The single biggest mistake you can make when shopping for a mattress in the January sales – and expert advice on how to avoid it

A bedroom with a bed in front of a large sash window. The bed has white and orange pillows and a white duvet cover.

If you need to replace your mattress, there are two key times of year to shop for a better deal, and one of them is right now, in the extended Boxing Day and January sales.

However, discounted or not, a mattress is still a significant investment, and when prices are slashed, it can be easy to rush into a purchase that ends up being a big (and costly) mistake.