Key facts
- Real return is your savings rate minus inflation: 4.5% savings at 3% inflation gives about 1.5% in buying power
- UK CPI was 2.8% in the year to April 2026; this guide uses 3% as a round working rate
- At 3% inflation, £10,000 buys only about £7,441 of goods in 10 years if held as cash
- An account paying 2% while inflation runs at 3% loses about minus 1.0% of buying power each year
Check the latest figure and your own numbers in the inflation calculator, and see how compounding can outpace inflation in compound interest guide or the wealth-building focus in our compound interest wealth guide.
| Savings rate | Inflation | Real return |
|---|---|---|
| 2.0% | 3.0% | minus 1.0% |
| 3.0% | 3.0% | 0.0% |
| 4.5% | 3.0% | plus 1.5% |
| 5.0% | 3.0% | plus 2.0% |
Real return is the savings rate minus inflation. Source: WhatsUK calculation at 3% inflation, 16 June 2026.
UK CPI inflation was 2.8% in the year to April 2026, with CPIH at 3.0%, and the Bank of England expects it around 3% or a little higher later in 2026. Inflation is updated monthly, so this guide uses 3% as a round working rate. For the latest figure, use our inflation calculator.
Even cash that earns interest can lose ground. Leave £10,000 in an account paying 2% while inflation runs at 3%, and after ten years you have £12,190 on paper but only about £9,070 of buying power in today's money, a real loss of around £930. At 3% inflation, prices roughly double every 23 to 24 years, which is why holding too much in cash for the long term has a hidden cost.
Your emergency fund is the exception: keep it in cash for safety even at a small real loss, as explained in emergency fund guide, and compare savings rates with the savings calculator.
What Is a Real Return?
Your nominal return is the interest rate your savings account advertises, for example 4.5% AER. Your real return is what you actually gain in purchasing power after accounting for inflation. The simplified formula is:
Real Return Formula
Real Return ≈ Nominal Interest Rate minus Inflation RateExample: 4.5% savings rate minus 3.0% inflation = plus 1.5% real return
Example: 3.0% savings rate minus 3.0% inflation = 0% real return (treading water)
Example: 2.0% savings rate minus 3.0% inflation = minus 1.0% real return (losing money in real terms)
The precise formula (Fisher equation) is: (1 + nominal) ÷ (1 + inflation) minus 1, but the simplified version above is accurate enough for everyday planning.
How Inflation Erodes Cash Over Time
| Starting Amount | Inflation Rate | After 10 Years (Real Value) | After 20 Years (Real Value) |
|---|---|---|---|
| £10,000 | 2.0% | £8,203 | £6,730 |
| £10,000 | 3.0% | £7,441 | £5,537 |
| £10,000 | 3.5% | £7,089 | £5,026 |
| £10,000 | 5.0% | £6,139 | £3,769 |
This table shows the purchasing power of £10,000 kept in cash with zero interest. At 3.5% inflation, roughly the UK long-run average, cash loses nearly a third of its real value in 10 years and half in 20 years.
UK Inflation Calculator
Enter an amount and inflation rate to see how purchasing power changes over any time period.
UK Inflation in Context
| Period | Average UK CPI | Notes |
|---|---|---|
| 2010 to 2019 | ~2.2% | Post-financial crisis low-inflation decade |
| 2020 | ~0.9% | COVID demand collapse |
| 2021 | ~2.5% | Energy and supply chain pressures begin |
| 2022 (peak) | ~9.1% | Russia-Ukraine war; energy price spike; Oct peak 11.1% |
| 2023 | ~6.8% | Inflation falling but still elevated |
| 2024 | ~2.5% | Returning toward Bank of England 2% target |
| 2025 to 2026 | ~2.5 to 3.0% | Slightly above target; services inflation sticky |
Savings Rates That Beat Inflation (2026/27)
The good news for savers in 2026 is that savings rates have risen substantially. After years of near-zero rates post-2008, you can now access accounts paying 4 to 5% AER, which comfortably beats the current inflation rate. The key is to find these accounts and move cash that is sitting in low-rate accounts.
| Account Type | Typical Rate (2026) | Real Return vs 3% Inflation | Key Features |
|---|---|---|---|
| Easy-access savings | 4.5 to 5.0% | plus 1.5% to plus 2.0% | Instant access, variable rate |
| 1-year fixed bond | 4.5 to 5.0% | plus 1.5% to plus 2.0% | Rate locked; money tied up |
| Cash ISA (easy-access) | 4.0 to 4.5% | plus 1.0% to plus 1.5% | Tax-free; £20,000/yr allowance |
| Premium Bonds (prize rate) | ~4.4% equivalent | ~plus 1.4% | Tax-free, capital guaranteed, variable |
| Standard current account | 0 to 1% | minus 2.0% to minus 3.0% | Poor for savings |
ISA vs Savings Account: The Tax Angle
For basic-rate taxpayers, the £1,000 Personal Savings Allowance (PSA) means interest up to £1,000 is tax-free regardless of account type. At 5% AER, you would need a balance of £20,000 before paying tax. Most people are covered. Higher-rate taxpayers only get a £500 PSA, and additional-rate taxpayers get nothing.
If you are a higher earner or have significant savings, a Cash ISA becomes more valuable. All interest earned inside an ISA is tax-free, and the wrapper carries forward indefinitely. Unlike the PSA, which resets each year but does not protect growth from previous years.
Beyond Cash: Beating Inflation Long-Term
Cash savings are ideal for short-term goals and emergency funds. But for money you will not need for 5+ years, cash often fails to beat inflation over the long run. Consider:
- Stocks and shares ISA: UK equities have returned roughly 7 to 9% per year on average over the long run (before inflation), well above the 2.5 to 3.5% long-run inflation average.
- Index-linked gilts: UK government bonds where returns are linked to RPI inflation. Low real return but capital-protected in real terms.
- Property: UK house prices have broadly tracked or exceeded inflation over the long term, though with high transaction costs and illiquidity.
- Pension contributions: Tax relief makes pension contributions one of the highest-return investments available. A basic-rate taxpayer effectively gets a 25% uplift on contributions.
The Two-Pot Strategy
Keep 3 to 6 months' expenses in an accessible easy-access account earning 4%+. Everything beyond your emergency fund that you will not need for 5+ years should be working harder in a stocks and shares ISA or pension, where long-run returns comfortably beat inflation.The Rule of 70: How Fast Inflation Halves Your Money
A quick mental model: divide 70 by the inflation rate to find how many years until purchasing power halves.
- At 2% inflation: 70 ÷ 2 = 35 years to halve
- At 3% inflation: 70 ÷ 3 = ~23 years to halve
- At 5% inflation: 70 ÷ 5 = 14 years to halve
- At 10% inflation: 70 ÷ 10 = 7 years to halve
At the 2022 peak of 11.1%, purchasing power would have halved in just over 6 years if sustained. This is why even short bouts of high inflation are so damaging to long-term savings.
Related Calculators
Frequently Asked Questions
A real return is your savings interest rate minus the inflation rate. If your savings account pays 4.5% AER and CPI inflation is 3%, your real return is 1.5%. If inflation exceeds your interest rate, your real return is negative, meaning your money loses purchasing power despite growing in nominal terms.
To beat inflation in 2026, your savings account needs to pay more than the current CPI rate (check ONS for the latest figure). The Personal Savings Allowance means the first £1,000 of interest (£500 for higher-rate taxpayers) is tax-free for 2026/27, which helps your effective real return.
The Rule of 70 estimates how many years it takes for inflation to halve the purchasing power of your money. Divide 70 by the inflation rate. At 3% inflation, your money loses half its purchasing power in approximately 23 years (70 divided by 3 = 23.3).
For money you need within 5 years, cash savings are generally safer. For longer time horizons, investing in a diversified stocks and shares ISA has historically beaten inflation by 4 to 5% per year on average. Past performance is not guaranteed, and investments can lose value in the short term.
UK CPI inflation was 2.8% in the year to April 2026, with CPIH at 3.0%, against the Bank of England target of 2%. The Bank expects inflation around 3% or a little higher later in 2026. It is published monthly by the ONS, so always check the latest figure before making decisions.
Subtract the inflation rate from your savings rate. A 4.5% account with 3% inflation gives roughly a 1.5% real return. For a precise figure, divide one plus the savings rate by one plus the inflation rate and subtract one, which gives 1.46% in this case, close to the simple estimate.
Yes. If your savings rate is below inflation you get a negative real return, meaning your money buys less over time even though the balance grows. At 3% inflation, an account paying 2% loses about 1% of its buying power each year, so chasing a competitive rate matters.
At 3% inflation, £10,000 keeps only about £8,626 of buying power after 5 years, £7,441 after 10 years and £5,537 after 20 years. Prices roughly double every 23 to 24 years, which is why cash suits short-term safety rather than long-term growth.
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James Hartley is a Chartered Management Accountant (CIMA) with more than eight years of experience in UK tax, payroll and compliance. He holds a BSc in Finance and Economics from the University of Manchester and spent his early career at a Big 4 accounting firm. He founded WhatsUK to build free UK financial calculators and guides verified against official HMRC sources. He authors every calculator and article on WhatsUK.
Sources & Official References
- ONS - Consumer Price Inflation, UK- Monthly CPI data and historical series
- Bank of England - Inflation and the 2% Target- BoE mandate and inflation targeting framework
- HMRC - Personal Savings Allowance- PSA rates for basic, higher, and additional rate taxpayers
- Moneyfacts - Savings Best Buys- Current best easy-access and fixed bond rates
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Disclaimer: This calculator provides estimates based on standard HMRC rates for 2026/27. Results may vary based on individual circumstances. This is not financial advice. Always consult a qualified accountant or CIMA-qualified financial adviser for personal tax matters.