Where do you put your phone at night? If you're like most, it's probably somewhere close by, either on the dresser next to your bed or beside your pillow. Every night, the habit is instinctual: you plug your phone in, tuck it nearby, and drift off with your alarm and your notifications within arm's reach. It's something you've likely done every night for years without giving it a second thought.
But there are real reasons to rethink where your phone spends the night. From fire risk to radiation exposure to the toll it takes on your rest, keeping your device close while you sleep comes with tradeoffs you might not have considered. Here's what you should know before you plug in tonight.
It Could Catch Fire
As you're probably already aware, lithium-ion batteries, the kind found in virtually every smartphone, can fail in ways that lead to overheating or even combustion. It's not a common occurrence, of course, but fire officials across North America have flagged it as a real and recurring risk, especially when a phone charges overnight, unsupervised, for hours at a stretch. Montreal fire officials have specifically urged people not to charge their phones overnight due to the potential fire risk this creates.
The danger multiplies when your phone is charging under a pillow or buried in bedding. Phones need air circulation to dissipate heat, and when you charge one on your bed or under a pillow, you're essentially wrapping it in insulation. Trapped heat can climb high enough to burn skin, melt plastic, or ignite fabric, which is exactly the scenario you're creating when your device is charging inches from your face for eight hours.
What makes this especially risky is that you're asleep while it's happening. You might think you'd definitely jolt awake as soon as a fire started, but that's not true: you can't smell smoke while you're sleeping, so if a fire starts, the smell won't be what wakes you up but a fire alarm. That's a pretty unsettling detail, since it means the usual early-warning signs of an electrical fire, like a burning smell or unusual sound, are far less likely to reach you in time.
Fire safety experts also point out that most people don't realize their phone is fully charged and still drawing power isn't the real hazard; it's the combination of a soft surface, poor ventilation, and hours of unattended charging that creates the danger. Most power bank and battery fires in recent years have happened overnight, while someone was asleep, and that pattern reflects the combination of long uninterrupted charging, bedding that traps heat, and battery cells that were already aging or damaged. The safest habit is charging your phone on a hard, open surface, ideally away from the bed entirely.
Radiation Risk
It's not just the battery, either. There's also a radiation risk. Smartphones communicate with cell towers using radiofrequency (RF) radiation, a form of non-ionizing energy that's different from the ionizing radiation found in X-rays. Yet, it's important to note that this type of radiation doesn't generally carry enough energy to break chemical bonds within the body or cause direct DNA damage, which is a crucial distinction when you're weighing how concerned to be.
But while currently available scientific evidence does not show a consistent connection between phone use and health problems, that hasn't stopped public health advocates from recommending caution, particularly for habits that put a phone close to your body for extended, uninterrupted periods. Ironically, that's exactly what happens when your phone sits by your head all night. Several advocacy and science organizations have petitioned the FDA on this issue and offer a straightforward recommendation: keep devices away from the body as much as possible, and don't sleep with your phone right by your head, such as under your pillow. It's a low-effort adjustment, and given that exposure decreases quickly as distance from the phone increases, moving your phone even a few feet away can meaningfully cut your exposure.
The distance factor matters more than most people assume. Since radiofrequency energy weakens rapidly over even short distances, the difference between having your phone under your pillow and having it across the room is significant, not marginal. Charging it on a dresser or desk rather than your nightstand costs you nothing in convenience but meaningfully reduces the amount of RF energy your body absorbs overnight.
It Disrupts the Sleep You're Trying to Get
Beyond fire risk and radiation, there's a more immediate problem with keeping your phone close: it actively interferes with your ability to fall and stay asleep. The blue light emitted by phone screens suppresses melatonin production, the hormone your body relies on to regulate its sleep-wake cycle. Even a brief glance at a notification can be enough to reset that process and delay when you actually drift off.
Then there's the matter of notifications themselves. A buzz, a chime, or even the glow of a lock screen lighting up in a dark room is enough to pull you out of deep sleep or prevent you from reaching it in the first place. And since it's within reach, just on your dresser or under your pillow, the temptation to check your phone "one more time" or to engage in late-night scrolling gets far stronger. Over time, these repeated micro-interruptions add up, leaving you groggier in the morning even if you technically spent eight hours in bed.
The bottom line is this: if you're used to sleeping with your phone by your side, let this be a sign that you should break the habit. You might think the risks above, especially fire and radiation, won't happen to you, but if it does happen it'll be too late. No one says you need to give up your phone entirely, but if you're heading to bed anyway, it's best to put it out of reach so you can get the rest you actually need.
