RSUPlanningDesk: RSU vesting tax calculator
for the withholding-vs-tax gap.
Free RSU calculator comparing withholding with estimated tax owed across vest, sale, and cash flow stages using explicit 2026 US tax assumptions.
Visible assumptions.
Inspectable calculations.
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Know what you are looking at. User-editable example assumptions. No live market quotes. Data details
Estimated tax minus modeled withholding
- 01At vest$50,000
Compensation value
200 units × $250 per share
- 02Payroll withholding$33,726
Value delivered after withholding
$16,274 withheld · 134.904 equivalent shares retained
- 03Tax reconciliation$26,833
Value after estimated tax
$23,167 estimated incremental tax; excludes later-sale tax
- 04Hypothetical later sale$38,866
Net sale proceeds
Sell retained shares at $300; $6,745 post-vest gain / loss
The later sale starts with retained shares. Its proceeds do not subtract the extra vest-tax reserve again. Review both amounts together.
Withholding is not the tax bill
2026 regular federal tax, simplified state/local assumptions, and employee payroll taxes.
| Tax component | Modeled withheld | Estimated incremental tax | Difference |
|---|---|---|---|
| Federal income tax | $11,000.00 | $16,713.25 | $5,713.25 |
| State + local | $4,000.00 | $5,000.00 | $1,000.00 |
| Social Security | $279.00 | $279.00 | $0.00 |
| Medicare | $725.00 | $725.00 | $0.00 |
| Additional Medicare | $270.00 | $450.00 | $180.00 |
| Total | $16,274.00 | $23,167.25 | $6,893.25 |
This estimate excludes AMT, credits, deduction interactions, multi-state sourcing, deferred-settlement RSUs, and multi-employer Social Security reconciliation. It is not a tax filing recommendation.
Shares after withholding
Fractional-equivalent estimate; employer rounding may differ.
Units retained after withholding
65.096 units withheldModeled net after estimated tax: $26,833
Later sale, separate tax event
Assumed sale at $300 per retained share.
| Item | Estimate |
|---|---|
| Post-vest gain / loss | $6,745 |
| Tax on positive gain | $1,605 |
| Net sale proceeds | $38,866 |
Losses receive no assumed tax benefit. The vest-date basis is not taxed again as a capital gain.
Multi-year vesting projection
Vesting tranches over the schedule
Assumes 8% annual price growth (a scenario assumption, not a forecast) and a fixed unit count split evenly across 4 years.
| Year | Units vesting | Price | Gross value | Withheld | Net value |
|---|---|---|---|---|---|
| 1 | 50 | $250.00 | $12,500 | $3,750 | $8,750 |
| 2 | 50 | $270.00 | $13,500 | $4,050 | $9,450 |
| 3 | 50 | $291.60 | $14,580 | $4,374 | $10,206 |
| 4 | 50 | $314.93 | $15,746 | $4,724 | $11,022 |
Sell at each vest vs. hold to the final year
Compares selling every tranche at vest against holding all retained shares to the last projected year, at the assumed capital gains rate.
| Strategy | Modeled net value |
|---|---|
| Sell at each vest | $39,428 |
| Hold to final year, then sell | $42,980 |
Holding is ahead by $3,552 in this modeled scenario. Price growth is an assumption, not a forecast; this is not investment advice.
Vest record log
Vest record log (saved on this device)
Keep a running record of vests for your own cost-basis tracking. Nothing leaves this browser.
No vest records saved yet.
Reconcile the shortfall before planning the sale
Withholding is a payment during the year. Estimated liability uses broader assumptions and should be checked against the applicable tax-year rules and a qualified adviser.
- 01Compare federal and state lines separately
- 02Check wage-base and supplemental assumptions
- 03Export the scenario with its tax year
This is the visible filtered page, not necessarily all dataset rows. Export CSV for the complete filtered results. Printed from RSUPlanningDesk.
Why withholding is only one line in the tax picture
Inputs: 200 units; vest price $250; single; taxable income before vest $230,000; state rate 10%; state withholding 8%; year-to-date wages $180,000; annual wages $250,000; supplemental wages $100,000; federal withholding 22%; sale price $300; long-term capital rate 23.8%. Gross vest value is 200 × $250 = $50,000 and federal withholding at 22% is $11,000. The estimate still depends on the tax year, jurisdiction, wages, deductions, and other income.
IRS Publication 15 (2026) Example checked September 12, 2026
Get more from the numbers.
Practical field guides, not a wall of jargon.
Good questions. Clear answers.
Does 22% withholding mean a 22% tax rate?
No. Withholding is a prepayment. The calculator estimates the regular federal tax increment separately.
Is this a complete tax return?
No. It excludes AMT, credits, deduction interactions, multi-state allocation, and other complexities.
Which tax year is supported?
2026, with source-linked federal brackets, wage base, and withholding rules. Future years require a rules update.
Useful, with the assumptions left in.
Every tool has a calculation methodology and visible source context. Synthetic examples are labeled, missing records stay missing, and no forecast is presented as certainty. Read the methodology or report a correction.