How to Sleep on a Long Flight, From Red-Eyes to 12-Hour Hauls

A red-eye from Los Angeles to New York spends about five hours in the air. Take away the climb and the descent and you have roughly four hours to sleep, ending at what your body still believes is 3:30 a.m.

So start with the clock. The neck pillow, the headphones and the mask all come later. (We sell one of those and will get to it.)

When should you sleep on a long flight?

Sleep when it's night at the place you're landing, whatever the cabin lights are doing. The CDC's travel health guide advises timing meals, sleep and light on a flight by your destination's clock, and that one rule gives you a different plan on every route.

Flight	What the clock says	Your plan
Coast-to-coast red-eye, about 5 hours	You land around 6:30 a.m. in New York, which feels like 3:30 a.m.	Eat before boarding, sleep as soon as you're in the air and schedule nothing important before noon
Overnight from the East Coast to Europe, about 7 hours	A 7 p.m. departure from New York is already midnight in London	Eat at the airport, skip dinner on board and sleep right after takeoff
Midday from the West Coast to Tokyo, 11 to 12 hours	You take off in Tokyo's early morning and land in its late afternoon	Nap for an hour or two early on, try to stay up after that and go to bed at Tokyo's bedtime
Any trip under about two days	Your body won't have time to adjust	The CDC's guide suggests staying on home time, so sleep when you'd sleep at home

What is the best seat for sleeping on a plane?

A window seat, for most people, because it gives your head something to lean on and nobody climbs over you at 2 a.m. The Sleep Foundation adds that seats near the wings may feel smoother. Stay clear of the galley and the bathrooms, and check a seat map for rows that don't recline.

The trade-off is getting up. The CDC cites research in which window seats carried about twice the risk of a blood clot on long flights, and about six times the risk for travelers with a BMI of 30 or higher. It says an aisle seat might be protective, probably because you're freer to move around. The overall risk is small, but if you have any of the risk factors listed below, take the aisle and give up the wall.

Do eye masks really work on planes?

They do, because a dimmed cabin is still a lit one. Someone's movie is flickering two rows up, and the person in 23C has picked 2 a.m. to start a novel. Light slows or halts your brain's production of melatonin, the sleep hormone, and as the Sleep Foundation points out, eyelids can't block enough of it.

Don't ask a mask for more than that. A 2023 study in the journal Sleep reported that a week of wearing one overnight improved learning and next-day alertness, but a reanalysis in the same journal that year argued the evidence was neither clear nor consistent. Wear one for the dark.

What matters most is the seal. Test your mask before you fly: put it on, look down and see whether light comes in at the bridge of your nose. It should stay put when you turn your head against the headrest, and it shouldn't press on your eyes.

The LS Silk sleep mask is 100% mulberry silk, shell and fill, in 22-momme, contoured to sit over your eyes without pressing on your lashes, with a silk-covered elastic band. The Deep Rest cocoon mask is wider, reaching toward the sides of your face, with an adjustable hook-and-loop closure at the back. There's more in the benefits of a silk eye mask.

What else helps you sleep on a plane?

Earplugs or noise-canceling headphones, warm layers, something to rest your head on and steady sips of water help most, and nearly all of it is free or cheap.

Cold. Cabins run cool and a blanket isn't a given, so wear layers and socks.

Your head. Recline if you can, and use a travel pillow or a rolled sweater against the wall. Long hair rides easier in a low, loose braid than in a high ponytail, which fights the headrest.

Dry air. Cabin air is usually 10 to 20 percent humidity, according to the CDC, which can dry out your eyes and upper airway. Sip water steadily, though not so much that your bladder wakes you, and take out your contact lenses: the CDC says to avoid sleeping in them unless your eye care provider has told you otherwise.

Caffeine. Its half-life is about five hours, so half of a 5 p.m. airport coffee is still with you at 10 p.m.

The seat belt. Buckle it over your blanket where the crew can see it, so nobody has to wake you when the sign comes on.

Should you drink alcohol or take melatonin to sleep on a flight?

Skip the nightcap, and talk to your doctor before you take anything. What follows is general information, and your own health history counts for more than any article.

Alcohol can help you drop off, then breaks up your sleep later, the CDC says. In a small 2024 study in the journal Thorax, healthy adults slept for four hours at simulated cabin pressure after about two beers or two glasses of wine. Their blood oxygen fell to a median of about 85 percent, against 88 percent without alcohol, and their heart rates rose to about 88 beats a minute, against 73. That doesn't show a drink on a plane is dangerous for a healthy person, but the researchers cautioned that more alcohol could intensify the effects, especially in older passengers and people with existing health conditions.

Melatonin may help with jet lag, according to the National Institutes of Health, but the CDC warns that taking it at the wrong time can leave your body clock further out of step. In the US it's sold as a dietary supplement, and tests have found some products don't contain what the label says. Anyone taking other medicines, and anyone pregnant or nursing, should check with a doctor first.

Sleeping pills and antihistamines. The CDC's guide says to avoid long-acting sedatives during a flight, and lists antihistamines, the active ingredient in many drugstore sleep aids, among the drugs to avoid for jet lag. If your doctor prescribes something for travel, ask about trying it at home first, and don't mix it with alcohol.

Is it safe to sleep through a long flight?

For most healthy people, yes, as long as you also move. Long flights carry a small risk of a blood clot, usually in the leg (deep vein thrombosis), and a long sleep means hours of sitting still. The CDC cites one study of flights over four hours that found 1 case per 4,656 passenger flights. Most cases happen in people with existing risk factors, such as a previous clot, recent surgery, pregnancy, estrogen use, cancer or obesity.

So when you wake up, stand, walk the aisle and flex your ankles before you settle again, which the CDC considers reasonable for anyone on a long flight. If any of those risk factors apply to you, ask your doctor before you fly, including about compression stockings. Most travel-related clots show up within a week or two, so see a doctor promptly for swelling, pain or redness in one leg, and get emergency help for sudden trouble breathing or chest pain.

See the silk sleep mask and the adjustable Deep Rest →

The wheels touch down in New York at 6:30. If it went well, you got three hours and change, in pieces, with your head against a plastic wall. Nobody would call that a good night's sleep. It will get you to lunch, though, and lunch is as far as a red-eye needs to take you.

Frequently asked questions

Can you get real sleep on a five-hour red-eye?

You can get some, usually about four hours at most once the climb and descent are taken out. Eat before you board and be ready to sleep soon after takeoff. Expect to feel short on sleep the next day, and keep the morning's plans light.

Should I sleep on the plane or stay awake to avoid jet lag?

Follow the clock at your destination. Sleep if it's night there, and if it's daytime there, limit yourself to a nap and go to bed at local bedtime. For trips under about two days, the CDC's guide suggests staying on home time.

Is it OK to take melatonin on a plane?

Melatonin may help with jet lag, but timing matters, and the CDC warns that taking it at the wrong time can push your body clock further off. It's sold as a dietary supplement in the US, so the amount can differ from the label. Ask your doctor first, especially if you take other medicines or are pregnant or nursing.

How long does jet lag last after a long flight?

It varies, but the CDC gives an average adjustment of about an hour a day after flying east and an hour and a half after flying west, so five hours ahead in London can take most of a week to clear. Daylight at your destination helps: generally, seek morning light after flying east, and after flying west, avoid bright early-morning light and get your daylight later in the day. Keep any nap on arrival short.

Is it bad to sleep for an entire long flight?

Not for most healthy people, but try not to stay still the whole way. The CDC considers frequent walking and calf exercises reasonable on long flights. If you've had a blood clot, recently had surgery, are pregnant or have other risk factors, ask your doctor before you fly.

Is a silk eye mask worth it on a plane?

It can be, if comfort over a long night matters to you. Any mask has to block the light and stay put, so check the seal at your nose before you fly. Silk is smooth and can feel gentle against the skin, and the LS Silk sleep mask is contoured to sit over your eyes without pressing on your lashes.

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