California's Cleanest City Is This Pleasantly Named San Francisco Suburb, Per A 2025 Survey

California cities often get a bad rap for being dirty, and some critics blast San Francisco as a cesspool with few redeeming qualities. A 2025 survey from LawnStarter examined the cleanliness of more than 300 of the biggest cities across America to find out which ones are the dirtiest. Southern California enclaves make up the lion's share of Golden State entries on the dirty list, but municipalities in Northern California and the Bay Area are largely absent. Of the 10 cleanest cities on the list, California is only represented by one place: Pleasanton, a thriving suburb sandwiched between San Francisco and Fremont, packed with parks and family-friendly fun. 

To make its determinations, LawnStarter gathered data pertaining to quality of life in these places and broke them down into categories measuring pollution, inadequate living conditions, insufficient waste infrastructure, and overall resident dissatisfaction. For pollution, experts examined statistics like the median air quality index, water quality violations, and greenhouse gas emissions per capita. Lack of landfills and proper trash receptacles factored into the inadequate waste infrastructure metric, while inadequate living conditions were determined by things like the number of homes without proper kitchens and plumbing. 

As far as measuring residents' satisfaction — or lack thereof — with their surroundings, the study focused on the percentage of residents who were upset with the lack of public green space and local garbage disposal, as well as dissatisfaction with pollution in their cities and how many believe their cities are dirty or untidy. In the end, Pleasanton came in toward the bottom of the list — one of the few times you want to come closer to being last than first. 

The latest findings add to Pleasanton's accolades as an unmatched locale for quality of life in the Golden State. In fact, earlier in 2025 it was deemed the second-best city for quality of life in the country by the Social Progress Imperative (via the City of Pleasanton). Coincidentally, it was beaten for first by San Ramon, about 20 minutes north, and Fremont, about half an hour southwest of Pleasanton, rounded out the top 10. 

Even though just walking around Pleasanton is, well, pleasant, you could still escape the city-like atmosphere that might inherently feel dirty at times, even if Pleasanton itself is not. Luckily, the town is nestled between some underrated nature reserves and green spaces that offer unparalleled Northern California beauty. Augustin Bernal Park, for example, has stunning views of the surrounding Bay Area 'burbs, as do the sprawling Pleasanton Ridge Regional Park and Shadow Cliffs Regional Recreation Area. Breathe in some of that fresh Pleasanton air and you'll learn why it earned its place as one of the country's cleanest cities. If you want a fun day trip into a more remote landscape, Sugarloaf Ridge State Park offers gorgeous waterfalls and colorful scenery that is perfect to visit during winter, about a one-and-a-half-hour drive away.

Pleasanton ranked as one of the least dirty cities in the country, thanks to factors like superb air and water quality and local satisfaction with the surrounding environment and city waste management services. The town might be an attractive place to live for those reasons alone, but there's much more than what meets the eye in this idyllic San Francisco suburb, especially when it comes to cultivating community.

The city often comes together for community happenings like the Alameda County Fair and cultural outings like Asian night markets, Diwali celebrations, and a nearly Scottish Games event. The summertime Thrift Fest and Alameda Vintage Fashion Faire are great places to find secondhand clothes (and avoid letting them get sent to landfills, thereby further preserving Pleasanton's clean charm). While two of America's cleanest cities are located in the Pacific Northwest, you'll be able to escape some of California's smog while engaging in fun activities in Pleasanton.