The GBP 100k tax trap refers to the loss of personal allowance as income rises above £100,000, increasing the effective marginal tax rate.
The GBP 100k tax trap is shorthand for the Personal Allowance taper. In 2026/27, adjusted net income above £100,000 can reduce the Personal Allowance, which makes the effective tax rate on that slice of income higher than the headline higher-rate band.
On £35,000 a year with a standard 2026/27 tax code, no pension, no student loan, the figures work out like this. Open a calculator to put your own numbers in.
The taper is based on adjusted net income, not simply take-home pay. The exact effect depends on the tax-year rules and the deductions or reliefs that apply.
| Adjusted net income example | £100,000 | Example value shown in this threshold guide. |
|---|---|---|
| Taper starts | £100,000 | Personal Allowance can begin reducing above this adjusted net income level. |
| Allowance fully removed | £125,140 | The standard Personal Allowance can be fully removed by this adjusted net income level. |
This visual is a threshold guide, not tax advice. Use the tax-trap calculator to model an estimate with your chosen assumptions.
| Tax/source year | 2026/27 |
|---|---|
| Region | England/Wales/Northern Ireland |
| Tax code basis | 1257L where the page uses PAYE defaults |
| Pension basis | No pension deduction unless this example says otherwise |
| Student loan basis | No student loan unless selected in this example |
| Calculator setting | The answer is more useful when matched to the same tax year, region, tax code, pension and loan settings used in the calculator. |
|---|---|
| Records to compare | Payslips, HMRC records, student-loan notices and pension scheme documents can explain differences. |
| Tax code | HMRC tax-code changes, K codes, BR/D codes, or emergency markers can change PAYE deductions. |
|---|---|
| Cumulative basis | Week 1, Month 1 or non-cumulative payroll can differ from a smooth annual calculator estimate. |
| Pension method | Relief at source, net pay and salary sacrifice can affect taxable pay and take-home pay differently. |
| Payroll timing | Bonus, overtime, arrears, refunds, cut-off dates and corrections can all move a single payslip. |
| Open the salary calculator with editable assumptions | calculator next step |
|---|---|
| Review calculation sources and methodology | source context |
| What is not decided here | PayBreakdown does not decide payroll correctness, lender approval, benefit entitlement or employer compliance, and does not give regulated financial, mortgage, debt, tax, payroll or legal advice. |
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The figures on this page are worked from GBP 100k tax trap, using the values below. Open the calculator if your example salary differs.
The taper removes part of the tax-free Personal Allowance as adjusted net income rises. That can mean extra income is taxed directly and also causes more existing income to become taxable.
Use the page as a planning explanation, then check official records or professional advice where a tax return, benefit decision or employer scheme decision depends on the result.
This is educational guidance on how UK pay and tax work. It does not decide payroll correctness, HMRC treatment, lender approval, benefit entitlement or employment rights, and it is not regulated financial advice. Where a figure matters, check it against your payslip, your HMRC account, or the official guidance linked above.
It is based on adjusted net income. Gross salary is a starting point, but pension treatment, benefits and other income can change the figure.
No. Pension can affect adjusted net income, but the right treatment depends on the scheme method, payroll rules, contribution limits and personal circumstances.
No. It explains the calculation concept and links to modelling tools and official sources.
Last updated 2026-08-27. Checked by Sean Elsmore. Rates last checked against GOV.UK on 2026-08-07. Estimates are for planning and should be checked against official records where the decision matters.