The Pension Tax Trap: What HMRC Takes When You Finally Retire

The pension tax relief system is built on a simple exchange: you defer income today, HMRC gives you tax relief, and when you take the money in retirement, it is taxed as income then. The logic is that you will be in a lower tax bracket in retirement than in your working years. For many people who diligently saved, this assumption has quietly broken down. The state pension alone now pays £11,502 per year. Add a private pension — even a modest one — and the personal allowance is consumed before you have spent a single pound of savings you chose to make.

The result is a retirement tax bill that surprises even financially informed retirees. The tax relief you received going in was real. The tax due coming out is also real. And from 2027, a new dimension arrives: pension pots will be brought into the scope of inheritance tax for the first time, meaning unspent pension wealth above the IHT threshold will be taxed at 40% on death.

How Pension Taxation Works at Retirement

Defined contribution (DC) pensions — including workplace pensions, SIPPs, and personal pensions — give you tax relief on contributions at your marginal income tax rate. A higher rate taxpayer contributing £10,000 receives £4,000 back via tax relief (claimed through self-assessment), meaning the net cost is £6,000. A basic rate taxpayer receives £2,000 automatic tax relief, reducing the net cost to £8,000.

At retirement, typically from age 55 (rising to 57 in 2028), you can access your DC pension. Up to 25% can be taken as a Pension Commencement Lump Sum (PCLS) — the tax-free lump sum — up to a cap of £268,275 (set in April 2024 when the old lifetime allowance was abolished). The remaining 75% of withdrawals, whether taken as flexible drawdown or used to purchase an annuity, is taxable income.

Defined benefit (DB) pensions — final salary or career average schemes, common in the public sector — pay a guaranteed annual income for life, taxed in the same way as other pension income. A public sector worker with a DB pension of £25,000/year plus the state pension of £11,502 has a total pension income of £36,502 — putting them firmly in the 20% income tax band from the first pound drawn above the personal allowance.

The 25% Tax-Free Lump Sum Explained

The tax-free lump sum is the most valuable structural feature of the UK pension system. Up to 25% of your defined contribution pension can be taken free of all income tax, up to a maximum of £268,275. This cap was introduced in April 2024 when the lifetime allowance was abolished — previously, 25% of the lifetime allowance (then £1,073,100) was £268,275, and the cap preserved this amount in cash terms.

The strategic question is when and how to take the tax-free cash. Options include: taking it all at once at retirement (maximising the immediate tax-free sum), taking it in tranches using Uncrystallised Fund Pension Lump Sums (UFPLS — where each withdrawal is 25% tax-free and 75% taxable), or taking a full PCLS at outset and drawing taxable income thereafter from the remaining 75%.

For pension pots above £1,072,300 (where 25% exceeds the £268,275 cap), the surplus above the cap is fully taxable on withdrawal. A pension of £2 million, for example, has a tax-free entitlement of £268,275 — representing only 13.4% of the total fund, not 25%. The remainder is fully taxed as income.

When Pension Income Triggers 40% Tax

Higher rate income tax (40%) applies to income between £50,270 and £125,140 in 2025/26. For a retiree drawing pension income, all sources are aggregated: state pension, private pension drawdown, DB pension, part-time employment income, rental income. Many retirees with moderately sized pension pots find themselves in 40% territory without realising it.

2025/26 rates. Personal allowance £12,570. Basic rate 20% on £12,570–£50,270, higher rate 40% above £50,270. State pension £11,502 (full new state pension 2025/26). Figures are estimates.

The Personal Allowance Trap

The state pension for 2025/26 is £11,502 per year — the result of the triple lock uprating (higher of CPI, earnings, or 2.5%). The personal allowance is £12,570, frozen until at least 2028. This means retirees drawing only the state pension currently have a £1,068 buffer before any income tax is due. But the gap is narrowing by design: with the triple lock increasing the state pension each year and the personal allowance frozen, the state pension will exceed the personal allowance — probably around 2027/28 — meaning all state pension recipients will owe income tax on it automatically for the first time in history.

IHT on Pensions from 2027

Currently, unspent defined contribution pension pots sit outside your estate for inheritance tax purposes — one of the most powerful IHT planning tools available. On death, pension funds pass to nominated beneficiaries free of IHT, and if the pension holder dies before 75, beneficiaries receive the fund tax-free entirely. This has made pension pots a favoured vehicle for intergenerational wealth transfer.

From April 2027, following the October 2024 Budget announcement, pension pots will be brought into the scope of inheritance tax. Unspent pension wealth above the £325,000 nil-rate band (combined with other estate assets) will attract 40% IHT. The IFS estimates this change will affect approximately 8% of estates — predominantly those of higher earners who have maximised pension contributions. The total projected Treasury yield is approximately £1.5–2 billion per year by 2029/30.

The practical implication: spending down pension assets in retirement, making use of drawdown flexibility to stay within tax bands, and using other tax-free wrappers (ISAs, VCTs, EIS) for assets intended for heirs may now be more advantageous than preserving pension wealth for inheritance.

Strategies to Minimise Your Retirement Tax Bill

• Manage drawdown to stay in the basic rate band: Withdraw up to approximately £50,270 per year from all sources. Income above this level is taxed at 40%. Spacing withdrawals over multiple tax years can dramatically reduce the lifetime tax bill on large pots.
• Take the tax-free lump sum strategically: The PCLS can be invested in an ISA (up to £20,000/year) post-retirement — sheltering future growth from income tax and CGT permanently.
• Consider a phased retirement approach: Rather than retiring fully at 55 or 60, drawing small amounts from pension alongside continuing employment (at reduced hours) keeps total income in lower tax bands.
• ISA contributions pre-retirement: ISA income and withdrawals in retirement are not counted as taxable income — they do not affect the personal allowance, do not trigger the withdrawal of age-related allowances, and do not count toward the 40% threshold.
• Spouse/partner planning: If one partner has a lower income in retirement, shifting assets to them during the accumulation phase can maximise use of two personal allowances and two sets of tax bands.