Your vest confirmation shows gross shares, a withholding rate, and fewer net shares deposited — or your pay stub withholding looks nothing like the share count you expected. You want the math connecting tax withheld at vest to the shares that actually land in your account.
Start here
What you need before using this
- confirmation with gross shares, , method, and net shares.
- Pay stub for period showing federal, state, and FICA .
- Brokerage deposit showing share count received.
- trade confirm if shares sold on day.
- tax or calculator output for comparison.
Plan settlement methods and rounding rules vary. Confirm net share counts on your vest confirmation and brokerage statement.
Why this happens
delivery is a taxable wage event at . Payroll must income and payroll taxes like other compensation.
sells enough shares at market price to cover estimated — net shares = gross minus shares sold.
Net settlement withholds shares directly without a market sale — net shares = gross minus shares retained for tax.
percentage on confirmation (e.g., 22% federal supplemental) applies to , not to net shares only.
FICA also reduces net shares when includes Social Security and Medicare.
State may use flat supplemental rates or tables — net share count reflects combined federal, FICA, and state.
Share price at sets both wage and proceeds — volatile -day prices change net shares.
Rounding and plan rules may leave fractional shares as cash or round down net shares — check plan document.
Multiple vests in one month may combine on one confirmation with one net share total.
Higher supplemental election — if your plan allows — increases shares sold and lowers net shares.
Under- at supplemental rates means net shares look generous but year-end tax bill may be larger.
Net shares in brokerage are post- delivery — you already owe wage tax on full even if you never sell.
at applies to sales; basis for those shares is generally already on .
Pay stub cash may differ from share-based when runs with salary on same check.
Refresh grants on same schedule use the same net share mechanics as initial grants.
What to check
- Gross shares × = wage amount on confirmation.
- Shares sold or withheld vs net shares math on confirmation.
- Federal rate vs IRS Pub. 15 supplemental options.
- FICA lines on pay stub for period.
- State if applicable.
- Brokerage deposit share count matches confirmation net shares.
- price vs used for wages — small differences normal.
- gap estimate vs supplemental rate for full-year tax.
Thinking net shares mean only the gain is taxable later
What to check in your documents
- confirmation gross, , net share lines.
- Pay stub supplemental for .
- Brokerage deposit notification.
- trade confirm with shares and proceeds.
- Year-end Box 1 vs sum of .
100 gross shares at $50 with 22% federal supplemental
Illustration only, not your tax situation.
Questions people ask
- How are net RSU shares calculated?
- Generally gross shares minus shares sold or withheld for tax at . Exact formula is on your confirmation and plan rules.
- Does 22% withholding mean I keep 78% of shares?
- Not exactly — FICA and state also consume shares. Total share reduction often exceeds 22%.
- Why did I get fewer net shares than my colleague?
- Different grant sizes, , W-4 elections, state rates, or supplemental elections change net shares.
- Net settlement vs sell-to-cover — same net shares?
- Similar net share counts possible, but creates a brokerage sale; net settlement may not. Tax wage amount is the same .
- Can I elect more withholding for more net shares later?
- Some plans allow higher flat supplemental rates up front, selling more shares at to reduce year-end gap — check plan admin.
- Net shares and cost basis?
- Basis per share is generally — applies to net shares you hold. See calculation guide.
- Withholding on net shares only?
- No — applies to full wages, funded by selling or from gross shares.
- Pay stub vs confirmation net shares?
- Confirmation shows share math; pay stub shows cash wages and . Both should tie to same .
- What if net shares are zero?
- Rare — can happen when exceeds entire on small grants or high elected rates. Confirm with plan admin.
- Which calculators help?
- , net proceeds, tax, and gap calculators model shares sold and cash tax.
When to get help from a tax pro
- Net shares do not match confirmation formula.
- rate on confirmation differs from pay stub without explanation.
- Large with zero FICA on confirmation despite below wage base.
- Multi-state on net share delivery.
Related calculators
- RSU Sell-to-Cover Calculator
Model sell-to-cover mechanics — shares sold for withholding, shares delivered net, and cash you may still need.
- RSU Net Proceeds Calculator
See estimated net shares and cash after taxes and withholding — useful for budgeting around vest dates.
- RSU Withholding Gap Calculator
Focus on the gap between what your employer withholds on RSU vests and what you may owe when everything is reconciled.
- RSU Tax Calculator
Model federal and state taxes on your RSU vest, compare withholding to estimated tax, and see what you may keep.
Related pages
- RSU Net Settlement Explained
Net settlement uses withheld shares to pay vest tax — wage income is still full vest FMV, unlike sell-to-cover which often generates a 1099-B sale.
- Sell-to-Cover Shares Explained
Sell-to-cover is your employer selling part of your vest to pay withholding — you receive the rest.
- Reading Your Pay Stub After an RSU Vest
Vest FMV adds to gross wages on the same pay stub as salary — supplemental withholding and FICA lines spike, but net pay alone does not prove your full-year tax is covered.
- Why Was My RSU Withholding Only 22%?
Employers commonly use flat supplemental rates on RSU vests. Your actual tax can be higher if you are in a higher bracket.
- How to Read an RSU Vest Confirmation
Vest confirmation FMV is your wage income and future sale basis — save the PDF even when net shares look smaller after withholding.
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.
RSU vest as ordinary wage income on Form W-2 and separate capital-gain treatment on later sale.
- IRS — U.S. taxation of stock-based compensation (RSU vesting and W-2 reporting)
Internal Revenue Service · Official
Describes RSU income at vest, W-2 reporting in boxes 1/3/5, and ordinary income treatment.
- IRS Publication 525 — Taxable and Nontaxable Income
Internal Revenue Service · Official
Covers compensation income from stock-based pay, including restricted property under section 83.
- Equity Compensation — RSU taxation at vest and on sale
Charles Schwab (Workplace Financial Services) · Brokerage explainer
Plain-language explainer: RSU value at vest on W-2, FICA, withholding may not cover full tax, separate capital gains on sale.
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.