I spend the majority of the year staying at hotels and vacation rentals. I’m generally quite good at picking properties that meet my fairly relaxed requirements. Every so often, though, I find myself at a property that despite advertising air conditioning, does not allow me to set the thermostat to a temperature I find comfortable for sleeping. With that in mind, I have done some research compiling the sleeping temperature recommended by the CDC along with other public health authorities and experts around the world.

U.S. Centers for Disease Control and Prevention (CDC)

Most major hotel chains including Marriott, Hilton, and Hyatt are headquartered in the United States. The others all maintain large operations in the United States. It makes sense, then, that the recommendations of the Centers for Disease Control and Prevention (CDC), America’s official public health agency, would be deferred to.

According to an article on the CDC website on optimizing sleep, the ideal sleeping temperature is between 65º to 68º F (18º to 20º C).

U.K. Government

Another major hotel chain (IHG) is headquartered in the United Kingdom. Let’s see what the recommendation is from that government.

While the U.K. doesn’t have a CDC equivalent per se, it does have the NHS (its public health system). According to a number of NHS websites such as this one, the ideal temperature for sleep is between 16º to 18º C (60º to 65º F).

The Lullaby Trust

Another major UK organization providing a sleep temperature recommendation is the Lullaby Trust, the UK’s leading charity focused on preventing sudden infant death syndrome (SIDS) and promoting infant health. While not for adults, the Lullaby Trust provides a fact sheet recommending a temperature of 16º to 20º C (60º to 68º F) for infant sleep.

A room temperature of 16–20⁰C is ideal for your baby, when growing up in the UK. This feels quite cold to a lot of people, so using a room thermometer can help check the temperature. If you are using light bedding such as sheets and blankets, they should be tucked in carefully with no loose ends that could obstruct your baby’s breathing. Similarly, baby sleeping bags should be well fitted, especially around the neck and arms, but comfortable, so your baby cannot wriggle down inside.

Cleveland Clinic

The Cleveland Clinic is one of the most respected hospitals in the United States on the cutting edge of medicine. The hospital provides a helpful resource on the best temperature for sleep in which it states that 60 to 67° F (15 to 19° C) is the best temperature for sleep.

The Clinic adds: “If your bedroom temperature is above 70° F (21º C), it’s too hot.”

Harvard

According to an article from Harvard Health Publishing: “Most people sleep better in a room that’s slightly cool. Keep room temperature around 65°F to 68° F at night.”

The National Sleep Foundation

The National Sleep Foundation published 10 tips for a better night’s sleep. One of them addresses the ideal temperature for sleep and like other experts and health authorities, they suggest sleeping with the thermostat set between 60 to 67° F (15º to 19° C).

Make sure your bedroom is cool. Your body temperature naturally decreases to initiate sleep. A bedroom temperature between 60 and 67 degrees Fahrenheit helps promote sleep.

Conclusion

While there’s some variation, the recommendations from experts and public health authorities are remarkably consistent. The ideal sleeping temperature is between 15º to 20º C (60º to 68º F). Warmer sleeping temperatures result in reduced sleep efficiency and are not advisable with a 2024 study by Italian and Swedish scientists finding that sleep efficiency degrades when sleep temperatures exceed 20º C (68º). Given that a good night’s sleep is the primary product being sold by hotels, it’s crucial that hotels provide air conditioners that can be set to optimize sleep.