How to Sleep Cooler: 10 Things to Try Tonight

Start with the obvious. If your bedroom is uncomfortably warm, lower the thermostat or otherwise cool the room before trying to engineer around the problem with your bed.

Don't worry about achieving exactly 65°F. Research shows meaningful individual variation in thermal comfort and sleep. Instead ask: Am I waking because I'm hot? If yes, try somewhat cooler.[2]

Bedrooms can retain heat from the day. When outdoor conditions make it appropriate, ventilation can help exchange warmer indoor air for cooler outside air. Air conditioning can cool the room directly.

The goal is simple: don't climb into an overheated bedroom and expect your sheets to solve the problem.

Air movement can increase heat transfer and evaporation, making warm conditions feel more comfortable. A fan is inexpensive and easy to test.

During dangerous extreme heat, however, don't assume a fan alone provides adequate protection. Heat safety depends on temperature, humidity, age and health.

This may be the highest-return change on this list. If you're underneath a top sheet, blanket and heavy duvet, try removing a layer for several nights.

Your bedding creates an insulating microclimate around your body. Changing that microclimate may matter more than lowering the temperature of your entire house another few degrees.

Don't get trapped by marketing labels. “Cooling,” “performance,” “temperature regulating” and “breathable” don't guarantee better sleep. Material, weave, weight, moisture transport and the surrounding temperature all matter.

A systematic review found that bedding and sleepwear fibers can affect thermal comfort and some sleep outcomes, but the evidence is limited and doesn't identify one universally superior material. Experiment and judge the result by whether you feel cooler and remain comfortable.[3]

People usually think about blankets when they're hot. Don't forget the other side.

Your mattress, topper and mattress protector all contribute to the thermal environment around your body. If you feel heat building underneath you rather than primarily above you, the sleep surface deserves attention.

Before replacing a mattress, test simpler variables.

Not literally. Start with separate blankets. It's one of the simplest solutions for couples with different temperature preferences. One person can sleep under a light blanket while the other uses something heavier.

If that doesn't solve the problem, dual-zone bed technology can provide more individualized temperature control.

If you regularly wake hot, look beyond the bedroom. Alcohol, illness, stress, hormonal changes and certain medications can all influence nighttime warmth or sweating.

Keep a simple one-week log: bedroom temperature, alcohol, exercise, bedding, wake-ups and hot/cold sensation. Patterns often become easier to spot when they're written down.

If the simple changes aren't enough, powered airflow is one way to actively change the bed microclimate.

Systems such as BedJet direct air into the bed rather than cooling the mattress surface itself. This may appeal to sleepers who feel hot or sweaty under the covers but don't want a water-circulating mattress cover.

If you've worked through the simpler steps and temperature remains a major problem, active mattress-cover systems may be worth considering. These circulate temperature-controlled water through a cover positioned on the mattress, allowing much more direct control over the sleep surface.

The technology clearly changes the thermal environment. Whether that translates into objectively better sleep for a particular person is less certain. A 2024 systematic review and meta-analysis found that cooling bedding interventions did not consistently improve common objective sleep measures, and the certainty of evidence was low to very low. A more recent randomized crossover study of a temperature-controlled mattress cover found a substantial improvement in perceived sleep quality and thermal comfort, but no significant differences in objective sleep or biometric measures.

That's an important distinction. Feeling more comfortable matters. But it isn't the same thing as proving that a device improves every measure of sleep.[4][5]