What the numbers show
City of Toronto data shows rodent-related service requests rose from 1,165 in 2015 to 2,523 in 2024. A 2025 study of 16 cities ranked Toronto third for growth in rat numbers, and in July 2025 a rat response plan went to City Hall for debate.
Why rats are on the rise
- Warmer winters. Fewer hard freezes mean more rats survive the winter and breed earlier in spring.
- Construction. Digging for transit lines, condos and infill housing disturbs established colonies, which move into neighbouring yards, garages and basements.
- More people, more food. Garbage, compost and pet food give rats a reliable food supply.
Signs you have rats, not mice
- Droppings about 1 to 2 cm long (mouse droppings are the size of a grain of rice)
- Burrows along the foundation, under decks, sheds or patio stones
- Gnaw marks on wood, plastic bins or wiring
- Greasy rub marks along walls and gaps
- Noise in walls or ceilings, often heavier than mice
How to keep rats out
- Seal gaps larger than a quarter. Rats can squeeze through a hole the size of a toonie; mice through one the width of a pencil.
- Secure garbage and compost in bins with tight lids. Replace chewed bins.
- Remove bird feeder spill and fallen fruit, which feed rats every night.
- Clear clutter along fences and foundations where rats can hide.
- Fix leaks. Rats need water as well as food.
When to call a professional
If you see burrows, daytime activity or droppings in more than one place, the colony is already established. A licensed technician can place tamper-resistant exterior stations, treat burrows, and seal the gaps rats are using, then come back to confirm activity has stopped.