Premium Bonds Calculator

Enter the amount of Premium Bonds you hold (between £25 and £50,000) and click Calculate. The tool estimates your expected annual and monthly prize winnings based on the current NS&I prize fund rate of 4.00% and odds of 1 in 21,000 per £1 bond per month.

The current odds of winning a prize are 1 in 21,000 per £1 bond per month. The prize fund rate is 4.00%. This means for every £1,000 held, you can statistically expect around £40 per year in prizes — though actual winnings are random and vary significantly.

Yes, all Premium Bonds prizes are 100% tax-free. This makes them particularly attractive for higher-rate and additional-rate taxpayers, as the effective return can be higher than taxable savings accounts offering similar headline rates.

The maximum holding is £50,000 per person. The minimum purchase is £25. You can buy bonds online through NS&I, by phone, or by post. Children can also hold Premium Bonds (purchased by a parent or guardian).

With a 4.00% prize fund rate, the average expected return matches a 4.00% savings account — but tax-free. For a basic-rate taxpayer, the tax-free equivalent is the same as a 5.00% taxable rate. For higher-rate taxpayers, it's equivalent to 6.67%. However, actual returns are random — you may win more or less than the average.

Prize values range from £25 to £1,000,000. There are two £1 million jackpot prizes each month. Most prizes are £25 or £50. The prize distribution is weighted towards smaller prizes, so most winners receive £25.

The draw takes place monthly. NS&I's ERNIE (Electronic Random Number Indicator Equipment) randomly selects winning bond numbers. Results are published on the 1st of each month, and you can check your prizes on the NS&I website or app.

Yes, you can cash in Premium Bonds at any time with no penalty. The money is usually returned to your bank account within a few working days. There is no lock-in period, making them a flexible savings option.