What city has the most rats and mice in the US?

Key takeaways

• Rodents can cause severe damage to properties by chewing on wires and insulation. They also pose serious health risks and carry several diseases. 
• Western Exterminator identified some of the cities with the most rats, including Los Angeles, Santa Rosa, San Jose, Portland, Reno, and Seattle. 
• Human activity and rising temperatures have caused rodent populations to increase in urban areas. 
• Signs of a rodent infestation include droppings, strange noises, foul odors, gnaw marks, nesting materials, and tracks.

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Which city has the most rats and mice on the West Coast?

Why do these West Coast cities have the most rodents?

Are rodents in my home?

Preventing rodents in your home

Protect your home from rodents with Western Exterminator 

Rodents are more than just an unsightly nuisance; they pose significant risks to property and health. At Western Exterminator, we used service data from all our branches to identify the most rat-infested cities on the West Coast. Some cities with the most rats include Los Angeles, Santa Rosa, San Jose, Portland, Reno, and Seattle.

Not only are rodents carriers of various diseases, but their ability to gnaw through wires, pipes, and insulation can lead to costly damage. That’s why it's important for property owners to stay on top of pest activity and call for a rodent exterminator when needed. Keep reading to see if your city made the list for the West Coast.

Which city has the most rats and mice on the West Coast?

Cities like Los Angeles, San Francisco, San Jose, and Reno consistently top the list of cities with the most rats year after year. As these cities expand, they provide abundant food sources in the form of garbage and waste, as well as easily accessible shelter in buildings and alleys. Increasing temperatures in urban environments, like cities, can also extend the breeding season for rodents and alter their natural habitats, allowing them to explore new areas for food and nesting. 

Is your city on the list? Take a look at the cities with the worst rat problems on the West Coast*: 

1. Los Angeles, CA
2. Santa Rosa, CA
3. San Jose, CA
4. Long Beach, CA
5. Bakersfield, CA
6. Portland, OR 
7. San Rafael, CA
8. San Diego, CA
9. Beverly Hills, CA
10. Reno, NV
11. San Francisco, CA 
12. Sacramento, CA
13. Seattle, WA
14. Oakland, CA
15. Riverside, CA
16. South Lake Tahoe, CA
17. Napa, CA
18. Novato, CA
19. Salinas, CA
20. Vancouver, WA
21. Rancho Mirage, CA
22. Mammoth Lakes, CA
23. San Bernardino, CA
24. Fresno, CA
25. Pasadena, CA
26. Truckee, CA
27. Santa Barbara, CA
28. Carson, CA
29. Compton, CA
30. Glendale, CA
31. Palmdale, CA
32. Mill Valley, CA
33. Olympia, WA
34. Inglewood, CA
35. Lancaster, CA
36. Eugene, OR
37. Santa Cruz, CA
38. Redwood City, CA
39. Marysville, WA
40. Healdsburg, CA
41. Corona, CA
42. Sebastopol, CA
43. Palm Springs, CA
44. Stockton, CA
45. Oxnard, CA
46. Ridgecrest, CA
47. Torrance, CA
48. Fontana, CA
49. Tahoe City, CA
50. Huntington Beach, CA

Why do these West Coast cities have the most rodents?

The cities with the most rats share key factors that make them ideal environments for pest populations to thrive:

• Abundant food sources: High population density can generate large amounts of commercial garbage, food waste, and litter, which sustain large colonies.
• Dense urban infrastructure: Aging buildings, interconnected utility tunnels, and overgrown vegetation can provide countless hiding places and entry points.
• Favorable climate conditions: Mild coastal winters allow rats and mice to reproduce indoors nearly year-round without severe cold checks.

Are rodents in my home?

Rodents can be sneaky, but rats and mice often leave behind traces of their activity. It’s important to act quickly if you think rodents have invaded your property. Here are some signs of rats to look for: 

• Droppings: One of the most noticeable signs of a rodent infestation is their droppings. Rat droppings are about the size of a raisin, while mouse droppings are smaller and more pellet-like. You might find these droppings near food sources, along walls, or in hidden corners. 
• Gnaw marks: Rodents constantly need to gnaw to keep their teeth from growing too long. Look for gnaw marks on furniture, walls, wires, or food packaging. Due to their size, rats tend to leave larger marks than mice. 
• Nesting materials: If you notice shredded paper, fabric, or other materials in hidden areas, it could indicate that mice or rats are nesting nearby. They often use these materials to create warm, cozy nests. 
• Tracks: Small footprints might be found in dusty areas or attics. If you suspect rodent activity, sprinkle a little flour on the floor and check for footprints the next day. 
• Strange sounds: Rodents are often active at night, so listen for any scratching, scurrying, or squeaking sounds coming from inside walls, ceilings, or attics, especially during dusk or nighttime. 
• Foul odors: A strong, musky smell can indicate a rodent problem. This scent comes from their nests, droppings, and urine.

Preventing rodents in your home

Taking proactive steps is essential to keep pests out. Practice these essential rodent prevention tips to help protect your property:

1. Seal entry points: Patch cracks, holes, and gaps around foundations, vents, and utility pipes using steel wool and caulk.
2. Secure food supplies: Keep all food in airtight glass or thick plastic containers.
3. Manage trash: Store outdoor waste in sturdy trash cans equipped with tight-fitting lids.
4. Eliminate standing water: Fix leaking outdoor spouts and pipes, and clear clogged gutters to deprive rodents of water sources.
5. Trim vegetation: Keep tree branches and dense shrubs cut back at least three feet from your roofline and exterior walls.

Protect your home from rodents with Western Exterminator

If you live in one of the most rat-infested cities, it’s important to stay vigilant. At Western Exterminator, our technicians are trained to find where rodents hide and get rid of them. With a custom mouse control or rodent control plan in place, you can help protect your home no matter what city you’re in. 

*The cities listed are based on Nielsen’s Designated Market Areas (DMAs). A DMA may include multiple nearby cities and surrounding suburbs that function as one larger media market. For this reason, some entries may list more than one city together.