Lottery Win Interest Calculator: Live Off the Interest?

The win

Amount won (£)

Interest rate a year %Savings accounts and bonds pay different rates, and they change. Try a few.

Inflation a year %

You'd like to spend a year (£)

What it earns

Interest a year–

Interest a month–

Interest a week–

Spend a year and keep its value–

Years your spending lasts (if it never rises)–

Years it lasts if spending rises with inflation–

Interest = amount × rate. Real rate = (1 + rate) ÷ (1 + inflation) − 1. Years the money lasts = −ln(1 − interest ÷ spending) ÷ ln(1 + rate), with the real rate if spending rises with prices. Interest is assumed to be paid yearly; no tax is included.

Independent site. CasinoCalcs is not affiliated with or endorsed by any lottery operator, including the National Lottery, Allwyn and Ireland’s National Lottery. Game names are used only to describe the rules the maths is based on.

Maths reviewed by Josh Miller
Tested by Diana Westfield

Updated 10 Nov 2026How we calculate →

Spotted a wrong result?Report an error Corrections log

A £1 million lottery win earning 4% pays £40,000 a year in interest, about £769 a week. That’s the headline the CasinoCalcs lottery win interest calculator above starts with. Then it does the sums people forget: what you can spend each year without the win shrinking once inflation is counted, and how many years it lasts if you spend more. It’s a free calculator, and it uses the numbers you type in, not anyone’s sales pitch.

Lottery win interest calculator: the headline figure

Win	At 3%	At 4%	At 5%
£100,000	£3,000	£4,000	£5,000
£1 million	£30,000	£40,000	£50,000
£5 million	£150,000	£200,000	£250,000

Interest a year, before tax. Rates move all the time, so try a few in the calculator rather than trusting one number.

The inflation catch

Spend all £40,000 every year and in 20 years your million still says £1,000,000, but it buys about 40% less with 2.5% inflation. To keep its value you can only spend the real interest: (1.04 ÷ 1.025) − 1, about 1.46%. On £1 million that’s roughly £14,600 a year. Not exactly a life of leisure, which is the useful thing to know before telling the boss where to go.

How long the money lasts

Spend more than the interest and you start eating the win. At £60,000 a year from £1 million at 4%:

If your spending never rises: about 28 years
If it rises with 2.5% inflation: about 19 years

A £2 million win at the same spending lasts about 46 years with inflation counted. It’s still a big win, just not an endless one. If you’re wondering what the chances of getting there are, the lottery odds calculator has them, and the lottery expected value calculator shows what a ticket is worth on average.

The interest is the fun part. Buying the ticket is still a long shot. BeGambleAware.org is free and confidential if playing stops being fun.

Frequently asked questions

How much interest would £1 million earn?

£40,000 a year at 4%, about £3,333 a month or £769 a week. At 3% it's £30,000.

Could I live off the interest from a lottery win?

Only up to the real interest, after inflation, if you want the money to keep its value. At 4% interest and 2.5% inflation that's about £14,600 a year on £1 million.

How long would £1 million last at £60,000 a year?

About 28 years if your spending never rises, and about 19 years if it rises with 2.5% inflation, at a 4% interest rate.

Does this include tax?

No. Tax on interest depends on where you live and your other income, so the calculator shows the gross figures.