The National Lottery has appealed for players to search "in the pockets of clothing, in wallets, bags and down the back of the sofa" as a ticket worth £1 million remains unclaimed.
The EuroMillions UK Millionaire Maker ticket was bought for the draw on April 26 and the lucky winner has until October 23 to claim the life-changing prize.
The winning code on April 26 was XFGV 45262.
If no-one comes forward, the prize money, plus all the interest it has generated, will go to help National Lottery-funded projects across the UK.
Andy Carter, Senior Winners’ Advisor at The National Lottery, said: "We’re desperate to find this mystery ticket-holder and unite them with their winnings, this amazing prize could really make a massive difference to somebody’s life.