Los Angeles Tops National ‘Rattiest City’ List

For the first time in more than a decade, Los Angeles has claimed the top spot on Orkin's annual Rattiest Cities List, ending Chicago's reign that began when the rankings debuted.

The pest control company announced that the City of Angels had moved up one spot to No. 1, displacing Chicago to second place. New York ranked third, followed by San Francisco at fourth.

Orkin determined the rankings by tracking new rodent services in owner-occupied residences from Aug. 20, 2024, to Aug. 21, 2025. The company attributed Los Angeles' rise to year-round warm weather, a booming culinary scene and dense neighborhoods that provide ample food and shelter for rodents.

California dominated the list with four cities in the top 50: Los Angeles, San Francisco, Sacramento at No. 19 and San Diego at No. 24.

The shift in rankings reflects changing rodent activity patterns influenced by weather, urban infrastructure and human behavior, according to Orkin officials. Moderate climates improve rodent survival rates while urban sprawl creates new pathways for infestations.

Rodents pose serious risks beyond being a nuisance, experts warn. They can cause significant structural damage by gnawing through walls, wiring and pipes — a rat's teeth rank 5.5 on the Mohs hardness scale, strong enough to chew through steel garbage cans. The pests are known carriers of illnesses including leptospirosis, salmonellosis, plague and typhus.

"Rats and mice are more than a nuisance — they're opportunists," said Ian Williams, an Orkin entomologist. "If there's food, warmth and a way in, they'll find it. And once inside, their constant chewing and rapid reproduction can quickly turn a small issue into a large, expensive one."

Santa Monica has experienced its share of rodent problems in recent years, with high-profile incidents affecting both public spaces and private businesses.

In 2020, longtime Third Street Promenade property owner John Alle complained that rats and mice were nesting inside the pedestrian mall's signature dinosaur-shaped topiary planters. He observed "swarms of rodents" routinely scurrying in and out of the ivy-covered metal sculptures after dark, particularly concerning given the proximity to outdoor dining areas during the COVID-19 pandemic.

The city's rodent issues have extended to restaurants and food establishments. Several local restaurants have been cited by the health department in the past few years over vermin problems. While most were able to clean up and reopen, at least one cited rats as part of the reason for their closure.

Tacos Punta Cabras opened at Broadway and 10th Street in 2018 but shut down barely a year later due to severe roof leaks and a rodent infestation so extensive the owners could hear rats scrambling in the walls. The restaurant's proprietors sued their landlord, and a jury awarded them approximately $3 million in 2023, finding the landlords' failure to address the infestation amounted to wrongful eviction.

The health consequences of rodent infestations became particularly alarming in summer 2025 when public health officials investigated a cluster of five flea-borne typhus cases in Santa Monica. All five patients required hospitalization. Disease investigators conducted environmental assessments near 25th Street and Kansas Avenue, where fleas collected from animals tested positive for typhus bacteria. The outbreak highlighted how rats serve as vectors for disease, carrying infected fleas that can transmit illness to humans.

To combat rodent problems, Orkin recommends following "GNAW" prevention tips: Guard entry points by sealing cracks and gaps; Never leave food unattended outside; Avoid clutter that creates nesting spots; and Watch for signs like droppings, gnaw marks or burrows. Rats need only an opening the size of a quarter to access a building, while mice require even less space.