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Estimated after-tax proceeds on shares sold
£0
Waiting for an employee-shares tax read.
What this means
The first tax event is usually employment income at vest or exercise. Only the movement after that point normally becomes CGT territory.
Professional read
The tool treats the market value at vest or exercise as the amount already brought into employment income, which then becomes the base cost for later CGT work.
Taxing the full sale proceeds as CGT and forgetting the PAYE-style income tax event that often happened earlier at vest or exercise.
Check whether your award is actually a tax-advantaged scheme before relying on this, and reconcile the broker statement with the payroll withholding your employer has already applied.
EMI, CSOP, SAYE, SIP, foreign tax, mobile employee issues, or employer withholding quirks need a case-specific review.
Methodology and source basis
This tool follows the usual UK sequence for non-tax-advantaged employee shares: employment income first, then CGT only on later movement from the vest or exercise value to the eventual sale value. It uses the 2026/27 rest-of-UK income tax bands, employee NIC rates, the £3,000 annual exempt amount, and 18% / 24% CGT rates for shares.
| Reference | Why it matters |
|---|---|
| GOV.UK employee share schemes | Confirms the core difference between tax-advantaged and non-tax-advantaged employee share routes. |
| GOV.UK tax when you sell shares | Sets the CGT treatment on disposal once you have already established your base cost. |
| HMRC 2026/27 rates and thresholds | Source for the income tax and employee NIC assumptions used for the PAYE-style estimate. |
Worked examples — see the math on real numbers
How RSU (Restricted Stock Unit) vests and stock options are taxed at vest + sale, with CGT implications.
Lisa — Big Tech engineer, RSU vest in 2026/27
| Salary | £90,000 |
| RSU grant value at vest | £40,000 |
| Shares vested | 500 shares @ £80 |
| Sell-to-cover (employer) | ~40% withheld = 200 shares |
| Shares received net | 300 shares |
| Sale price 6 months later | £90/share |
The math:
- RSU vest treated as employment income: £40,000 taxable as salary
- Combined income: £90,000 + £40,000 = £130,000 (enters additional-rate territory)
- Sell-to-cover handles the income tax + NI at vest (~40%+ depending on band)
- Remaining 300 shares have a cost basis of £80 (the vest price)
- Sale at £90: gain per share = £10 → total gain £3,000
- CGT allowance £3,000 fully uses this — no CGT due
Result: Lisa keeps the full £27,000 sale proceeds (£90 × 300 shares) because the gain matches her CGT allowance. If she'd sold a year later at £100, the additional £3,000 gain would be taxable at 24% higher-rate CGT = £720.
Mark — exec with NSO stock options
| Salary | £75,000 |
| NSO grant | 1,000 options at £40 strike |
| Exercise price (FMV at exercise) | £70 |
| Sale price 14 months later | £95 |
The math:
- At exercise: spread = £70 − £40 = £30 × 1,000 = £30,000 taxable as employment income
- Combined income £105,000 enters 60% trap territory — partial PA taper applies
- Income tax + NI at exercise: ~£15,300
- Cost basis for CGT: £70 per share (FMV at exercise)
- On sale: gain per share £95 − £70 = £25, total £25,000
- After £3,000 CGT allowance: £22,000 taxable
- CGT at higher-rate: 24% × £22,000 = £5,280
Result: Mark's total tax across exercise + sale is ~£20,580 on what was nominally a £55,000 windfall (£95 × 1,000 − £40,000 cost). Holding 12+ months past exercise unlocked the lower 24% CGT rate vs the 60%+ marginal rate if he'd exercised-and-immediately-sold.
Figures use 2026/27 UK tax-year rates and thresholds. Always verify against your specific payslip or tax statement before acting.
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