← Calculators/Tax year 2026/27·Last reviewed
The £100k / 60% tax trap calculator
Set a target adjusted net income; the tool illustrates the pension contribution that reaches it and shows the modelled tax and support effects side by side.
Free, no sign-up. Runs the same engine and versioned tax-year config as the signed-in suite — the pension and bond calculation workbench UK paraplanners use to produce compliance-annex PDFs. Your calculator figures stay in this browser unless you choose to share or rerun them in the signed-in workbench. How we verify the numbers.
— In short
The “£100k tax trap” is the band of income between £100,000 and £125,140 where the personal allowance is withdrawn at £1 for every £2 earned — an effective marginal rate of 60% for rUK non-savings income (67.5% in Scotland). Above £100,000 you can also fail the income test for Tax-Free Childcare and, in England, working-parent funded hours. A pension contribution can reduce adjusted net income; the tool uses only a childcare amount you enter and does not confirm the other eligibility conditions. It illustrates the result rather than recommending a contribution.
ParaplanAI calculator illustration
Tax Trap
Tax year 2026/27 · Last reviewed 20 Jul 2026
More income types
Taxable profit from a trade, profession or partnership.
Rental profit after allowable expenses.
Any other income taxed as non-savings (e.g. pension income, trust income).
Grossed up automatically (÷ 0.8). Lowers your adjusted net income — and the contribution needed.
The amount already being made this tax year using the selected method. The result shows the additional contribution needed. If existing contributions use mixed methods, model them separately before relying on the tax split.
Enter the known individual ANI, including £0. This also tests the childcare cliff when selected.
Additional illustrated contribution
£18,000 into your pension for £7,200 out of pocket
60% effective relief. For every £1 it costs you, £2.50 is illustrated as reaching the pension after the modelled tax and benefit effects.
At this ANI, the illustrative earned-income curve is 62%. It assumes the income movement is employment earnings and smooths HICBC across its statutory steps.
| Position | As you are now | With £18,000 in |
|---|---|---|
| Adjusted net income | £118,000 | £100,000 |
| Personal allowance | £3,570 | £12,570 |
| Income tax | £38,232 | £31,032 |
| Employee NI (Class 1 only) | £4,371 | £4,371 |
| Child Benefit clawed back | £2,382 | £2,382 |
| Childcare support | £0 | £0 |
| Net tax and retained-support position | £42,602 | £35,402 |
About this calculation
Annual-allowance headroom currently uses the standard £60,000 with no taper, MPAA or carry forward. Confirm the available headroom in the annual allowance calculator before treating the illustrated contribution as feasible.
ITA 2007 s.35 · ITEPA 2003 s.681B–681H
For planning and illustration purposes only. Verify all inputs against source documents. This tool does not constitute financial or tax advice.
Print this quick illustration now. Signed-in users can add a client or file reference before saving it as a PDF — the branded compliance annex, with the full working and HMRC references on every page, comes from the signed-in workflow.
Keep the working
Save this as a branded compliance annex PDF.
A free account saves this calculation to a client record and renders the annex — 3 a month, no card.
Need an exact annual-allowance headroom with taper and carry-forward? The pension workbench computes the full AA position across schemes.
— How it's calculated
Adjusted net income — what counts
Adjusted net income is your total taxable income (salary, bonus, taxable benefits in kind, self-employment, property, dividends and savings) less grossed-up Gift Aid and grossed-up relief-at-source pension contributions. It is the figure that drives the personal-allowance taper, the High Income Child Benefit Charge and the £100,000 childcare cliff — and it is what a pension contribution reduces, £1 for every £1 of gross contribution.
ITA 2007 s.58 (adjusted net income) · s.35 (personal-allowance taper)
The illustrated contribution to the target
From your target adjusted net income the tool solves for the additional gross pension contribution after the existing contribution you enter. It then illustrates the immediate cash cost net of the modelled tax and support effects. Relief at source, net pay and salary sacrifice can produce different tax results where taxable income is low, income is mixed or the contribution exceeds taxable pay. Salary sacrifice can also reduce employee National Insurance, subject to eligible pay, employer scheme rules and the National Minimum Wage floor. The net cost subtracts only the incremental modelled relief and any user-entered childcare support restored by the ANI test.
FA 2004 s.188–192 (pension tax relief) · SSCBA 1992 s.8 (employee NI)
Child benefit and the £100k childcare cliff
From 2024/25, between £60,000 and £80,000 the High Income Child Benefit Charge claws back 1% of Child Benefit for every £200 of adjusted net income above £60,000, rounded down to a whole percentage; at £80,000 the charge percentage reaches 100%, while £60,000 or below removes it. The £100,000 childcare income test is separate. Enter only the annual support genuinely at risk under that test—actual Tax-Free Childcare top-up plus any income-tested working-parent hours value. The tool does not assume maximum caps and does not include universal hours.
ITEPA 2003 s.681B–681H (HICBC) · gov.uk/tax-free-childcare · DfE early-years funding rates
— How to illustrate a pension contribution against the £100k tax trap
Step 1
Work out your adjusted net income
Add up your taxable income, then deduct grossed-up Gift Aid and any relief-at-source pension you already pay.
Step 2
Pick a target
Choose the adjusted net income you want to reach — £100,000 restores the full personal allowance and can satisfy the childcare income test; £60,000 or below removes post-2024/25 HICBC.
Step 3
Review the illustrated contribution
Enter pension contributions already being made. The tool then solves for the additional gross contribution that brings adjusted net income to the target.
Step 4
See the net cost
The net cost is the gross contribution less income-tax relief, any NI saving and any child benefit or childcare regained.
Step 5
Check the annual allowance
Confirm annual allowance, taper, MPAA, carry-forward, relevant earnings, access and employer feasibility before implementation.
— Worked example
- Required gross pension contribution
- £18,000
- What it actually costs you (net)
- £7,200
- Personal allowance restored
- £3,570 → £12,570
- Income tax
- £38,232 → £31,032
- Effective relief on the contribution
- 60%
Computed live by the same engine the tool above runs. At a £100,000 target the personal allowance is fully restored. HICBC starts to reduce only below £80,000 and is removed at £60,000 or below under the post-2024/25 rules.
— Frequently asked questions
What is the £100k tax trap?
Between £100,000 and £125,140 of adjusted net income, the personal allowance is withdrawn at £1 for every £2 earned. That withdrawal, on top of the 40% higher rate, gives an effective marginal rate of 60% on that band (45% plus the withdrawal gives 67.5% in Scotland). You also lose Tax-Free Childcare and the funded hours over £100,000.
How much pension contribution do I need to avoid it?
A gross pension contribution reduces adjusted net income £1 for £1. The additional amount is starting adjusted net income after existing contributions minus the target. From £118,000 with no existing contribution to £100,000, for example, the additional gross amount is £18,000.
Is salary sacrifice cheaper than a personal pension?
Not always. Salary sacrifice can reduce employee National Insurance, but the income-tax result can differ from relief at source or net pay where income is mixed, taxable income is low or contributions exceed taxable pay. Employer rules and the National Minimum Wage floor also apply.
Does the Scottish tax trap differ?
Yes. The personal-allowance withdrawal still applies, but on top of the Scottish advanced rate of 45% it produces an effective marginal rate of about 67.5% between £100,000 and £125,140 — switch the residence toggle to Scotland to see it.
What childcare do I lose over £100,000?
If either parent’s adjusted net income is over £100,000, the household fails the income test for Tax-Free Childcare and, in England, working-parent funded hours. Universal hours are separate, and age, work, residence, provider and account rules still apply. The tool includes only an annual support amount you enter yourself.
— Related
- Income tax traps: the complete guide
- Pension annual allowance calculator — check the contribution fits
- Tapered annual allowance calculator — for high earners
- Income tax calculator — reconciled rUK and Scottish bands
- The £100k / 60% tax trap, explained — the rule behind the numbers
- The Scottish 67.5% tax trap, explained
- How every figure is verified against official sources
— When you're ready
Put this calculation in the client file.
ParaplanAI is the paraplanner's calculation workbench: the same engine as this free tool, plus document extraction, full multi-event workflows, and a branded compliance annex PDF with the step-by-step working and its HMRC references — the file a compliance officer signs.