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Lucro calculators

The £100,000 tax trap calculator

See what each pay increase could add to your take-home pay, how the Personal Allowance taper affects you, and the common ways people reduce adjusted net income.

For employees and business owners

Where does the extra pay go?

Move your income and the figures update straight away. The comparison uses annual PAYE estimates.

2026/27 tax year
A person reviewing financial figures
Annual gross employment income
£
Where you pay Income Tax
Try a different income
£80,000£100,000£125,140£180,000
Your positionInside the taper
Below £100kAllowance tapersAllowance gone

What are you already doing?

Add annual amounts. Each route is calculated differently, so only enter contributions that match the descriptions below.

Clear all

Salary exchanged for pension

Gross salary given up before Income Tax and employee National Insurance.

£
Use this route to close the gap

Workplace pension, net pay

Enter the gross amount deducted from pay before Income Tax. Employee National Insurance is still worked out on pay before this deduction.

£
Use this route to close the gap

Personal pension, relief at source

Enter what leaves your bank. The calculator adds basic-rate relief, so £800 becomes £1,000 gross.

£
Use this route to close the gap

Gift Aid donations

Enter what you donated. A qualifying £800 donation is treated as £1,000 gross for adjusted net income.

£
Use this route to close the gap
Total reduction to adjusted net income£0
Reduction needed to reach £100,000£10,000

Pension allowance check. The gross pension amounts entered exceed the standard £60,000 annual allowance. Tapering, carry forward and individual circumstances can change the amount available.

What each pay step changes

This is the bit payslips often make hard to see. Each row compares that salary with the previous £1,000.

Swipe the table sideways to see every column.

Gross incomeCash left after entriesExtra grossExtra netKept from £1Income Tax + NI

What could reducing adjusted net income change?

Compare four common routes using the remaining gap in your current figures. This explains the mechanics, not what you should do.

Illustrative salary sacrifice route

Reduce adjusted net income by £10,000

That could restore your full Personal Allowance. Whether salary sacrifice or a personal contribution is available depends on your employer and pension.

Salary exchanged£0
Estimated take-home cost£0
Allowance restored£0
Effective relief shown0%

Compare the routes

Same income reduction, different result

The figures below use the amount needed to bring adjusted net income back to £100,000.

Salary sacrifice

Can reduce taxable salary and employee National Insurance where your employer offers it.

Workplace pension

A net pay contribution is deducted before Income Tax, but normally not before employee National Insurance.

Personal pension

The amount you pay is topped up by basic-rate tax relief. You may need to claim further relief.

Gift Aid

The charity receives the basic-rate uplift. It is a donation, so the money does not remain yours.

Illustration only. Tax rates and thresholds can change. This is not a penny-perfect payslip, tax return, financial advice or tax advice. The cash figure assumes any higher-rate pension or Gift Aid relief shown has been claimed, even though it may not arrive through the same payslip. It assumes standard PAYE arrangements and National Insurance category A. It does not model student loans, Child Benefit charges, benefits, tax-code adjustments, dividend rates or every pension rule. Workplace pension schemes can use salary sacrifice, net pay or relief at source, and you should check which method your scheme uses. Pension tax relief is limited by earnings, annual allowance rules and individual circumstances. Gift Aid requires sufficient UK Income Tax or Capital Gains Tax to have been paid. Scotland has different Income Tax bands, which the region selector estimates separately.
Rules used: HMRC Income Tax rates, HMRC adjusted net income guidance, HMRC workplace pension guidance, HMRC pension tax relief guidance, HMRC Gift Aid guidance, and HMRC 2026/27 payroll rates.
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