How to use the Premium Bonds calculator
- 1 Enter how much you hold in Premium Bonds, from £25 to £50,000.
- 2 Check the prize fund rate and odds; they default to NS&I's current figures.
- 3 Enter a savings rate to compare and choose your tax band.
- 4 Read the expected prizes, the odds and the comparison.
Worked example
£10,000 in Premium Bonds at 4.35% and 21,000 to 1. You would expect about 5.7 prizes a year, with a 37.9% chance of winning something each month and only a 0.3% chance of winning nothing all year. The average return is £435, but if every prize were £25 you would get about £143. A 4% savings account pays £400 to a basic-rate taxpayer, inside the £1,000 allowance.
Making Premium Bonds work for you
- Turn on prize reinvestment so winnings buy more bonds.
- Use your allowances first: basic-rate taxpayers often do better in a savings account.
- Check unclaimed prizes with the NS&I prize checker.
- Hold bonds a full calendar month before they enter a draw.
Compare with the Savings Interest Calculator and the ISA Calculator, and see what inflation does to cash with the Inflation Calculator.
Features
Odds explained
Turns 21,000 to 1 per bond into your chance of a prize each month.
Realistic range
Shows the prize fund average and a low-end estimate if every prize is £25.
Tax comparison
Compares tax-free prizes with taxable interest after the Personal Savings Allowance.
When to use it
Choosing where to save
Compare bonds with an easy-access account. Work out interest with the Savings Interest Calculator.
Higher-rate taxpayers
See the taxable rate you would need to match tax-free prizes. Check your allowance with the ISA Calculator.
Deciding how much to hold
See how the chance of a prize each month grows with your holding.
Gifts for children
Bonds can be bought for children under 16 by parents or grandparents.
Related Savings and Investing tasks
Frequently asked questions
What is the Premium Bonds prize fund rate?
4.35% from the September 2026 draw, up from 3.80% in July. It is the average rate at which prizes are paid out over a year, not a guaranteed return.
What are the odds of winning a Premium Bond prize?
21,000 to 1 for each £1 bond in each monthly draw, from September 2026. With £10,000 you would expect about 0.48 prizes a month, or 5.7 a year, on average.
How much will I win with £10,000 in Premium Bonds?
At the 4.35% prize fund rate the average is £435 a year, but most people win less, because a few large prizes raise the average. If every prize you won were £25, about 5.7 prizes would be worth around £143.
Are Premium Bond prizes taxable?
No. All prizes are free of UK Income Tax and Capital Gains Tax, which makes them more attractive for higher-rate taxpayers who have used their Personal Savings Allowance.
What is the most I can hold?
£50,000 per person. The minimum purchase is £25.
Can I lose money in Premium Bonds?
Your capital is 100% backed by HM Treasury, so you cannot lose what you put in. But if you win nothing, inflation reduces its buying power.
How often is the draw?
Every month. Prizes range from £25 to £1 million, with two £1 million jackpots each month.
When do new bonds enter the draw?
Bonds must be held for a full calendar month before they are entered, so money paid in during October first goes into the December draw.
Why does the rate change?
NS&I adjusts the prize fund rate and odds to balance savers, taxpayers and its funding target. It changed three times in 2026: down in April, then up in July and September.
Results are estimates based on the official rates linked above. Confirm important figures with the issuing authority or a qualified adviser before you act on them.
Built and reviewed by Hamza Farooq, founder and lead developer
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