How do I calculate an inflation adjusted return?

Divide (1 + your return) by (1 + inflation) and subtract 1. A 7% return with 3% inflation is a 3.88% real return.

Why not just subtract inflation from my return?

Subtraction is only an approximation. It overstates your real gain, slightly at low rates and significantly when inflation is high.

What is the UK inflation rate used for adjusting returns?

CPI is standard measure and Bank of England's 2% target metric. The ONS publishes it monthly and CPIH and RPI exist as variants for specific uses.

Can a real return be negative while my balance grows?

Yes and it happens often with cash. Any year your return sits below inflation, your spending power fell despite the bigger balance.

What is a good real return?

Long run equity investors have historically earned 5 to 7% real. Anything consistently above 0% beats cash under mattress and above 3% real compounds into serious wealth over decades.

Do any UK investments guarantee beating inflation?

Index linked gilts adjust with inflation by design, though their prices still fluctuate before maturity. No mainstream savings account guarantees a positive real return.

Specialist Calculator

Inflation Adjusted Return Calculator UK

Name: Inflation Adjusted Return Calculator UK
Author: CalZone

Find out what your investments really earned once rising prices are stripped out. Enter your nominal return, inflation rate and calculator gives your real return, number that measures actual gains in spending power.

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Nominal vs Real: The Only Return That Buys Anything

A nominal return is headline percentage your account shows. The real return is what is left after inflation and it is honest measure because you invest to buy things later, not to accumulate bigger numbers. Earn 6% in a year when prices rose 4% and your spending power grew by only around 1.9%, not 2%, because correct formula divides rather than subtracts:

Real return = ((1 + nominal) ÷ (1 + inflation)) − 1

So (1.06 ÷ 1.04) − 1 = 1.92%. Subtracting gives a close approximation at low rates but drifts badly when either number is large, a 10% return during 9% inflation is a real gain of just 0.9%, and a 4% savings rate during 10% inflation is a real loss of 5.5% even though the account balance rose.

What Inflation Does to Money Over Time

UK inflation is targeted at 2% (measured by CPI) but has averaged nearer 3% over recent decades and spiked above 11% in 2022. Compounding works against idle cash exactly as it works for investments:

Inflation rate	£10,000 buys this much after 20 years
2%	£6,730
3%	£5,540
5%	£3,770
That table is case for investing at all. Money that merely holds its nominal value is quietly shrinking and even interest paying accounts lose ground whenever the rate sits below inflation, which has been true for cash across most of the past two decades.

Real Returns by Asset: The Long Run Picture

Over long periods, UK and global equities have delivered roughly 5 to 7% a year above inflation, which is why stock market remains the standard tool for growing wealth in real terms. Cash has managed around 0 to 1% real over the long run and negative stretches lasting a decade or more. Bonds sit between.

For inflation protection specifically, UK issues index linked gilts whose payments rise with inflation and the State Pension triple lock guarantees at least inflation matching upgrades, but ordinary fixed savings rates carry no such promise.

The practical planning consequence, always project long term goals in real terms. A pension pot forecast of £500,000 in 30 years sounds enormous, but at 2.5% inflation it buys what roughly £238,000 buys today. Planning with a real return of 3 to 5% for equities produces smaller, truer numbers than gross projections.

Checking Your Own Real Return

Take your portfolio's return for any period, find CPI inflation for same period from the ONS and run the division formula. Do it after fees, since a 6% return with 1% charges during 3% inflation is a real return of about 1.9%, not 3%. Fees and inflation stack as two permanent headwinds every investment must clear before you are genuinely better off.