Here's exactly when to swap to your winter duvet, according to an expert

A young couple place frozen bed sheets on their mattress during the summer to help them sleep cooler
(Image credit: Getty)

With spring just around the corner, many of us in the UK are thinking about refreshing our sleep setup. But while warmer, brighter days are (hopefully) on the horizon, you might want to hold back on transitioning your best mattress to its summer bedding. 

James Higgins, CEO of Ethical Bedding, suggests that while the days might be getting warmer, cold nights mean it's worth sticking with your thicker duvet until 9th May. “Monitoring trends of temperatures at midnight in spring for the last five years," he says, "we observed a significant temperature increase happening in the second week of May."

“Examining the daily breakdown of May’s temperature at midnight, we worked out that May 9 is the average date which had consistently recurring higher temperatures," explains James. A few stuffy nights doesn't mean the best duvet right now is a lighter duvet – wait until those warm evenings are a little more frequent. Let's be honest, we all know there are likely to be some cold nights in the weeks ahead.

How to choose the right duvet tog rating

May 9th is the date James recommends switching a duvet with a winter tog rating for one with a summer tog rating, but let's break that down further. The tog rating system indicates how warm or cold you can expect a duvet to feel. Running from one to 15 – one being the coolest and 15 the warmest – tog ratings offer insight into just how cosy you'll be when tucked up under your duvet.

A woman in her bedroom, tidying sheets by the bed

(Image credit: Getty Images)

When changing for the summer temperatures, James recommends sticking to the lower end of the scale. “Opt for a summer tog duvet with a rating of 4.5 or less, which combats the high temperatures by allowing body heat to escape as you sleep," he suggests.

But while these cooler duvets are preferable on those warm summer nights, we all know that summer heat isn't always reliable. "If the weather isn’t quite so warm, a duvet rated between seven to nine tog may be more suitable," says James. This mid-range tog rating is best for fluctuating temperatures, and if you only have the budget (or storage space) for one duvet, it can work year-round. 

Right now, with the weather still lingering on the cooler side in most of the UK, a duvet with a tog rating between nine and 11.5 is best. Still warm, but not so thick as to become uncomfortable as we move into spring. Tog ratings of 13.5 or higher are ideal for very cold nights, when you want your bedding to keep you as toasty as possible.

If you struggle with night sweats, consider keeping a lower tog duvet on your bed throughout the year. In addition, the best cooling mattresses can help you maintain an even temperature, no matter the season.

A headshot of Ethical Bedding CEO James Higgins
James Higgins

James Higgins is a sleep expert and the CEO of Ethical Bedding, the UK's only B Corp accredited sustainable bedding company. James founded Ethical Bedding using his innate love of nature as a driving force, creating the most sustainable luxury bedding range with environmental prosperity at its heart.

Ruth Jones
Staff Writer

Ruth is TechRadar’s Sleep Writer. She’s here to help you find the perfect sleep setup for your budget and personal preferences. As well as keeping a keen eye on everything that’s going on in the world of mattresses, she regularly speaks to experts to help you learn how to improve your sleep habits, whether that’s by debunking sleep myths or explaining the science behind it all. Prior to joining the TechRadar team, she wrote features and product guides for new parents hoping to get a decent night's sleep, as well as writing for a variety of online spaces.