Why earning over £100,000 can reduce take-home pay
Earning above £100,000 can lead to outcomes that appear counter-intuitive, where additional income does not translate into a proportionate increase in take-home pay.
This is not the result of a single tax rate, but of multiple thresholds operating simultaneously.
How this arises
Above £100,000, entitlement to the Personal Allowance begins to reduce.
Depending on household circumstances, this may coincide with the withdrawal of other income-related entitlements. The combined effect can materially alter the effective impact of additional income.
Why headline tax rates are misleading
Headline income tax rates describe how individual slices of income are taxed.
They do not show:
how allowance withdrawal affects taxable income
how entitlement loss compounds the effect
how different rules overlap as income increases
As a result, the true marginal impact is often obscured.
Understanding the position in context
Understanding whether additional income improves or worsens the overall position requires looking at the combined effect of thresholds and withdrawals, rather than any single rule in isolation.
Further analysis
A personalised written analysis can show how this applies in practice, using your information and circumstances.
View the £100k Cliff Edge Report
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