Some €1.2m in unclaimed prizes from winning prize bonds has built up over the past 50 years, with almost 10,000 bondholders not yet claiming their winnings.
The Prize Bond Company is today urging customers who may have moved house or who don't check their numbers regularly to get in contact.
Last year, over 145,000 prize bond holders shared a tax-free prize fund of €13.8m, and 1,750 prizes are won weekly by prize bond holders.
For prizes worth €250 or less, a cheque is sent out to the winner; and for any prizes worth more than €250, a form is enclosed for the investor to claim their prize. If the address is wrong, the cheque is never cashed.
The Prize Bond Company says some of the unclaimed prizes date back to the first days of the draw in 1957.
These prizes are placed on deposit and earn interest until they are claimed. They are held indefinitely until claimed by the bondholder.