Droppings
Rat droppings are dark brown, capsule-shaped and about 12 to 18 mm long, roughly the size of a large grain of rice or bigger. They are usually found in groups along walls, behind bins, in lofts and under sinks. Fresh droppings are shiny and soft; old ones are dull and crumbly. See our droppings guide.
Noises
Scratching, scurrying or gnawing in walls, ceilings, under floors or in the loft, especially at night, is a classic sign. Rats are heavier than mice, so the sounds are often described as thumping or dragging rather than light pattering.
Gnaw marks
Rats gnaw constantly to keep their teeth worn down. Look for fresh, pale gnaw marks on skirting boards, doors, plastic pipes, cables and food packaging. Gnaw marks about 3 to 4 mm wide point to rats; mouse marks are much finer.
Rub marks and runs
Rats follow the same routes every night. The grease and dirt in their fur leave dark smears along walls, pipes and joists, and outdoors they wear flattened runs through grass and along fences.
Burrows
In gardens, rats dig burrows about 6 to 9 cm across under sheds, decking, patios, compost bins and beside walls and drains. Active burrows have smooth, packed entrances with no cobwebs.
Smell
A strong, stale, ammonia-like smell in a loft, cupboard or under floors can indicate rats. A sudden bad smell later on may mean a rat has died in a void.
Other clues
- Pets, especially dogs and cats, staring at or pawing a wall or cupboard
- Bird food, pet food or fallen fruit disappearing overnight
- Shredded paper, insulation or fabric used for nests
- Holes around pipes or broken air bricks
What to do next
If you see any of these signs indoors, act quickly. Rats breed fast and cause damage to cables, pipes and insulation. Read about our rat control service or book a visit.
Questions and answers
Can you have rats without seeing them?
Yes. Most people never see the rats; they find droppings, hear noises or notice a smell first.
Is one rat a sign of more?
Often. Rats live in groups, so a single sighting usually means others nearby.
Are rats more active at certain times of year?
They are active all year, but they move indoors more in autumn and winter when food outside is scarcer.
Related pages
This page is general information, last reviewed on 19 October 2026. It is not a substitute for an on-site inspection.