A bus at 11. A motorbike at 1. The first delivery vans at 5, right when your sleep is lightest. If you live on a busy road, you probably tell yourself you are used to it by now. Your brain may have stopped waking you, but your body has not: research shows your heart keeps reacting to passing traffic long after you stop noticing it. The good news is that the fixes are well understood. Here they are, in the order that actually matters.

You Are Not Used to It

A 2014 review of the health effects of noise in The Lancet, led by sleep researcher Mathias Basner, set out what happens to a sleeping body on a noisy street.

Noise peaks as low as 33 decibels, roughly a soft whisper, can trigger reactions during sleep: a faster heartbeat, body movements, brief awakenings. And the heart's reactions fade with repeated exposure far less than the brain's do. Over time you may stop waking to the traffic. Your pulse keeps jumping anyway.

That is why "I sleep fine, I'm used to it" and "I wake up tired every day" can both be true. Researchers see these repeated night-time reactions as one likely route from long-term road noise to the higher rates of high blood pressure and heart disease found in people who live with it.

The same review makes a second point worth holding on to: whether noise disturbs you depends on the number of noise events and their character, not just the average level. A steady, distant hum can be easier to sleep through than a quieter street where a motorbike tears past every twenty minutes. It is the jump that wakes you.

How Loud Is Too Loud?

The World Health Organization's 2018 noise guidelines give a clear number. For sleep, road traffic noise at night should average below 45 decibels, measured outside the most exposed side of the building. Above that, it is linked to disturbed sleep.

A lot of people live above that line. The European Environment Agency's 2025 report found that road traffic exposes around 92 million Europeans to harmful levels, far more than rail or aircraft. Transport noise leaves an estimated 4.6 million with severe sleep disturbance.

You can look up your own number. In the EU and the UK, governments publish noise maps for major roads, usually with a separate night-time layer. Search your country's name plus "noise map" and find your street. If it sits above 45 at night, the problem is not your sensitivity. It is the road.

Start With Where You Sleep

The cheapest fix is often the biggest one.

Swedish research on homes along busy roads found that having access to a quiet side of the home cut noise disturbances by 30 to 50% on average. That was about the same benefit as turning the road itself down by 5 decibels.

  • Sleep on the quiet side. If any room faces away from the road, that is your bedroom. A smaller room at the back usually beats a bigger one at the front.
  • Move the bed away from the window. Put the headboard against an inside wall rather than the outside one. It is a small gain, but it is free.
  • Keep your head furthest from the road. If the bed can only go one way, sleep with your head at the end away from the window.

Then Deal With the Window

The window is the weakest part of any outside wall. One acoustics study measured road noise dropping by about 7 to 10 decibels through an open window, and by 26 to 30 decibels with the same window closed.

That difference of roughly 20 decibels matters more than it sounds. Every 10 decibels is heard as about half the loudness, so closing the window makes the traffic sound around a quarter as loud.

  • Close it at bedtime. If traffic is waking you, this is the single biggest thing you can do tonight.
  • Check the seals. Worn seals and gaps around the frame let sound straight through a closed window. Replacement seals are cheap.
  • Hang heavy, lined curtains. They take the edge off higher-pitched sound like tyre hiss. They do little for deep rumble, so treat them as a bonus.
  • Think about glazing for the long term. Secondary glazing or acoustic glass is the biggest upgrade if you own your home or can ask your landlord. Some cities subsidise insulation for homes on the noisiest roads, so ask your local council or municipality.

The summer problem. Closed windows and warm nights do not mix. Air the room out in the evening, then close up at bedtime. A fan moves air and adds a steady sound at the same time, and we cover the trade-offs in is it bad to sleep with a fan on?

Earplugs for the Loud Peaks

For loud, intermittent transport noise, earplugs have the strongest evidence of anything you can do in bed.

In a 2026 University of Pennsylvania sleep lab study, earplugs kept deep sleep and REM close to quiet-night levels when participants were exposed to aircraft noise. Pink noise played over the same aircraft noise did not. Traffic is not aircraft, but the problem has the same shape: loud peaks against a quieter night.

Two honest limits. Foam earplugs cut deep sound much less than high-pitched sound, so the rumble of a bus or lorry still comes through, for the same reason a neighbour's bass does: how to sleep with noisy neighbours. And not everyone can sleep with them, or should, if you need to hear an alarm or a child. How to use them well: is it bad to sleep with earplugs?

Where Sound Helps

Steady sound does not make traffic quieter. It makes each passing car a smaller jump. A van going past a silent room is a big step up from the background. The same van against soft, steady sound is a much smaller one. We explain that mechanism in why you cannot sleep without noise.

The evidence is small but relevant. A 2021 study followed 10 New Yorkers with noisy bedrooms and poor sleep. After a week with white noise, they spent less time awake during the night and reported falling asleep faster.

There is a caution too. In the same 2026 Penn study, pink noise played all night reduced REM sleep in people who were not used to sleeping with sound. Nobody knows yet whether that lasts. So use sound as the last layer, after the window, and keep it low: is white noise bad for you?

  • Match the sound to the traffic. Brighter sounds like white noise or steady rain cover tyre hiss and passing cars best. Deeper sounds like brown noise sit closer to engine rumble. Brown, white and pink noise compared goes into the difference.
  • Keep it just loud enough. You are shrinking the jump, not drowning the street. No sound at a sensible volume will cover a lorry braking outside, and it should not try.
  • Think about the early morning. Traffic does not stop at midnight. The build-up from around 5 AM lands in your lightest sleep, so a timer that ends at 1 AM leaves you unprotected when you need it most. If traffic is the problem, run your sound through the night, quietly. The full timer question is in why you wake up at 3 AM.

When Your Partner Sleeps Through It

Traffic splits couples in a very particular way. One of you sleeps straight through the night bus. The other hears every one.

Neither of you is imagining it. People genuinely differ in how easily noise gets through to a sleeping brain. The catch is that the usual fixes are shared: a fan or a sound machine fills the room, so the person who sleeps through traffic now has to sleep through your brown noise as well. How to keep your sound to yourself: how to sleep without disturbing your partner.

Where the Lullabar Fits

The Lullabar is a slim speaker that slides under your pillowcase. Sound travels through the pillow to the ear resting on it. Nothing goes in your ears, and at sleep volume, the person next to you hears nothing.

For traffic, it is the sound layer, not the window.

  • Your masking stays on your side. The partner who sleeps through traffic does not have to listen to your rain.
  • It can stay quiet. The sound starts at your ear rather than across the room, so it does not have to fill the room to reach you.
  • It lasts until morning. 10+ hours of battery covers the 5 AM rush, not just the first hour.
  • 11 nature sounds built in. They play without a phone. Noise colours stream over Bluetooth 5.4 or load onto a micro-SD card.
  • Built for a whole night. 11mm thick and 47.5 g.

The honest limit: it softens traffic rather than removing it. A lorry braking outside still breaks through, the same way a loud snorer does. For the loud peaks, the closed window and earplugs do more.

It is also clearest on your side, with your ear on the pillow. Lying on your back, you will need more volume to hear it.

How sound travels through a pillow: what pillow conduction audio actually is.

Common Questions

"Can you get used to traffic noise?"

Partly. You may stop waking to it, but a 2014 review in The Lancet found that the heart's reactions to night-time noise fade far less than the brain's. Noise peaks as low as 33 decibels can still speed up your heartbeat in sleep. So feeling used to it and waking up tired can both be true.

"How do I block out traffic noise at night?"

Work in order. Sleep on the side of the home away from the road. Close and seal the window, which in one study cut road noise by about 20 decibels more than leaving it open. Add earplugs for loud peaks. Then use low, steady sound to soften what is left. Secondary glazing is the long-term fix.

"Does white noise help with traffic noise?"

For moderate, intermittent traffic, yes. It makes each passing car a smaller jump from the background, and a small 2021 study found white noise reduced night waking in noisy New York bedrooms. It will not cover loud peaks: against loud transport noise in a 2026 lab study, earplugs protected sleep where pink noise did not. Keep the volume low.

"How loud is too loud for traffic noise at night?"

The World Health Organization recommends that road traffic noise at night averages below 45 decibels, measured outside the most exposed side of the building. Above that, it is linked to disturbed sleep. In the EU and the UK, public noise maps show the estimated night-time level for your street.

"Should I sleep with the window open or closed on a busy road?"

Closed, if traffic wakes you. One acoustics study measured about 7 to 10 decibels of reduction with the window open and 26 to 30 with it closed, which makes the traffic sound roughly a quarter as loud. Air the room out in the evening, or use a fan for airflow and steady sound.

The Bottom Line

Traffic noise is not something you should have to toughen up to. Your body keeps reacting long after you stop noticing, so it is worth fixing properly.

Fix the building first: the quiet side, a closed and sealed window. Add earplugs for the loud peaks. Then use low, steady sound to soften what is left, all the way through to the morning rush.

Try the Lullabar for 30 nights and give the 5 AM vans something softer to hide behind.