Why you sleep badly in a new place

Key takeaways

• The first night somewhere new is usually the worst. Sleep researchers call it the first-night effect, and sleep labs have measured it since 1966.

• In a 53-study review of healthy people, night 1 had longer sleep onset, more waking, less total sleep, and less REM than night 2. The gap between night 2 and night 3 was small.

• One side of the brain sleeps lighter. In one lab study, the left side of a brain network stayed more responsive to odd sounds on night 1, but both sides still slept.

• Hotel-specific evidence is thin. No trial shows that a particular pillow, scent, or room tweak fixes the first night.

• A second night helps, even a week later. In lab studies, the later night was still better than the first.

What the first-night effect is

Agnew, Webb, and Williams first described the first-night effect in 1966, when volunteers sleeping in a lab slept worse on their first night than on later ones. The pattern has shown up in studies ever since. A meta-analysis of 53 studies covering 1,422 healthy people compared sleep on the first and second nights in a lab. On night 1, people took longer to fall asleep, woke more after drifting off, slept less in total, and spent less time in REM sleep and more in light sleep. Deep sleep, sleep apnea, and leg movements didn’t differ.

The studies were lab-based, so the review doesn’t measure hotels directly. It also found the effect wasn’t equal for everyone. Adults aged 20 to 29 showed the least of it, and the gap between the second and third nights was small, which suggests the effect is mostly a night 1 problem.

Does half your brain stay awake?

The popular idea is that half the brain stays on guard in a strange bed. It comes from a 2016 study in Current Biology of 35 young adults, which we describe in our guide to sleeping well on a trip. On night 1, a network on the left side of the brain slept lighter than the same network on the right, and it reacted more strongly to odd beeps played during sleep. Neither effect showed up on night 2. The National Institutes of Health and the National Science Foundation funded the work.

In humans, both sides of the brain still sleep, and one side sleeps lighter. Dolphins and some birds do sleep with one hemisphere at a time, which isn’t the same thing. A 2024 study in Sleep of 45 and 30 healthy adults, funded by the European Research Council, didn’t find the same link between the brain asymmetry and the first-night effect. The brain-on-watch explanation remains a hypothesis.

How long does it last?

In most lab studies, mainly the first night. In the 2024 study, the two lab nights were a week apart, and the first night was still the worse one, so the second night was better even after a week’s gap. People in that study also slept worse on their first night at home when they were wired up for recording, so some of the disturbance may come from the recording equipment. These were lab nights, not hotel stays.

Does the room matter?

A survey of 505 hotel guests in 28 hotels found that morning types, people sensitive to their sleep environment, and people whose trip cut their sleep short were most affected, and that business travelers had more disturbed sleep than leisure travelers. Guests who were more satisfied with their hotel were less likely to have insomnia there, and some people who had insomnia at home slept better on the road. The survey was self-reported and can’t show cause.

What about insomnia?

The evidence points in two directions. A meta-analysis of seven studies with 639 people with insomnia and 171 healthy controls found that people with insomnia show a first-night effect too, with a somewhat different profile. A single 2024 study of 39 patients and 35 controls found that patients changed less between nights than the controls did. Neither study looked at travel, so it isn’t clear whether new places make insomnia better or worse. If sleep problems last for weeks, a doctor is the right person to ask.

What helps

The research on fixes is thin. No trial has tested whether bringing your own pillow or bedding helps on the first night, and no study shows that a hotel room tweak does either. The closest result is a randomized crossover study of 155 people, which found that a partner’s scent raised sleep efficiency measured by a wrist sensor by about 2%. It wasn’t a travel study, so it says little about hotels.

The National Heart, Lung, and Blood Institute recommends a quiet, cool, dark bedroom, a regular schedule, and time outside every day. In a hotel, that can mean asking for a quieter room, switching off or covering the lights on the room’s electronics, and setting the thermostat before bed. We cover related ground in our guides to white noise, earplugs, and blackout shades. If you’ve crossed time zones, our jet lag guide deals with the clock problem.

Because the effect fades by the second night, a bad first night isn’t a reason to worry. Plan around it, for example by not scheduling an important early morning right after you arrive.

The short version

The first-night effect is real, well measured in labs, and usually gone after one night. No study shows that any particular hotel trick fixes it, so expect night 2 to be better.

Frequently asked questions

Why can’t I sleep the first night in a new place?

It’s called the first-night effect. A 53-study review of healthy people found that night 1 brought longer sleep onset, more waking, less total sleep, and less REM than night 2. One lab study found part of the brain slept lighter and reacted more to odd sounds, though that doesn’t prove cause.

Does it go away on the second night?

In most lab studies, mostly yes. The difference between nights 2 and 3 was small in the 53-study review, and a 2024 study found the second night was better even when it came a week later.

Is it only the room?

No. The 2024 study found disturbed first-night sleep at home when people were wired up for recording, and a survey of 505 hotel guests found that business travelers, morning types, and people sensitive to their sleep environment were more affected.

Do people with insomnia sleep worse in a new place?

The evidence is mixed. One meta-analysis found they show a first-night effect, and one 2024 study found they changed less than healthy controls. Ask a doctor if poor sleep continues.

Does bringing my own pillow help?

No trial has tested it. A partner’s scent raised sleep efficiency by about 2% in one study that wasn’t about travel. It’s harmless to try, and the evidence for it is indirect.