- Dark ink-like dots in mattress seams that smear when wiped (droppings).
- Rusty red spots on sheets, pale shed skins, tiny white eggs.
- Live flat, reddish brown bugs the size of an apple seed.
- Bites in a line or cluster help, but some people never react to bites at all.
Bites alone cannot prove you have bed bugs. Plenty of people react to nothing, and plenty of itchy marks come from something else. The signs below are what pest controllers look for. If you find two or more, treat it as bed bugs and act tonight.
Do I have bed bugs? Free checker
Tick what you have noticed. Be honest; this is just for you.
The 7 signs of bed bugs
1. Rusty or red spots on the sheets
Small blood marks where a bug was squashed as you moved in your sleep. Usually near the pillow or where your arms and legs rest.
2. Dark dots like felt-tip pen
Bed bug droppings are digested blood. They look like dots from a fine felt-tip, often in clusters along seams and piping. Wipe one with damp kitchen roll: droppings smear reddish brown, dirt does not.
3. Shed skins
Young bed bugs moult five times before adulthood, leaving pale, see-through husks shaped like the bug.
4. Eggs and egg shells
About 1mm long, pearly white, often stuck in groups inside folds, stitching and cracks.
5. Live bugs
Adults are 5 to 7mm, flat, oval and reddish brown, and swell up and darken after feeding. Nymphs are smaller and paler. See what bed bugs look like at every stage.
6. A sweet, musty smell
Only noticeable with a heavier infestation. Not a sign to rely on.
7. Bites in a line or cluster
Bed bugs often bite several times in a row on skin exposed while sleeping. Bites can take hours or days to show and some people never react. Compare them in our bed bug bites guide.
The 10 minute mattress check
You need a torch, an old bank card and some white kitchen roll.
- Strip the bed under bright light and bag the bedding straight away.
- Torch along every seam, the piping round the edges, the label and the corners. Bed bugs live in edges, not the flat top.
- Slide the card into folds and stitching to flush out bugs, eggs and skins.
- Lift the mattress and check underneath, then the base, slats, headboard joints and screw holes.
- Wipe suspicious dots with damp kitchen roll to see if they smear.
- Check within 2 metres of the bed: bedside drawers, skirting boards, plug sockets, picture frames and curtain folds.
Where bed bugs hide
Bed bugs want to be close to you and out of the light. That is why the mattress seams are the number one spot, followed by divan bases and fabric bed frames, which are full of staples, folds and lining.
A smooth, sealed surface leaves them nowhere to go. That is the idea behind a full-zip mattress encasement and a sealed steel bed frame with no fabric or wooden joints.
If you find signs on the bed, read whether bed bugs live in pillows, duvets and bed frames next.
Signs it is probably not bed bugs
| What you notice | More likely |
|---|---|
| Itchy all over, worse in bed, no bugs or spots found | Dust mite allergy, especially with sneezing or eczema |
| Small fuzzy brown larvae near carpet edges or wardrobes | Carpet beetle larvae |
| Bites round the ankles, pets in the house | Fleas |
| Intense itch between fingers and wrists, worse at night | Scabies; see a pharmacist or GP |
Frequently asked questions
Can you see bed bugs with the naked eye?
Yes. Adults are about the size of an apple seed. Eggs and young nymphs are tiny and pale, so use a torch.
What time of night do bed bugs come out?
Mostly in the hours before dawn, when you are in deep sleep, but hungry bugs will feed at other times too.
Can you have bed bugs and not get bitten?
You can be bitten without reacting. Many people show no marks at all, which is why the physical signs matter more.
I found one bug. Does that mean an infestation?
Not always, but treat it seriously. One female can lay hundreds of eggs. Do the 10 minute check, wash bedding at 60°C and seal the mattress.
Found signs? Seal the mattress tonight
A full-zip encasement traps what is inside and stops new bugs moving in. Free next-day UK delivery on orders over £149.
Shop the bed bug encasement See the full planWritten by Richard Williams, founder of iDustMite, former NHS worker, guest speaker at the Allergy UK Show in 2025 and 2026, and adviser on over 1,000 one-to-one bedroom consultations. Reviewed October 2026.
