Metro area air quality · 2025
Salt Lake City, UT
Median AQI 57 (Moderate). 32.9% of monitored days rated Good across this metro's EPA monitoring network.
- 57
- Median AQI
- 32.9%
- Good-air days
- 1
- Unhealthy days
- 4%
- Cleaner than US metros
Salt Lake City, UT posted a 2025 median AQI of 57 (Moderate) with 32.9% Good days
According to the U.S. EPA Air Quality System, the Salt Lake City, UT CBSA recorded a median AQI of 57 across 365 monitored days in 2025, with 32.9% rated Good and 1 unhealthy or worse. This is an annual metro comparison, not a live advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US metros
- The Salt Lake City, UT CBSA's 32.9% Good-day share places it cleaner than 4% of US metros in 2025.
- Closest median-AQI peer
- Brownsville-Harlingen, TX (29.9% Good, median AQI 57) is the closest nationwide median-AQI peer to Salt Lake City, UT.
- 2020–2025 Good-day shift
- Salt Lake City, UT's Good-day share moved -5.0 points from 2020 to 2025 (median AQI +2).
- Median AQI
- Median AQI: 57
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Salt Lake City, UT lands in the lower Good-day tercile (32.9% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs moderate, among the more polluted US metros, with a median AQI of 57 and 32.9% of 365 monitored days in the Good band.
- 57
- median AQI · Moderate
- 32.9%
- days rated Good
- 4%
- cleaner than US metros
- 175
- worst single reading
1 day reached Unhealthy or worse across the metro's monitors in 2025.
Annual release change
What changed in the 2025 EPA annual release
- Salt Lake City, UT metro's Good-day share fell from 44.2% to 34.4% between the 2024 and 2025 EPA annual releases, a change of -9.8 percentage points.
- Salt Lake City, UT metro's peak single-day AQI fell from 230 to 175 between the 2024 and 2025 EPA annual releases, a change of -55 points.
- Salt Lake City, UT metro's Unhealthy-category days fell from 4 to 1 between the 2024 and 2025 EPA annual releases, a change of -3 days.
Salt Lake City, UT lands in the lower Good-day tercile (32.9% Good), a thinner clean-air share than most CBSA peers here. Signature read: 32.9% Good-day share (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 57 over 365 measured days in 2025 (Moderate / Poor). The monitored-day split lands at 120 Good (33%), 228 Moderate (62%), and 16 Unhealthy-for-Sensitive-Groups (4%). The 90th-percentile AQI finished at 90; the highest single-day reading hit 175 (Unhealthy).
Across 2020–2025, Good-day share shifted -5.0 points and median AQI moved +2 (worsening). The annual record contains 1 day at Unhealthy or worse. Metros with comparable AQI profiles include Brownsville-Harlingen, TX (29.9% good, AQI 57); Hanford-Corcoran, CA (34.5% good, AQI 57); Chicago-Naperville-Elgin, IL-IN-WI (29.9% good, AQI 56).
Air Quality Summary
Median AQI
57
Moderate
Good Days
32.9%
120 of 365 days
Max AQI
175
Unhealthy
Health Grade
Poor
90th pct: 90
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
120
33%
Moderate
228
62%
USG
16
4%
Unhealthy
1
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Salt Lake City, UT metro area's air quality is rated Poor based on 32.9% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality is acceptable most days, but 16 days reached "Unhealthy for Sensitive Groups" and peak AQI reached 175. Sensitive groups should monitor real-time conditions at AirNow.gov.
How does the Salt Lake City, UT metro compare?
How Salt Lake City, UT compares
5-Year Air Quality Trend
Air quality is worsening in the Salt Lake City, UT metro. Highest Good-day share: 2024 (44.2%, 144 of 326 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 135 | 207 | 1 | 55 | 214 |
| 2021 | 120 | 196 | 9 | 59 | 177 |
| 2022 | 99 | 238 | 0 | 61 | 147 |
| 2023 | 148 | 201 | 1 | 54 | 154 |
| 2024 | 144 | 178 | 4 | 56 | 230 |
| 2025 | 120 | 228 | 1 | 57 | 175 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Salt Lake City, UT (57).
Brownsville-Harlingen, TX
Median AQI 57 · 29.9% Good-day share
Hanford-Corcoran, CA
Median AQI 57 · 34.5% Good-day share
Chicago-Naperville-Elgin, IL-IN-WI
Median AQI 56 · 29.9% Good-day share
Cincinnati, OH-KY-IN
Median AQI 56 · 26.0% Good-day share
Denver-Aurora-Lakewood, CO
Median AQI 58 · 28.8% Good-day share
St. Louis, MO-IL
Median AQI 56 · 31.2% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Salt Lake City, UT's 1 (independent of median AQI).
Ann Arbor, MI
1 unhealthy-or-worse days · median AQI 41
Bangor, ME
1 unhealthy-or-worse days · median AQI 33
Baraboo, WI
1 unhealthy-or-worse days · median AQI 35
Bartlesville, OK
1 unhealthy-or-worse days · median AQI 44
Beaumont-Port Arthur, TX
1 unhealthy-or-worse days · median AQI 52
Beaver Dam, WI
1 unhealthy-or-worse days · median AQI 40
Frequently Asked Questions
How many unhealthy air days does Salt Lake City, UT have? ▼
What is the air quality in the Salt Lake City, UT metro area? ▼
Is air quality in Salt Lake City, UT getting better or worse? ▼
What does AQI 57 mean for health? ▼
How does Salt Lake City, UT compare to other metro areas? ▼
What is the 90th percentile AQI for Salt Lake City, UT? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Salt Lake City, UT, 2025. See our methodology for how AQI, median, and coverage figures are computed.
Read our methodology , how this data is sourced, computed, and verified.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Salt Lake City, UT · 2020–2025