Two Lotto players with tickets worth more than $600,000 and $85,500 are among big winners yet to claim their prizes.
The search is on for the winner of a Lotto First Division prize of $666,667 sold at Templeton Convenience Store in Christchurch for the draw on November 17 last year.
A Strike Four ticket worth $85,589 sold at United Video in Gore this year is also yet to be claimed.
The largest recent prize to expire unclaimed was a $3 million winning ticket sold in Masterton in early 2003.
Lotto players are being urged to check their tickets, which expire a year after the draw.
One Auckland winner in 2010 claimed his $509,937 prize just in time - one day before the one-year expiry date.
The Ponsonby man said he had put the ticket in a drawer at home and forgot about it until he saw it again by chance just before the deadline.
"It was a bit faded but I noticed the date on it and thought I'd better get down to the shop quick just in case I'd won anything,'' he said at the time.
Unclaimed Lotto prizes are transferred to the prize reserve fund, where they are used to fund jackpots and promotional prizes.
Players should also check the Winning Wheel serial number on their tickets as each spin is worth $100,000 to $1 million, and includes a weekend trip to wellington.
There are also six outstanding Winning Wheel winners. The tickets were sold at Fresh Choice Merivale, Christchurch; Royal Oak Mall Lotto, Auckland; Whitcoulls Cuba St, Wellington; Mangere East Post & More, Auckland; Parklands Dairy & Lotto, Auckland; and Countdown Dargaville.
The first ticket is set to expire in June.
While up to 3 per cent of all NZ Lotteries' prizes are unclaimed in an average year, hundreds of other players have had near misses when it came to claiming prizes.
The result of going through the washing machine damage, and chewed tickets by dogs and babies are among the most common damage, said a spokeswoman.
Others have gone to great lengths to protect a ticket after checking the numbers including putting it in a Bible, hiding it in their underwear and taping it to their body, she said.