The organisers of monthly Premium Bond draws are urging people to check whether they could be sitting on a surprise windfall.

There’s nearly £1 million worth of unclaimed prizes recorded against bonds registered to Hertfordshire people.

Most relate to small wins, but one man has failed to claim a £5,000 prize after his number came up seven years ago.

You can use the fee-free Premium Bonds Prize Checker to track unclaimed prizes that can be claimed from as far back as 1957 – there are Herts prizes for £25 dating back to 1962 still unclaimed.

The prize checker is on the home page of the nsandi.com website, but you need to know your bond number.