Rats are the pest people are most reluctant to admit they have. They carry a stigma that makes homeowners hesitant to act — and that hesitation is exactly what allows a small problem to become a serious one. The faster you identify a rat problem, the cheaper and easier pest removal becomes.
Here's what to look for, what it means, and what to do about it.
The Most Common Signs of Rats in a Property
Droppings
Rat droppings are the most reliable indicator. They are dark brown, roughly the size and shape of a large olive stone (about 10–15mm long), and tapered at one end. Fresh droppings are soft and dark; older ones become hard and grey.
Where you find droppings matters. A concentration of droppings in one area — behind a fridge, under kitchen units, along a wall — indicates a regular run or a nesting site nearby. Scattered droppings across a wider area suggest rats are moving through your property rather than nesting in it, which is a different problem requiring a different approach.
Gnaw Marks
Rats' teeth grow continuously, so they gnaw constantly to keep them worn down. Look for gnaw marks on:
- Wooden skirting boards and joists
- Plastic pipes and cable insulation (a serious fire risk)
- Food packaging — even thick cardboard and plastic containers
- Door frames and structural timbers
Fresh gnaw marks are pale and rough-edged. Older marks will have darkened with age. If you're finding new pale marks regularly, rats are actively present.
Runs and Smear Marks
Rats are neophobic — they distrust open spaces and stick to the same routes, typically along walls and behind objects. Over time, the grease and dirt on their fur leaves a dark smear mark along their regular paths. You may also notice flattened vegetation or worn tracks in gardens, particularly along fence lines and near compost heaps or outbuildings.
Sounds
Scratching, scurrying, and squeaking sounds — particularly at night — are a strong indicator of rats in wall cavities, under floorboards, or in loft spaces. Rats are primarily nocturnal, so sounds that emerge after dark are especially significant. If you're hearing regular movement above a ground floor ceiling, rats in the loft are the most likely explanation.
Burrows
In gardens, rats burrow into soil — particularly near food sources like compost heaps, chicken coops, vegetable patches, or beneath sheds and decking. Rat burrows are roughly 6–9cm in diameter with a clean, round entrance and a fan of freshly excavated soil nearby. Active burrows will have smooth, worn entrances; abandoned ones may be partially collapsed or blocked with debris.
Nests
Rats build nests from shredded soft material — insulation, cardboard, fabric, paper. Finding a nest in a loft, under floorboards, or in a rarely-opened cupboard is unambiguous evidence of an established presence. A nest with young rats means the problem has been ongoing for at least several weeks.
When Should You Not Be Calm?
Any rat sighting warrants action, but these signs indicate a more serious situation requiring urgent professional pest removal:
- Multiple nests found in different areas of the property
- Gnaw marks on electrical cables (immediate fire risk — contact a pest controller and an electrician)
- Evidence in a commercial kitchen, food storage area, or healthcare setting
- Signs of rats near young children's play areas
- A burrow system beneath a property's foundations
In these situations, DIY approaches are not adequate. The scale and risk require a professional with the right baiting strategy, access to professional-grade rodenticides, and the knowledge to identify and seal entry points.
Should You Try DIY First?
For a suspected early-stage problem — a few droppings, no confirmed nest, no gnaw marks on cables — a DIY approach using snap traps is reasonable as a first step. Snap traps are more humane and more effective than poison for isolated incidents, and they give you direct confirmation of what you're dealing with.
However, DIY has clear limits. If you've set traps for two weeks and are still seeing fresh signs, or if you've identified gnaw marks on cables, a nest, or multiple active burrows, professional pest removal help is not optional — it's necessary. Rats reproduce extremely rapidly: a pair can produce up to 200 offspring in a single year under ideal conditions. An untreated problem compounds quickly.
Finding a Pest Controller in London
If you're in London, PestPro Index lists qualified rat control specialists across all 33 boroughs. Every provider is listed with their genuine Google rating and review count — no sponsored rankings, no lead fees. Search by borough to find a local specialist who can assess the situation in person.
Summary
The key signs of a rat problem are droppings, gnaw marks, smear marks, nocturnal sounds, burrows, and nests. Act on any of these promptly — rats don't resolve themselves, and delay costs money. For early-stage problems, traps are a reasonable starting point. For anything beyond that, call a professional pest removal specialist.