UK £100k Tax Trap Calculator
See how the UK £100,000 Personal Allowance taper creates a ~60% effective tax rate, and exactly how much pension contribution clears the trap and restores your allowance.
What is the £100k tax trap?
Quick answer: In the UK, earning between £100,000 and £125,140 triggers a hidden tax trap: your £12,570 tax-free Personal Allowance is withdrawn £1 for every £2 over £100,000, creating an effective marginal tax rate of about 62% (60% income tax plus National Insurance). At £110,000 you lose £5,000 of allowance; a £10,000 pension contribution brings you back to £100,000 and restores it. Enter your salary below to see your position. See methodology →
Default inflation rate for United Kingdom: 3.0% per year, based on UK Office for National Statistics (CPI) data (2026). You can override it in each calculator’s advanced options. See data sources for full citations.
How We Work It Out
Between £100,000 and £125,140 of adjusted net income:
The allowance is fully withdrawn at £125,140, after which the marginal rate falls back to the 45% additional rate. Figures: England/Wales/NI, 2024/25 onward, per GOV.UK.
Real-World Examples
£110,000 salary in the trap
On £110,000 you've lost £5,000 of your £12,570 Personal Allowance, leaving £7,570. Your next pound is taxed at an effective 62%. A £10,000 pension contribution pulls your adjusted net income back to £100,000, restores the full £12,570 allowance, and makes that contribution remarkably tax-efficient.
Frequently Asked Questions (FAQ)
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