100k tax trap calculator
rates verified 24 Jul 2026 · next refresh after Autumn Statement
Direct answer
Enter a salary between £100,000 and £125,140 in the homepage resolver. The marginal-rate line reads 62%. The personal allowance shrinks £1 per £2 over £100,000, surfacing extra taxable income at 40%5. A pension salary sacrifice equal to the excess over £100,000 restores the full allowance.
What the calculator does
- Reads salary and computes the tapered personal allowance.
- Recomputes income tax with the smaller allowance.
- Compares against the same salary with a salary sacrifice that brings adjusted net income back to £100,000.
- Shows the marginal rate on the next £1,000 of pay rise.
For £125,140 of gross salary, a £25,140 sacrifice into pension saves £5,028 in restored personal allowance plus the underlying 40% on the sacrificed amount.