). If your ordinary marginal rate is 32% or 35% — and you add California 10.23% or New York 11.7% — April is not a surprise; it is arithmetic.
What competing “RSU calculators” often skip
- State supplemental rates as a first-class input — we publish a 50-state table and wire it into tools.
- Gap framing — dollars short of your marginal rate, not only a single “tax due” blob.
- Operational next steps — sell-to-cover share count, quarterly estimate sketch, holding-period day count.
We are not your CPA. Formulas are on the page so you can argue with them.
Open a tool
- Withholding gap — vest value × (marginal − 22%)
- RSU tax sketch — federal + state flat rates
- Sell-to-cover shares — cash need ÷ price
- Bonus take-home — supplemental stack
- State rate table