Pension or ISA? Where to Put Your Savings
Both shelter your money from tax. The difference is when the taxman takes his cut: pensions give you the break on the way in, ISAs on the way out. For retirement saving the pension usually wins, and the maths shows exactly why and by how much. But ISAs earn their place, and two rule changes coming in 2027 shift the picture for both.
The two deals, side by side
| Pension | ISA | |
|---|---|---|
| Money going in | Tax relief at your rate (20% to 45%), plus employer money in a workplace scheme | From taxed income, no top-up |
| While invested | No UK tax on growth | No UK tax on growth |
| Money coming out | 25% tax-free, the rest taxed as income | All tax-free |
| When you can take it | From 55 (57 from April 2028) | Any time |
| Annual limit | £60,000 (and up to 100% of earnings for your own contributions) | £20,000 across all ISAs in 2026/27 |
The maths: same money, different outcomes
Take £100 of gross pay and a basic-rate taxpayer in both work and retirement. Ignore growth, since it multiplies both sides equally.
- Via a pension: the full £100 goes in thanks to tax relief. Coming out, 25% is tax-free and 75% is taxed at 20%, leaving £85.
- Via an ISA: tax first, so £80 goes in. It comes out untouched: £80.
The pension wins by 6.25%, entirely because of the 25% tax-free lump sum. Pay 40% tax now but 20% in retirement, which is common, and the same £100 becomes £85 in the pension against £60 in the ISA, a 42% advantage. Our sums, and the pattern holds at any growth rate.
Employer money settles the argument
Inside a workplace pension your employer adds at least 3% of qualifying earnings, and many add more if you do. No ISA gets employer money. Whatever else you decide, contribute enough to take every pound of match before an ISA sees a penny of long-term savings.
When the ISA wins
- You might need the money before 57. A pension is locked until then (55 now, 57 from April 2028). House deposit, career break, emergency fund: ISA territory. A locked-up bargain is no bargain if it forces you into expensive debt at 40.
- You have no earnings to get relief on. Pension tax relief needs earnings, a small £3,600 gross allowance aside. Non-earners with savings to place may find the ISA simpler.
- You expect a higher tax rate in retirement than now. Rare, but it flips the maths.
The Lifetime ISA, the hybrid
If you're 18 to 39, the Lifetime ISA blends the two: pay in up to £4,000 a year (inside the £20,000 total) and the government adds 25%, with tax-free withdrawals from 60, or earlier for a first home (source: GOV.UK). For a basic-rate taxpayer without an employer match on offer, a LISA rivals a pension. The catch is the 25% government charge for taking money out early for anything else, which claws back more than the bonus. Self-employed savers in particular often run a pension and a LISA together.
Two 2027 changes worth knowing now
- The cash ISA cap shrinks. From 6 April 2027, savers under 65 can put at most £12,000 of the £20,000 allowance into cash ISAs; the rest must go to stocks and shares or other non-cash ISAs to use the full allowance (Autumn Budget 2025; source: GOV.UK). Those aged 65 and over keep the full £20,000 cash limit.
- Pensions join inheritance tax. From 6 April 2027, unused pension pots are due to count as part of your estate for inheritance tax, weakening what was a big pension advantage. Our death benefits guide covers the detail.
See what the pension route builds
Put your numbers into the free calculator, including employer contributions, and see your projected pot. No sign-up, assumptions in the open.
Try the calculator →A sensible order for most people
- Workplace pension up to the full employer match.
- An emergency fund in easy-access savings or a cash ISA, three to six months of spending.
- Then by goal: retirement money to the pension for the relief, sooner-than-57 money to an ISA, and a LISA if you're young enough and it fits.
The wrong question is "which is better?" The right one is "when do I need which pound?" Most people end up wanting both.
Common questions
Is a pension or an ISA better?
For retirement saving the pension usually wins, thanks to tax relief going in, the 25% tax-free lump sum coming out, and employer money in a workplace scheme. An ISA is better for money you might need before 57, since a pension is locked until then.
Can I have both?
Yes, and most people should. They have separate annual limits, £60,000 for pensions and £20,000 across ISAs in 2026/27. A common approach is a pension for retirement money and an ISA for anything you may need sooner.
Which is better for a house deposit?
An ISA, because a normal pension can't be touched until 55 (57 from April 2028). If you're a first-time buyer under 40, a Lifetime ISA adds a 25% bonus on up to £4,000 a year towards a first home.
What's changing with cash ISAs in 2027?
From 6 April 2027, savers under 65 can put at most £12,000 of their £20,000 ISA allowance into cash ISAs, with the rest going to stocks and shares or other non-cash ISAs. Savers aged 65 and over keep the full £20,000 cash limit.
Sources
- Pension tax relief, 25% tax-free lump sum and £60,000 annual allowance: GOV.UK / HMRC.
- ISA allowance £20,000 (2026/27) and Lifetime ISA rules: GOV.UK.
- Cash ISA £12,000 limit for under-65s from 6 April 2027: GOV.UK (Autumn Budget 2025); confirmed by Which? and MoneySavingExpert.
- Pensions within inheritance tax from 6 April 2027: GOV.UK policy paper. Figures correct as of July 2026.
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This article is for general information only and does not constitute financial advice. The comparisons are illustrations based on 2026/27 tax rules, correct as of July 2026; the 2027 changes described were announced but details can change before they take effect. Tax treatment depends on individual circumstances. For advice tailored to you, speak to a financial adviser regulated by the Financial Conduct Authority (FCA), or get free guidance from MoneyHelper.