What bed bugs on a mattress look like
Look for the signs before the insects: small dark spots along the seams are far more visible than the bugs themselves.
What to look for first
Small dark spots, like ink dots, along the mattress seams and piping. These are digested blood and are the most reliable early sign.
Also: tiny pale shed skins, and in heavier infestations a sweet musty smell.
What the insects look like
Adults are about 5mm long, roughly the size and shape of an apple pip: flat, oval and reddish brown. After feeding they become swollen and darker red.
Young bugs (nymphs) are much smaller and translucent, which is why infestations are missed early.
Eggs are about 1mm, pearly white, and usually laid in clusters in crevices.
They do not fly and do not jump. They move surprisingly quickly and avoid light, which is why daytime inspection finds signs rather than insects.
Where to look
They hide within a few feet of where people sleep, in crevices rather than open surfaces.
Mattress seams, piping and labels. The first place to check, and where the dark spots appear.
The bed frame and slats, particularly joints, bolt holes and where the headboard meets the frame.
Behind the headboard and along skirting boards behind the bed.
The divan base, including the underside and inside drawers.
Use a torch and, if you can, a thin card or old bank card to run along seams. Check the mattress on both faces and stand it up to see the underside.
Bites are the least reliable evidence
People usually notice bites first and they are not diagnostic, which is why identifying the signs matters.
Bites are typically small, red and itchy, often in a line or cluster on skin exposed during sleep. Reactions vary enormously: some people react strongly, and some do not react at all and have no idea they are being bitten.
They look much like fleas, mosquitoes, scabies or an allergic reaction. Do not conclude from bites alone, and do not conclude there is no problem because one person in the bed is unmarked.
Bed bugs are not known to transmit disease. The main effects are itching, disrupted sleep and, for many people, considerable distress. A pharmacist can advise on itching; see a GP if bites become infected.
Commonly mistaken for bed bugs
| Looks like | How to tell |
|---|---|
| Carpet beetle larvae | Hairy and bristly, found in carpets and wardrobes rather than mattress seams |
| Fleas | Jump. Bites usually around ankles and lower legs. |
| Dust mites | Microscopic. Cause allergy symptoms, not bites or visible spots. |
| Mould spotting | Does not smear when wiped with a damp cloth; digested blood does |
| Scabies | Intense itching worse at night, often between fingers. A GP matter. |
What actually works
This needs professional treatment
Bed bugs are very difficult to eliminate with shop-bought products. Contact your local council or a professional pest controller. Many councils offer a treatment service.
Partial DIY treatment frequently spreads them to other rooms, which makes the job harder and dearer.
What helps alongside professional treatment:
Wash bedding at 60 degrees and tumble dry hot. Heat kills them at all life stages.
A zipped mattress encasement, left on for at least a year, traps any remaining bugs inside and stops new ones establishing in the seams.
Do not throw the mattress out immediately. It rarely solves it, they will be in the frame and skirting too, and a discarded mattress can spread them.
Do not move to another room to sleep. They follow the host, which spreads the infestation.
Reduce clutter around the bed, which removes hiding places and makes treatment more effective.
Avoiding them
They are brought in rather than generated by poor hygiene, and a clean home is not protection.
When travelling, check the bed before unpacking, and keep luggage off the floor and bed, ideally on a rack.
Inspect second-hand furniture carefully, particularly beds, frames and upholstered items.
Use a mattress encasement if you are concerned, which makes inspection far easier because the seams are smooth.
Related reading
Other bedroom pests
Protection
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Questions people ask
What do bed bugs look like on a mattress?
Adults are about 5mm long, flat, oval and reddish brown, like an apple pip. The more visible sign is small dark spots like ink dots along the seams and piping, which are digested blood.
Where do bed bugs hide on a bed?
In crevices rather than open surfaces: mattress seams, piping and labels, bed frame joints and bolt holes, behind the headboard, along skirting behind the bed, and inside divan bases and drawers.
Can you identify bed bugs from bites?
No. Reactions vary enormously, some people do not react at all, and bites look much like fleas, mosquitoes or an allergic reaction. Look for the physical signs along the seams instead.
How do you get rid of bed bugs?
Professional treatment through your local council or a pest controller. Shop-bought products rarely eliminate them and partial treatment spreads them. Wash bedding at 60 degrees, tumble dry hot, and use a zipped encasement.
Should I throw my mattress away if I have bed bugs?
Usually not. It rarely solves the problem because they will also be in the frame and skirting, and a discarded mattress can spread them.