The UK 60% Tax Trap, and What It Means for US Citizens

Between £100,000 and £125,140 of adjusted net income, the UK withdraws your Personal Allowance at £1 for every £2 of income, producing an effective marginal tax rate of about 60% on that slice — 62% once employee National Insurance is counted. The standard British fix is to push adjusted net income back below £100,000 with a pension contribution or a Gift Aid donation. For a US citizen or green card holder it is not that simple: cutting UK tax also cuts the foreign tax credit that shelters your US liability, so the saving has to be measured on both returns before you act.

Key takeaways

• The Personal Allowance falls by £1 for every £2 of adjusted net income above £100,000 and reaches nil at £125,140. Across that band each extra pound of salary costs roughly 60p of income tax.
• The trap is driven by adjusted net income, not gross pay. Gross pension contributions, grossed-up Gift Aid donations and salary sacrifice all reduce it — by three different mechanics.
• The High Income Child Benefit Charge is a separate trap between £60,000 and £80,000. By £100,000 your Child Benefit has already been clawed back in full, so the two charges do not overlap.
• For a US person, a UK pension contribution can reduce US taxable income under Article 18(5) of the US–UK treaty — but only where specific conditions are met, and it always reduces creditable UK tax.
• Gift Aid is the harder case: it cuts your UK tax, and therefore your US credit, while generally giving you no US deduction in exchange.

Rates and thresholds in this article are as at 1 October 2026 and apply to the 2026-27 UK tax year for taxpayers in England, Wales and Northern Ireland. Scotland sets its own income tax rates and bands, although the Personal Allowance and its £100,000 taper are UK-wide. The Budget is scheduled for 28 October 2026 and could change any of these figures, so confirm them before acting.

What the 60% trap actually is

There is no 60% rate in UK tax law. The headline rates for 2026-27 are 20% on the first £37,700 of taxable income, 40% up to £125,140 and 45% above that. The 60% is an artefact of how the Personal Allowance is taken away.

Everyone starts with a Personal Allowance of £12,570. HMRC's rule is blunt: "Your personal allowance goes down by £1 for every £2 that your adjusted net income is above £100,000." At £125,140 the allowance has gone entirely.

So each extra pound of income in that band does two jobs. It is taxed at 40% in its own right, and it strips away 50p of allowance, pushing 50p of previously tax-free income into the 40% band — another 20p of tax. Forty pence plus twenty pence is sixty pence, on every pound, across £25,140 of income.

Add employee National Insurance at 2% above the upper earnings limit and the combined marginal cost on employment income is 62%. Above £125,140 the rate falls back to 45% plus 2%. That is the odd shape of the UK system: a band in which a well-paid person pays a higher marginal rate than a very well-paid one.

The arithmetic, line by line

Take an employee whose income rises from £100,000 to £115,000 — a £15,000 bonus, no pension contributions, no other reliefs.

At £100,000 of adjusted net income

| Line | Working | Amount |

|---|---|---|

| Income | | £100,000 |

| Personal Allowance | Full allowance | (£12,570) |

| Taxable income | | £87,430 |

| Basic rate | £37,700 × 20% | £7,540 |

| Higher rate | £49,730 × 40% | £19,892 |

| UK income tax | | £27,432 |

At £115,000 of adjusted net income

| Line | Working | Amount |

|---|---|---|

| Income | | £115,000 |

| Allowance withdrawn | (£115,000 − £100,000) ÷ 2 | £7,500 |

| Personal Allowance | £12,570 − £7,500 | (£5,070) |

| Taxable income | | £109,930 |

| Basic rate | £37,700 × 20% | £7,540 |

| Higher rate | £72,230 × 40% | £28,892 |

| UK income tax | | £36,432 |

The bonus was £15,000. The extra income tax is £36,432 − £27,432 = £9,000. That is exactly 60%, before National Insurance. The employee keeps £5,700 of a £15,000 award, and nothing on the payslip explains why.

The whole band at a glance

UK income tax on employment income, 2026-27, England, Wales and Northern Ireland, with no reliefs and no other income:

| Adjusted net income | Personal Allowance | Allowance lost | UK income tax | Marginal rate on the step from the row above |

|---|---|---|---|---|

| £100,000 | £12,570 | £0 | £27,432 | — |

| £105,000 | £10,070 | £2,500 | £30,432 | 60% |

| £110,000 | £7,570 | £5,000 | £33,432 | 60% |

| £115,000 | £5,070 | £7,500 | £36,432 | 60% |

| £120,000 | £2,570 | £10,000 | £39,432 | 60% |

| £125,140 | £0 | £12,570 | £42,516 | 60% |

| £130,000 | £0 | £12,570 | £44,703 | 45% |

Where children change the picture

A great many articles claim the High Income Child Benefit Charge "stacks on top of" the 60% band. It does not, and the detail matters.

HICBC applies to adjusted net income above £60,000, at 1% of the Child Benefit received for every £200 of income over that figure. At £80,000 the charge equals the whole of the Child Benefit. A parent earning £100,000 or more has therefore already lost every penny of it, and there is nothing left to claw back inside the allowance taper.

What exists instead is an earlier high-marginal-rate band, between £60,000 and £80,000, which catches a different group of people — and which uses the adjusted net income of whichever partner has the higher income, not the claimant's.

Worked example: £60,000 to £70,000, two children

Child Benefit for 2026-27 is £27.05 a week for the eldest or only child and £17.90 for each additional child — £44.95 a week, or £2,337.40 a year, for two children.

| Line | At £60,000 | At £70,000 |

|---|---|---|

| Taxable income after the £12,570 allowance | £47,430 | £57,430 |

| Basic rate (£37,700 × 20%) | £7,540 | £7,540 |

| Higher rate at 40% | £3,892 | £7,892 |

| HICBC (50% of £2,337.40 at £70,000) | £0 | £1,168.70 |

| Total UK cost | £11,432 | £16,600.70 |

An extra £10,000 of salary costs £5,168.70 — an effective marginal rate of about 52%, or 54% with National Insurance. With three children the same £10,000 step costs about 56% before National Insurance, because the benefit being withdrawn is larger.

Two separate traps, then, at two separate income levels, and they are solved by different numbers. Our fuller treatment of the charge is in the High Income Child Benefit Charge guide.

Adjusted net income: what counts, and what reduces it

Both charges run off adjusted net income, which is neither salary nor taxable income. HMRC sets out a four-step calculation.

Step 1 — net income. Add together all taxable income: employment, self-employment profits, taxable state benefits, pensions, savings interest, dividends, rental profits, trust income and foreign income. Then deduct certain reliefs, including payments made gross to a pension scheme, and trading losses.

Step 2 — Gift Aid. Deduct the grossed-up amount of any Gift Aid donation: what you paid, multiplied by 1.25.

Step 3 — relief-at-source pension contributions. Where the provider has already added basic-rate relief, deduct the grossed-up amount — again, the payment multiplied by 1.25.

Step 4 — add back any relief taken at step 1 for trade union or police organisation superannuation payments, up to £100.

Three practical consequences follow.

• Investment income counts. Dividends, interest and rental profits can drag someone whose salary is £92,000 into the taper. Gross salary is the wrong number to watch, and it is the number most people watch.
• Three pension routes, three mechanics. A relief-at-source personal contribution of £8,000 becomes £10,000 gross and comes off at step 3. A net pay arrangement contribution never appears in taxable pay, so it has already reduced the step 1 figure. Salary sacrifice reduces contractual pay itself, so it never enters the calculation at all — and it saves employee and employer National Insurance too. The destination looks similar; the paperwork, the National Insurance result and, as we will see, the US analysis are not.
• Contributions are capped and dated. The annual allowance for pension savings is £60,000, with up to three previous tax years of unused allowance available to carry forward. A tapered annual allowance applies where threshold income exceeds £200,000 and adjusted income exceeds £260,000. The contribution must also be made before 5 April to affect that UK tax year — a deadline that sits awkwardly against the US calendar year.

Our note on how employers operate the sacrifice route is here.

The cross-border half: why the obvious UK fix can cost a US citizen

This is where most articles stop, and where US citizens in the UK most often receive advice that is correct in one country and expensive in the other.

A US citizen or green card holder files a US return on worldwide income wherever they live. Double taxation is normally relieved by the foreign tax credit: UK tax paid on UK-source income is credited against the US tax on that same income, computed on Form 1116. Because UK rates on employment income are generally higher than US federal rates, the common result is an excess credit position — more creditable UK tax than there is US tax to absorb. Excess credits can be carried back one year and forward ten. That surplus is an asset, and it is exactly what UK-only advice puts at risk.

Mechanism one — the credit pool shrinks

If a £15,000 pension contribution removes £9,000 of UK tax, it removes roughly £9,000 of creditable foreign tax in the same movement. Nothing may be payable to the IRS this year if the surplus is large. But the surplus is the buffer that absorbs the year you sell shares, exercise options, take a large bonus or pick up US-source income that no amount of UK tax can shelter. Credits expire after ten years, and a decade of diligent contributions can quietly flatten a pool that would otherwise have carried you through a one-off event.

Mechanism two — whether the US gives you the deduction as well

Everything turns on whether the same contribution also reduces your US taxable income. A UK workplace pension is not a US-qualified plan, so the answer comes from the treaty rather than from the Internal Revenue Code.

Article 18(5) of the US–UK Double Taxation Convention is the relevant provision. Where a US citizen who is resident in the UK exercises an employment in the UK, the income from that employment is taxable in the UK and is borne by a UK-resident employer or a UK permanent establishment, and the individual is a member or beneficiary of a UK pension scheme, then contributions paid by or on behalf of that individual are "deductible (or excludable) in computing his taxable income in the United States", and employer contributions and accruals are not treated as the employee's taxable income. The Article then limits itself: it "shall apply only to the extent that the contributions or benefits qualify for tax relief in the United Kingdom". Article 18(5) is written expressly for a US citizen resident in the United Kingdom, which is why practitioners rely on it. Note, though, that the saving clause in Article 1(4) lets the United States tax its citizens as if the treaty had not come into effect, and the list of exceptions in Article 1(5)(a) names paragraph 1 of Article 18 rather than paragraph 5. How those provisions sit together is a technical question on which you should take advice for your own facts rather than assume the relief is automatic.

Where every one of those conditions holds, the contribution reduces both tax bases. The lost credit is matched by a lower US liability before credit, and the direction of travel is broadly neutral — the carryforward is the main casualty.

Where a condition fails, the picture reverses. A personal SIPP contribution unconnected to a UK employment; a contribution by someone who is not UK resident; an amount that attracts no UK tax relief because the annual allowance is exhausted; an arrangement that does not fit the Article's wording. In each case US taxable income may be unchanged while creditable UK tax falls. That is a one-way loss: the same US income, less credit standing against it, a larger US bill.

Where the answer genuinely depends on facts

Which way it falls depends on your scheme, your residence, your income mix and your filing history. The variables that decide it are:

• whether you claim the foreign tax credit or the foreign earned income exclusion, and which categories your income falls into — see how foreign tax credit relief is actually calculated;
• how much US-source income you have, since no amount of UK tax can shelter it;
• the size and age profile of any existing credit carryforward;
• whether the treaty position has to be disclosed on Form 8833;
• the scheme type and how it is treated for US reporting, which we cover in US tax and UK pensions and SIPPs.

A caution before you act. Any pension or timing decision taken by a US person to escape the 60% band should be modelled on both returns — current year and carryforward — before the money moves. A contribution cannot be unwound, and in the wrong set of facts an irrecoverable US cost can exceed a 60% UK saving. This is the single most common place where competent UK advice and competent US advice, given separately, combine into a worse answer than either adviser would have reached alone.

Gift Aid and charitable giving across the two systems

Gift Aid is the other standard lever, and for a US person it is the harder one.

On the UK side it works cleanly. A charity "can claim an extra 25p for every £1 you give", and a higher-rate taxpayer claims the difference through Self Assessment — on a £100 donation grossed up to £125, "you can personally claim back £25.00 (£125 x 20%)". The grossed-up figure also comes off adjusted net income, so £8,000 given under Gift Aid reduces adjusted net income by £10,000. The condition is that you have paid enough UK tax to cover what the charity reclaims.

On the US side, a donation to a UK charity is generally not deductible at all. IRS Publication 526 places foreign organisations outside the definition of a qualified organisation, with narrow treaty exceptions for certain Canadian, Israeli and Mexican charities. There is no equivalent exception for the United Kingdom, and the US–UK Convention contains no article creating one.

For a US person giving under Gift Aid in the UK, then: UK tax falls, the US credit falls with it, and no US deduction arrives to compensate. Dual-qualified structures — charities or intermediaries recognised by both HMRC and the IRS — exist precisely to solve this, and the choice of vehicle usually matters more than the amount. We set out the options in charitable giving for US–UK dual taxpayers.

What to do, and when

1. Work out your adjusted net income early — by December, not in March. Include dividends, interest, rental profits and foreign income, not just salary.

2. Identify which band you are in. £60,000–£80,000 with children is a different problem from £100,000–£125,140, and the amounts that solve them differ.

3. Check your pension headroom before assuming a contribution is available: the annual allowance, carry-forward from the previous three years, and whether the taper applies to you.

4. If you file a US return, model both sides together — this year's US liability, this year's credit, and the effect on the carryforward balance.

5. Decide the route, not just the amount. Salary sacrifice, relief at source and net pay produce different National Insurance outcomes and different treaty analyses.

6. Act before 5 April for the UK year, allowing for payroll and scheme processing times, and keep the evidence for both filings.

7. Review after the Budget. With a Budget on 28 October 2026, confirm the thresholds are unchanged before committing to a plan built on them.

Common mistakes

• Watching gross salary instead of adjusted net income. Dividends and rental profits put people into the taper who are convinced they are nowhere near it.
• Assuming the Child Benefit charge adds to the 60% band. It does not. It has finished by £80,000.
• Treating a UK pension contribution as automatically deductible in the US. Article 18(5) has conditions, and failing one of them changes the answer completely.
• Forgetting the credit carryforward. A plan that looks neutral this year can be expensive in the year of a liquidity event.
• Giving under Gift Aid without checking the US position. The most efficient UK gift can be the least efficient cross-border one.
• Leaving it to March. Payroll cut-offs, scheme processing and employer sacrifice windows all close before 5 April.
• Taking £125,140 on trust in a Budget year. It is a derived figure — the point at which a £12,570 allowance has been fully withdrawn — so it moves whenever the allowance or the £100,000 limit moves.

Sources

• Income Tax rates and Personal Allowances — GOV.UK
• Personal Allowances: adjusted net income — GOV.UK
• Rates and thresholds for employers 2026 to 2027 — HMRC
• High Income Child Benefit Charge and Child Benefit rates — GOV.UK
• Tax on your private pension contributions: annual allowance — GOV.UK
• Gift Aid — GOV.UK
• 2001 UK–USA Double Taxation Convention as amended by the 2002 protocol — Articles 1, 18 and 24
• Foreign Tax Credit and Foreign Tax Credit — how to figure the credit — IRS
• Publication 526, Charitable Contributions — IRS
• Chancellor letter to the Treasury Select Committee — Budget 2026 date — HM Treasury

When it is worth getting help

If your only filing obligation is a UK one, the 60% band is arithmetic, and a good adviser will solve it in an afternoon. If you also file a 1040, it stops being arithmetic: one contribution moves two tax bases, one credit pool and a ten-year carryforward, and the right answer depends on facts a UK-only or US-only adviser will not have thought to ask about. That is the case for using tax specialists for US and UK rather than two advisers who never speak to each other.

At Next Tax Source, UK computations are reviewed by an ACCA-qualified accountant and US returns are reviewed and signed by a licensed CPA or Enrolled Agent, so the two sides are modelled against each other before anything is filed. If you would like your position modelled ahead of the 5 April contribution deadline, you can book a consultation. This article is general information about how the rules work, not advice on your circumstances.