Santa has a 'naughty or nice' list, and this year so does Consumer NZ.

But rather than tracking your kids' behaviour through the year, the latter has been analysing the small print on various retailers' gift cards.

"Based on the complaints we've received over the years, gift cards seem to act more like a gift to retailers than to ourselves or others," says Gemma Rasmussen, Consumer head of research and advocacy.

More than $10 million spent on gift cards was lost every year, according to the watchdog's latest estimate - retailers pocketing the value left on expired cards.

"One in four gift card holders end up stuck with a card they can't use because either the card has expired or the retailer's gone bust.

"And more than half of gift card holders unable to redeem their voucher still had more than $20 unspent."

The real Christmas gift was to retailers, she said, rather than our loved ones.

"Half of gift card users experience problems using their card - from checking their balance to only being able to use their card at limited stores and, crucially, finding something to buy.

"We don't think it's fair that retailers can pocket your money without providing something in return.

"We have been calling for gift cards to be valid for a minimum of five years, which aligns with what shoppers in the US are entitled to."

The true amount lost was difficult to establish, with few retailers publishing data on expired gift cards, says Consumer NZ.

The $10m estimate was based on the few retailers that did, with non-redemption rates typically between 5 and 10 per cent.

Parliament is currently considering a bill from National's Melissa Lee that would require gift cards to last at least three years before they expire.

The Fair Trading (Gift Card Expiry) Amendment Bill passed its first reading in August.

If you are not sure what to buy someone and want to avoid buying a dud gift card, there is an option that not only has no expiry date, it can be used everywhere - without exception.

"Unless the retailer offers a fair redemption period, we recommend gifting cash,"says Rasmussen.

"Not only is it nostalgic, there are no strings attached."