Millions of Premium Bond holders will have a better chance of winning from next month as NS&I is boosting the prize fund, following last week's Bank of England base rate rise.

The change, which comes after the prize pool was cut earlier this year, means that from Friday 1 December your odds of winning something each month with each £1 bond will improve from 30,000 to 1 to 24,500 to 1.

Premium Bonds are effectively a savings account you can put money into, where instead of savers earning interest, tax-free prizes are awarded in a monthly prize draw – meaning there's no guarantee you'll get any return on your money.

Prizes range from £25 to £1 million, and as of 1 December the estimated number of Premium Bond prizes will rise, from 2,375,944 in November to 2,906,305 – the highest number of prizes in any Premium Bonds draw to date. The total value of prizes will also rise from £68,308,325 this month to an estimated £83,071,775 in December.

It's worth bearing in mind that the nearest thing Premium Bonds have to an interest rate is their annual prize rate, which means 'on average' the return will rise from 1.15% to 1.4% from 1 December – but in reality this is just a vague benchmark and there's no guarantee you'll win anything at all.

For full info on how they work, check out our Premium Bonds guide.

How will the Premium Bond changes affect me?

Here's a table of the typical prizes and how their distribution will change from 1 December:

Premium Bond Changes

Prize level Number of prizes per month Estimated number of prizes per month from December
£1 million 2 2
£100,000 3 4
£50,000 5 9
£25,000 12 18
£10,000 28 42
£5,000 57 87
£1,000 1,366 1,660
£500 4,098 4,980
£100 22,190 22,792
£50 22,190 22,792
£25 2,325,993 2,906,305

How will other NS&I products be affected?

Savings provider NS&I, which is backed by the Treasury, will also increase the rates of its variable savings products, by 0.25 percentage points. From 1 December, its Direct ISA and Income Bonds will pay 1%, its Direct Saver will pay 0.95%, its Investment Account 0.7% and Junior ISA 2.25%.

None of these rates is market-leading – the current best-buy cash ISA from the Post Office, for example, pays 1.07%. For more best buys, see Top Cash ISAs and Top Savings.