San Juan named one of the cleanest cities for air quality in US
Puerto Rico’s capital was one of only two U.S. cities to earn top marks in all pollution categories in the 2025 “State of the Air” report.
The municipality of San Juan has once again earned national recognition for its clean air, ranking among the cleanest U.S. cities in the American Lung Association’s 2025 “State of the Air” report.
San Juan was one of only two U.S. cities to receive top marks across all three pollution categories in the report, which analyzed data from 2021 to 2023.
“This year, there are only two cities — Bangor, Maine and San Juan, Puerto Rico — that made the cleanest cities list for all three pollution measures,” the report stated.
The measures include the number of high ozone days, spikes in short-term particle pollution and levels of year-round particle pollution.
Six of Puerto Rico’s 78 counties were included in the analysis. Although the island has a limited air monitoring network, available data ranked San Juan among the most pollution-free metropolitan areas in the U.S.
Nationally, the report presented a stark contrast: “156 million people in the U.S. (46%) live in an area that received a failing grade for at least one measure of air pollution,” the report said. That figure includes 42.5 million residents living in areas that failed all three categories. Climate change-related wildfires and extreme heat were cited as major contributors to worsening air quality across many regions.
Puerto Rico, and San Juan in particular, showed no such declines.
“This reflects an overall worsening of air quality across the country. Last year, there were five cities on this list,” the report added, noting the reduced number of clean-air cities this year.
San Juan’s continued inclusion not only highlights its air quality but also underscores Puerto Rico’s broader public health performance in a year when much of the country saw environmental setbacks.
