Charging your phone overnight on the bed? Fire services warn about this overheating risk and the safe spot you should use instead

Night-time routines often look the same. The light goes off, the phone goes on charge, and it lands somewhere on or in the bed. Under the pillow, tangled in the duvet, balanced on a cushion. It feels cosy, convenient and harmless.

UK fire services say it is not. Behind many “mysterious” bedroom fires, investigators find the same scene: a soft mattress or sofa, a trapped cable, and a phone that kept getting hotter with nowhere for the heat to go.

A charging phone needs air. A bed traps heat. That’s the difference between a normal night and a smouldering one.

You do not need to stop charging overnight. You do need to move your phone off the bed, out of the blankets, and onto a surface that lets it breathe.

Why fire services worry about your bedside habits

Across the UK, fire and rescue services repeatedly warn about phones, vapes, laptops and power banks left charging on beds, sofas and carpets. The pattern is the same: soft furnishings, damaged or cheap chargers, and devices that overheat quietly until something finally catches.

Lithium‑ion batteries are generally safe, but when they fail, they can fail hard. A fault, a crush, or consistent overheating can trigger “thermal runaway”: an internal chain reaction where the battery heats rapidly, vents gas and may ignite. On a firm, clear surface, you often spot the heat or smell before it spreads. In a pile of duvet, there is no early warning.

Firefighters do not see “freak accidents”. They see the same avoidable risks repeated in different bedrooms.

Most incidents start small: scorching on a mattress, melted plastic on a plug, black marks on a bedside table. The trouble is that they start when you are asleep.

What actually happens when your phone overheats

A phone on charge always generates some heat. Two things make that heat dangerous: lack of ventilation and extra strain.

• Lack of ventilation: Soft bedding and pillows wrap around the phone and cable. Heat gets trapped instead of escaping into the air. The temperature rises further, stressing the battery and the charger.
• Extra strain: Cheap or damaged chargers can push inconsistent current. Using the phone heavily while charging (gaming, long videos) adds extra load. Combined with trapped heat, the battery has to work harder in a warmer environment.

Modern phones have built‑in protections, but they are not magic. Software limits can reduce charging speed or shut things down; they cannot make a smothered battery cooler than its surroundings.

Protection systems help. A clear, stable surface helps more.

Over time, repeated overheating also weakens the battery. It may swell, crack its casing or become more prone to failure.

The worst places to leave a charging phone

Fire services consistently highlight a few spots as high‑risk. If these sound familiar, it is time to change where your phone sleeps.

• Under the pillow
  The classic danger zone. Body heat, trapped air and direct contact with fabric that can smoulder fast. Your head masks any early heat or smell.

• On or under the duvet
  Even if it looks “just on top”, the phone tends to sink into folds. The charger plug may also be buried where it connects, another hotspot.

• On sofas, armchairs and piles of clothes
  Cushions and throws behave like bedding. Phones slip down the side of the sofa, press against the charger, and stay hidden for hours.

• On thick carpets or rugs
  Carpet fibres insulate and can catch if a charger or cable overheats at the point of greatest resistance.

• Plugged into overloaded adaptors by the bed
  Tower adaptors or cheap multi‑plugs stacked with heaters, lamps, and multiple chargers push wiring and sockets to their limits.

Quick swap: from risky spots to safer ones

Risky place	Safer alternative
Under pillow or in bed	On a clear bedside table or chest of drawers
Sofa arm or between cushions	On a hard shelf or side table
Directly on thick carpet	On a saucer, coaster or hard tray on the floor
In a pile of clothes	On an uncovered desk or dresser

The main rule: hard, stable, uncovered, and away from anything that could easily burn.

The safer spot fire crews wish everyone used

Fire services are surprisingly simple about what they want you to do: move charging devices onto a firm, non‑flammable surface with space around them.

That can be:

• A bedside table or chest of drawers.
• A wooden or metal shelf.
• A hard tray, plate or coaster on the floor.
• A kitchen worktop, if you prefer to keep tech out of the bedroom.

Give your phone a flat, clear “parking space” where it can get warm without sharing heat with your bedding.

Aim to keep:

• A few centimetres of space around the phone.
• The charger brick visible, not buried behind furniture.
• Cables untangled and not pinched by drawers or bed frames.

If you like your phone nearby for alarms, place it at arm’s length-but not on the mattress.

Simple rules for night‑time charging

You do not need elaborate gadgets to stay safe. A handful of small habits cut the risk sharply.

Do:

• Use original or reputable chargers
  Look for genuine or certified brands, with proper markings and from trusted retailers.

• Check cables regularly
  Replace leads with frayed, bent or exposed wires. Damage often appears at the connector ends.

• Charge on a hard surface
  Bedside table, desk, coaster, shelf. Keep paper, tissues and clothes away from the charging area.

• Give sockets a break
  Unplug chargers when not in use. Spread high‑load appliances (heaters, hairdryers) across different sockets.

• Enable battery optimisation features
  Many phones now offer “optimised charging” or a cap at 80–90% to reduce battery stress overnight.

Avoid:

• Charging on beds, sofas or under pillows
  Even “just for a bit” can be enough if the device or cable is already compromised.

• Covering a device while it charges
  No stacking books, tablets or clothes on top; no tucking under the mattress edge.

• Using obviously fake or ultra‑cheap chargers
  These may skip essential safety components and quality checks.

• Sleeping with the phone in your hand on charge
  The cable can bend sharply, damage the connector and heat at a single stressed point.

• Leaving devices charging on top of laptops or games consoles
  Heat from one device adds to the other.

Treat chargers as small appliances, not background objects. You would not sleep with a hairdryer running under your pillow.

Extra risks: children, pets and power cuts

Some households face added layers of risk without realising.

• Children and teens
  Many charge phones, tablets and gaming devices on beds, often hidden under covers. Cables get twisted, chewed or crushed by laptops and controllers. A simple house rule-“no charging on beds or sofas”-protects more than one person at once.

• Pets
  Cats and dogs lie on warm spots and chew cables. A nibbled lead can spark or heat when power returns after being flexed.

• Power cuts and surges
  When electricity cuts out and then returns, there may be a surge. A damaged, poor‑quality charger plugged in on a bed or sofa is exactly where you do not want that sudden stress to land.

Storing a small, mains‑rated extension lead with an on/off switch near the bed can help. Keep it off overnight if you are not charging anything, and use it to gain socket reach without trailing leads under pillows or rugs.

Building a safer routine that actually sticks

Change works best when it feels simple and repeatable, not like a lecture you forget by next week.

• Pick a dedicated “charging spot” in each bedroom-a table, shelf or tray.
• Put a single, good‑quality charger there, not scattered around the room.
• Before lights out, move any devices off the bed or sofa, even if they are not on charge yet.
• Once a month, do a two‑minute check: feel for hot plugs, inspect cables, and clear clutter around sockets.

Two minutes of rearranging beats thirty minutes of smoke and sirens at 2 a.m.

FAQ:

• Is it safe to charge my phone overnight at all? Modern phones are designed to manage overnight charging, but safety depends on where and how you charge. Use a quality charger on a hard, clear surface and keep the area around it free of bedding and clutter.
  
• My phone gets warm when charging-is that normal? Slight warmth is normal, especially when the battery is low or you are using the phone. If it becomes hot to the touch or the charger is very hot, unplug it, let everything cool, and check the cable and plug for damage.
  
• Can I charge my phone on the floor? Yes, if the floor area is dry, away from where you might step on it, and preferably with the phone on a coaster, tray or small board rather than buried in carpet or under a rug.
  
• Are wireless chargers safer? They remove cable strain at the phone port, but they still create heat. The same rules apply: use reputable equipment, place it on a firm, ventilated surface, and never cover the phone or pad with fabric.
  
• How do I know if a charger is dodgy? Warning signs include missing or vague safety markings, very light weight, poor build quality, unusually cheap prices, or plugs that feel loose or spark when inserted. If in doubt, replace it with a branded or certified option.