A Taranaki woman has found over $400,000 at the bottom of her handbag in the form of an old Lotto ticket that she had forgotten to check.

The Lotto first division prize was sold in Hawera 10 weeks ago but the woman, who doesn't want to be named, didn't realise she was the missing winner.

It was only because her daughter asked her to check a couple of scratchies on a visit to town that she then thought to dig the old ticket out of her handbag.

"I was just blown away, I was just so shocked that I did not know what to think. It is hard to believe that I was carrying around $400,000 for all these weeks without knowing it," she said.

She had even come close to chucking it out, as she did not think it could actually be a winner.

She plans to use some of her winnings to pay off a mortgage and fund a New Year's celebration.

NZ Lotteries' current largest unclaimed prize is a $4.8 million Big Wednesday luxury prize package that was won on 17 November.

The Big Wednesday ticket was sold at Crandall Peters Paper Plus in Manukau.