We've crunched the energy cost numbers and compared the pros and cons of hot water bottles, electric blankets and heated throws.
Our top 10 reveals which ones heat quickly and how much they cost to runShould you buy a hot water bottle?
Cost to buy: Cost to run: *Based on an initial cost of less than 5.4p to boil a kettle with enough water to fill a hot water bottle, then using the hot water bottle for three hoursPros:You might think that a kettle uses a lot of energy, but you'll actually use less energy if you use a kettle to fill your hot water bottle than you'd use to run an electric blanket or heated throw. That's as long as you only boil as much water as you need. Most manufacturers recommend only filling your hot water bottle to two thirds of their capacity.
A hot water bottle might not keep you warm throughout the whole night, though. Our tip, from testing various types of hot water bottle, is to spend more on a thicker cover rather than splashing out on an expensive bottle.
It's also important to wait for the boiling water to cool for at least five minutes before pouring it in. Boiling water will degrade the inside of the hot water bottle, leading to a much higher chance of the bottle bursting while you're using it.
Should you buy an electric blanket?
Cost to buy: Cost to run: Pros:Electric blankets are designed to be fitted to your mattress underneath your sheet, so your bed should feel the same as usual but with extra heat coming up from underneath you.
That's if you get a good one. Our tests found some electric blankets that distribute heat unevenly and have annoying wires you can feel through your bedsheet.
Electric blankets can cost more than £100, so it's worth doing your research first to avoid paying out more for a less-than-satisfactory night's sleep.
Should you buy a heated throw?
Cost to buy: Cost to run: Pros:A heated throw's main job is keeping you warm and snuggly while you're relaxing on the sofa, but you can also use them as a heated top blanket for your bed. You can lay the throw either on top of your duvet, or between your duvet and you.
Our energy-use tests found that electric throws cost less to run per hour than some electric blankets, but still cost more than boiling water for a hot water bottle.
You might find it a bit stuffy in your bed with an extra heated layer on top, though, and some throws have short cables that might not reach from the power socket to your bed. We also found some throws uncomfortable, as you can feel the wires running through them.
What's best and cheapest for keeping warm in bed?
Hot water bottles have the cheapest upfront and associated energy costs but, if you can afford it, we think a high-quality heated blanket is the best option for a cosy night's sleep.
If one of the best heated blankets is fitted below your bedsheet, you won't even know it's there, and it will gently spread warmth throughout your bed for as long as you need it to.
Why you shouldn't use an electric heater while you sleep
Electric heaters have been flying off the shelves since last autumn as an alternative to central heating. You can point the heater directly towards you for maximum warmth.
Inspiring tips for improving the place you live in: undefinedsource https://www.which.co.uk/news/article/the-cheapest-way-to-keep-warm-in-bed-alwIf3N5e4G5