House Mice

How to identify house mice

Small, 2.5–4 inches in body with a tail nearly as long, gray to light brown, with large ears and pointed nose. You'll usually notice the signs first: rice-grain-sized dark droppings, gnaw marks, scratching in walls or ceilings at night, and a faint musky odor.

Behavior & biology

A female house mouse can produce a new litter roughly every three weeks and breeds all year indoors, so a few mice become an infestation fast. They're curious and constantly explore, nest near food and warmth, and need very little — they can enter through a gap the width of a pencil and survive on crumbs.

Why house mice matter

Mice contaminate far more food than they eat with urine and droppings, spread bacteria across kitchen surfaces, and gnaw constantly — including on electrical wiring, where they're a recognized house-fire risk. Their droppings and dander can also trigger allergies and asthma.

DIY vs. professional control

Snap traps and poison reduce numbers but never address how the mice are getting in, so the problem returns. Poison can also leave mice to die inside walls. Professional control is exclusion-first: find and seal every entry point, then trap and remove the active population and clean up contamination.

How Definity treats house mice

Definity solves mouse problems by sealing entry points with rodent-proof materials first, then trapping and removing the active population and cleaning contaminated areas. The exclusion work is the part that lasts — without it, you're just managing a recurring problem instead of ending it.