They bought the 137BG686951 Winning Bond in March 2008.

The second jackpot winner, who also gets £1million is from Wandsworth.

Their Winning Bond, 456RD476057, was purchased in May 2021.

The odds of winning per £1 Bond number are currently 21,000 to one.

Andrew Westhead, NS&I Retail Director, said: “Congratulations to our two £1 million jackpot winners from Dorset and Wandsworth – I hope they enjoy planning what to do with their new-found wealth.

“Premium Bonds are one of the nation’s favourite savings products, and a great way to start a savings habit with as little as £25.

“As well as the exciting prospect of winning the £1 million jackpot, there are also millions of other prizes up for grabs each month worth between £25 and £100,000, with a total prize pot this month of over £475million.”

This month, there were 91 winners who each scooped £100,000 and 182 people won a £50,000 payout each.

NS&I notifies Premium Bonds winners but sometimes it’s not possible to reach them.

For instance, if customers relocate or update their contact information without informing NS&I, they may not get the message.

This could lead to unclaimed prizes, particularly if the saver has opted to get prizes by cheque and they have moved without updating their details.

NS&I says choosing for prizes to be automatically paid into the winner’s bank account or reinvested into more Premium Bonds is the quickest way to get prizes, and more than 90 per cent of prizes are now paid this way.