What Have Index Funds Returned in the UK? 10, 20 and 30-Year History
Every FIRE plan rests on one number you can’t control: the return on your investments. Assume too much and you retire on a pot that runs dry; assume too little and you work years longer than you needed to. Here’s what UK and global index funds have actually returned in sterling over 10, 20 and 30 years, what the bad decades looked like, and the return most UK FIRE planners use instead.
Published: 7 October 2026 at 07:08 · 8 min read
What Is the Average Return on Index Funds in the UK?
Over the last 20 to 30 years, global equity index funds have returned roughly 8–9.5% a year in sterling with dividends reinvested, while UK trackers such as the FTSE All-Share have returned around 6–6.5% a year. The last decade has been unusually strong for global funds, largely thanks to US technology companies. The table shows approximate annualised total returns in pounds to the end of 2024, before fund and platform fees:
| Period to end 2024 | Global equities (GBP) | UK equities (FTSE All-Share) | UK inflation (CPI) |
|---|---|---|---|
| 10 years (2015–2024) | ~11.5% a year | ~5.5% a year | ~3% a year |
| 20 years (2005–2024) | ~9.5% a year | ~6% a year | ~2.8% a year |
| 30 years (1995–2024) | ~8% a year | ~6.5% a year | ~2.5% a year |
| Since 1900 (real, after inflation) | ~5% a year | ~5% a year | — |
To put those percentages into pounds: £10,000 growing at 8% a year for 30 years becomes about £100,600, while at 6.5% it becomes about £66,100. Strip out inflation and the picture is more modest — at a 5% real return the same £10,000 is worth about £43,200 in today’s money. That real figure is the one that matters for FIRE, because your spending rises with prices too.
The very long-run figures come from academic studies of stock markets back to 1900, which find that both UK and world equities have beaten inflation by roughly 5% a year over more than a century, comfortably ahead of gilts and cash. For why the UK has lagged more recently, see FTSE 100 vs All-Share vs global trackers.
What Did the Bad Decades Look Like?
Long-run averages hide some brutal stretches: a UK investor in global shares made roughly nothing in sterling over the whole of 2000–2009, and UK shares fell around 70% in 1973–74. Averages are what you get if you hold on through all of it. The approximate falls below are measured in sterling, peak to trough:
| Episode | Approx. fall | What happened next |
|---|---|---|
| 1973–74 UK bear market | UK shares down ~70% | Sharp rebound in 1975, but high inflation eroded real returns for years |
| 2000–2003 dot-com crash | Global shares down ~45–50% | Took until around 2006–07 to recover |
| 2007–2009 financial crisis | UK shares down ~45%, global ~35–40% | A weaker pound cushioned global funds; recovery by 2010–13 |
| 2020 Covid crash | Global shares down ~25% in five weeks | Back to previous highs within about six months |
| 2022 inflation and rate rises | Global shares down ~8% for the year | Bonds fell too; both recovered over 2023–24 |
For someone still building their pot, a crash is uncomfortable but mostly harmless — monthly contributions buy more units at lower prices. For someone who has just retired early, a deep fall in the first few years can permanently dent a plan, because withdrawals lock in losses. That is sequence-of-returns risk, and it’s the main reason FIRE plans use a cautious withdrawal rate rather than the average return.
The good news is that time has historically smoothed the ride. Studies of UK markets since 1899 find equities have beaten cash in roughly nine out of ten ten-year periods, and in almost every period of 20 years or longer. Not guaranteed — but a strong case for a long time horizon.
What Return Should You Assume for FIRE in the UK?
Most UK FIRE planners assume a real return of around 4–5% a year for a mainly equity portfolio, after fees — a little below the long-run historical average. There are three good reasons to shade the historical numbers down:
- Fees. Historical index returns ignore costs. A global tracker at 0.15–0.25% plus a platform fee of 0.15–0.45% can take 0.3–0.7% a year off. Compare options in our guide to the cheapest index funds in the UK.
- Starting valuations. Part of the last 15 years’ US-led returns came from shares becoming more expensive relative to earnings. Many fund houses now publish 10-year forecasts for global equities below their long-run average.
- Bonds and cash. If you hold gilts, bond funds or a cash buffer as you approach FIRE, your blended return will be lower than an all-equity figure.
Working in real terms keeps everything in today’s pounds: your spending, your FIRE number and your pot. If your calculator works in nominal terms instead, use a nominal return of around 6–7% and increase spending by 2.5–3% a year. Mixing a nominal return with today’s spending is the most common way people overstate how soon they can retire. See how inflation affects your FIRE number for more.
How Much Difference Does the Return Assumption Make?
A huge amount over long periods: £500 a month for 30 years grows to about £343,000 at 4% a year but about £585,000 at 7%. The table shows what £500 a month into a Stocks & Shares ISA becomes at different annual returns. The 4% and 5% rows can be read as today’s money (real returns); the 7% and 9% rows are nominal figures, in future pounds:
| Annual return | After 10 years | After 20 years | After 30 years |
|---|---|---|---|
| 4% (cautious real) | £73,300 | £181,900 | £342,600 |
| 5% (long-run real) | £77,200 | £202,900 | £407,700 |
| 7% (typical nominal) | £85,500 | £253,800 | £584,700 |
| 9% (strong nominal) | £94,900 | £319,400 | £851,100 |
Contributions total £60,000, £120,000 and £180,000 respectively. Over 10 years the return assumption barely matters — your savings rate does the heavy lifting. Over 30 years, growth dominates. That is why it pays to plan on a cautious figure and treat anything better as a bonus that brings your FIRE date forward, rather than the other way round.
Hold these funds inside an ISA or SIPP and the whole return is yours: no tax on dividends or gains (SIPP withdrawals are taxed as income above the 25% tax-free portion). In a general investment account, dividends above £500 and gains above £3,000 a year are taxable in 2025/26 — current rates are on gov.uk.
How Do Returns Link to the 4% Rule?
The 4% rule is not the same as assuming a 4% return: it is the withdrawal rate that survived the worst historical sequences, including the bad decades above, over 30 years. It was built from US data; UK and global studies suggest something closer to 3.25–3.75% is safer for a 40- or 50-year early retirement funded from a global portfolio. You can read more in our guide to the 4% rule in the UK.
UK early retirees also have a buffer US-based studies ignore: the full new State Pension of £11,502 a year from 67 (2025/26), rising with the triple lock. Once it starts, it reduces how much your portfolio has to provide. Check your forecast at gov.uk/check-state-pension.
Frequently Asked Questions
What is the average return on index funds in the UK?
It depends on the index and the period. In sterling terms, with dividends reinvested, global equity trackers have returned roughly 8% to 9.5% a year over the last 20 to 30 years, and around 11% to 12% a year over the last decade. UK trackers such as the FTSE All-Share have returned closer to 6% to 6.5% a year over 20 to 30 years. After UK inflation of around 2.5% to 3% a year, long-run real returns from global equities have been roughly 5% to 6% a year. These are historical figures, not promises.
What return should I assume for FIRE planning in the UK?
Many UK FIRE planners assume a real return (after inflation) of around 4% to 5% a year for a mostly equity portfolio, after fund and platform fees. That is a little below the long-run historical average, which builds in a margin for higher starting valuations today and for fees. Using a real return lets you keep your FIRE number and spending in today's pounds. If you prefer to work in nominal terms, something like 6% to 7% a year with spending rising at 2.5% to 3% a year is broadly equivalent.
Have index funds ever lost money over 10 years?
Yes. A UK investor in global equities from the start of 2000 to the end of 2009 made roughly nothing in sterling terms over the whole decade, and less than nothing after inflation, because of the dot-com crash and the 2008 financial crisis. Japanese equities took more than 30 years to regain their 1989 peak. Losing ten-year periods are uncommon for diversified equity funds but they do happen, which is why FIRE plans use conservative return assumptions and a safe withdrawal rate.
Are index fund returns taxed in the UK?
Not inside a Stocks & Shares ISA or a SIPP, where growth and dividends are free of UK tax (SIPP withdrawals are taxed as income, apart from the 25% tax-free portion). In a general investment account, dividends above the £500 dividend allowance and gains above the £3,000 capital gains tax allowance are taxable in 2025/26. Over 20 or 30 years, tax drag in a general account can cost a meaningful slice of the returns shown in historical tables.
Do past index fund returns predict future returns?
Not reliably. Long-run history tells you roughly what a diversified equity portfolio has delivered and how bumpy the ride has been, but the starting point matters. Part of the strong US-led returns of the last 15 years came from share prices rising faster than company earnings, which may not repeat. Use history to set a sensible range and to prepare for bad decades, not as a forecast.
Work Out Your Own Numbers
Plug a cautious return into our free calculators and see what it means for your plan:
- Safe Withdrawal Rate Calculator — test how much income your pot can sustain at different withdrawal rates and return assumptions
- FIRE Number Calculator — work out the ISA and SIPP pot you need for your annual spending, and how a 4% or 5% real return changes your timeline
Ready to invest? Read our guide on how to buy index funds in the UK or our pick of the best global index funds.
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