Pension Calculator UK
Model: monthly compounding at the growth rate you choose, contributions at the end of each month. Figures are in nominal terms — they are not adjusted for inflation, and no charges are deducted. Tax relief on contributions is not modelled: the monthly figure is the amount that actually lands in your pot. The 4% figure is a common drawdown rule of thumb, not a promise. Investments can fall as well as rise. Figures are estimates, not financial advice.
How much pension do you need?
The Pensions and Lifetime Savings Association (PLSA) publishes Retirement Living Standards — three benchmarks for what retirement actually costs in the UK, worked out with Loughborough University. The figures below are for a single person living outside London in 2026/27, and they assume your mortgage is paid off and you pay no rent. If you still rent or have mortgage payments in retirement, add those costs on top.
| Standard | Single person | Couple | What it buys |
|---|---|---|---|
| Minimum | £14,400 a year | £22,400 a year | Basic needs, budget supermarket shops, a week’s holiday in the UK, no car |
| Moderate | £31,300 a year | £43,100 a year | Financial security, a 3-year-old car, 2 weeks in Europe, eating out twice a month |
| Comfortable | £43,100 a year | £59,000 a year | More luxury, 3 weeks in Europe, a newer car, regular theatre and dining out |
The full new State Pension covers the floor but not the middle. It pays £241.30 a week in 2026/27, which is £12,547.60 a year. That is £1,852.40 short of even the Minimum standard for a single person, and £18,752.40 short of Moderate. Your private pension has to fill the gap.
How big a pot do you need?
A common rule of thumb is the 4% rule: you can draw 4% of your pot each year and expect it to last through retirement. On that basis, the pot you need is the gap divided by 0.04 — or 25 times the gap.
| Standard (single) | Target income | Gap after State Pension | Pot needed at 4% |
|---|---|---|---|
| Minimum | £14,400 | £1,852.40 | £46,310 |
| Moderate | £31,300 | £18,752.40 | £468,810 |
| Comfortable | £43,100 | £30,552.40 | £763,810 |
Those numbers assume you get the full new State Pension, which needs 35 qualifying years of National Insurance, and that you take the income at 4% a year. An annuity would give you a guaranteed income instead, but the rate depends on your age and health at the time you buy it, so it cannot be fixed in advance here. Check your own State Pension forecast at GOV.UK — many people get less than the full amount because of gaps in their National Insurance record or years contracted out before 2016.
Worked example: age 30, £10,000 pot, £200 a month, 5% growth
There are 37 years to age 67, which is 444 monthly contributions. Compounded monthly at 5% a year, the £10,000 starting pot grows to about £63,354 on its own, and the £200 a month grows to about £256,100. The total pot at 67 is about £319,455. You paid in £98,800 in total (£10,000 plus 444 × £200), so about £220,655 of the pot is investment growth. That is the power of starting early: the growth is worth more than twice what you paid in.
| Amount | |
|---|---|
| Starting pot | £10,000.00 |
| Total contributions (444 × £200) | £88,800.00 |
| Investment growth at 5% | £220,654.51 |
| Pot at 67 | £319,454.51 |
| Income at 4% drawdown | £12,778.18 a year |
| Plus full new State Pension | £12,547.60 a year |
| Total retirement income | £25,325.78 a year |
| Short of Moderate (£31,300) | £5,974.22 a year |
Starting ten years later changes everything. The same £200 a month from age 40, with the same £10,000 starting pot, reaches about £175,100 by 67 — little more than half. Starting at 25 instead of 30 adds about £104,000, taking the pot to roughly £423,600. Time in the market matters more than the monthly amount, which is why pension advisers repeat the same line: start now, even with a small amount, and increase it when your pay rises.
What the calculator does not include
- Tax relief. Personal pension contributions get basic-rate tax relief, so £200 from your pay can become £250 in the pot. Workplace pensions work differently again, with employer contributions on top. Auto-enrolment minimums are 8% of qualifying earnings in total — 5% from you and 3% from your employer — and that alone rarely delivers a moderate retirement.
- Inflation. The figures are nominal. At 2% inflation a year, £31,300 of spending power in 37 years’ time needs a much bigger pot in pounds of the day. Think of the result as today’s money only if you also think of the contributions as today’s money.
- Charges. Pension funds charge fees, typically 0.3% to 1% a year, which reduce growth. A 0.75% charge over 37 years takes a noticeable bite out of the final pot.
- State Pension age. State Pension age is currently 66 and rises to 67 between 2026 and 2028. The minimum age you can normally access a private pension is 55, rising to 57 from April 2028.
How much should you pay in?
A common rule of thumb is to pay in half your age as a percentage of your salary, including employer contributions: start at 30 and the target is 15%, start at 40 and it is 20%. It is only a rule of thumb, but it captures the real point — the later you start, the more you have to put in to reach the same pot. Auto-enrolment minimums are 8% of qualifying earnings in total (5% from you, 3% from your employer), and on their own they rarely deliver a moderate retirement: the PLSA’s own modelling suggests auto-enrolment minimums typically produce a pot of around £310,000, well short of the £468,810 needed for a moderate retirement on top of the State Pension.
The practical approach is to start at the auto-enrolment minimum if that is all you can afford, then raise your contribution by 1% a year, or send half of every pay rise into the pension before your spending adjusts to the new salary. If your employer offers matching contributions — paying in more if you do — take the full match first: it is an immediate, guaranteed return that no investment can beat. And if you get a bonus, consider paying some of it into the pension: it avoids income tax and National Insurance at the point it goes in, and if you are near the £100,000 personal allowance taper or the £60,000 Child Benefit charge threshold, a pension contribution can pull you back below the line.
Related: Compound Interest Calculator · Take Home Pay Calculator · 50/30/20 Budget Calculator
Sources: PLSA Retirement Living Standards 2026/27 (single: Minimum £14,400, Moderate £31,300, Comfortable £43,100; couples £22,400/£43,100/£59,000); GOV.UK “Your State Pension explained” (full new State Pension £241.30 a week, 35 qualifying years); GOV.UK “Check your State Pension forecast”. Checked 13 November 2026.