Metro area air quality · 2025

Santa Maria-Santa Barbara, CA

Median AQI 52 (Moderate). 44.9% of monitored days rated Good across this metro's EPA monitoring network.

52
Median AQI
44.9%
Good-air days
0
Unhealthy days
10%
Cleaner than US metros

Santa Maria-Santa Barbara, CA posted a 2025 median AQI of 52 (Moderate) with 44.9% Good days

According to the U.S. EPA Air Quality System, the Santa Maria-Santa Barbara, CA CBSA recorded a median AQI of 52 across 365 monitored days in 2025, with 44.9% rated Good and 0 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 Santa Maria-Santa Barbara, CA CBSA's 44.9% Good-day share places it cleaner than 10% of US metros in 2025.
Closest median-AQI peer
Augusta-Richmond County, GA-SC (46.0% Good, median AQI 52) is the closest nationwide median-AQI peer to Santa Maria-Santa Barbara, CA.
2020–2025 Good-day shift
Santa Maria-Santa Barbara, CA's Good-day share moved -10.8 points from 2020 to 2025 (median AQI +4).
Median AQI
Median AQI: 52

Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →

The verdict

Santa Maria-Santa Barbara, CA lands in the lower Good-day tercile (44.9% 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 52 and 44.9% of 365 monitored days in the Good band.

52
median AQI · Moderate
44.9%
days rated Good
10%
cleaner than US metros
87
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Santa Maria-Santa Barbara, CA metro's Good-day share fell from 53.0% to 44.9% between the 2024 and 2025 EPA annual releases, a change of -8.1 percentage points.
  • Santa Maria-Santa Barbara, CA metro's peak single-day AQI fell from 146 to 87 between the 2024 and 2025 EPA annual releases, a change of -59 points.
  • Santa Maria-Santa Barbara, CA metro's median AQI rose from 49 to 52 between the 2024 and 2025 EPA annual releases, a change of +3 points.

Compared against 364 monitored days in 2024 and 365 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Santa Maria-Santa Barbara, CA lands in the lower Good-day tercile (44.9% Good), a thinner clean-air share than most CBSA peers here. Signature read: 44.9% 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 52 over 365 measured days in 2025 (Moderate / Poor). The monitored-day split lands at 164 Good (45%), 201 Moderate (55%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 61; the highest single-day reading hit 87 (Moderate).

Across 2020–2025, Good-day share shifted -10.8 points and median AQI moved +4 (worsening). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Augusta-Richmond County, GA-SC (46.0% good, AQI 52); Beaumont-Port Arthur, TX (41.4% good, AQI 52); Birmingham-Hoover, AL (43.0% good, AQI 52).

Health effects of air pollution →

Air Quality Summary

Median AQI

52

Moderate

Good Days

44.9%

164 of 365 days

Max AQI

87

Moderate

Health Grade

Poor

90th pct: 61

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

164

45%

Moderate

201

55%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Poor

The Santa Maria-Santa Barbara, CA metro area's air quality is rated Poor based on 44.9% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Santa Maria-Santa Barbara, CA metro compare?

How Santa Maria-Santa Barbara, CA compares

Good-day share worse than typical
Santa Maria-Santa Barbara, CA 44.9%
Augusta-Richmond County, GA-SC 46.0%
Typical US metro 70.6%
Median AQI worse than typical
Santa Maria-Santa Barbara, CA 52
Augusta-Richmond County, GA-SC 52
Typical US metro 41
Unhealthy days / yr better than typical
Santa Maria-Santa Barbara, CA 0
Augusta-Richmond County, GA-SC 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is worsening in the Santa Maria-Santa Barbara, CA metro. Highest Good-day share: 2021 (65.9%, 240 of 364 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 199 154 4 48
2021 240 124 0 44
2022 198 167 0 48
2023 232 133 0 45
2024 193 171 0 49
2025 164 201 0 52

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Santa Maria-Santa Barbara, CA (52).

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Santa Maria-Santa Barbara, CA's 0 (independent of median AQI).

Frequently Asked Questions

How many unhealthy air days does Santa Maria-Santa Barbara, CA have?
In 2025, the Santa Maria-Santa Barbara, CA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 87.
What is the air quality in the Santa Maria-Santa Barbara, CA metro area?
The Santa Maria-Santa Barbara, CA metro area has a median Air Quality Index (AQI) of 52, rated "Moderate." 44.9% of monitored days (164 out of 365) had good air quality in 2025.
Is air quality in Santa Maria-Santa Barbara, CA getting better or worse?
Air quality in the Santa Maria-Santa Barbara, CA metro is worsening across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2021 at 65.9% (240 of 364 days). Lowest qualifying Good-day share: 2025 at 44.9% (164 of 365 days).
What does AQI 52 mean for health?
An AQI of 52 is "Moderate", air quality is acceptable, but some pollutants may pose a moderate health concern for a small number of sensitive individuals.
How does Santa Maria-Santa Barbara, CA compare to other metro areas?
The Santa Maria-Santa Barbara, CA metro has 44.9% good air days. Similar metros: Augusta-Richmond County, GA-SC (46.0% good), Beaumont-Port Arthur, TX (41.4% good), Birmingham-Hoover, AL (43.0% good).
What is the 90th percentile AQI for Santa Maria-Santa Barbara, CA?
The 90th percentile AQI for the Santa Maria-Santa Barbara, CA metro area is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 87 (Moderate).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Santa Maria-Santa Barbara, CA, 2025. See our methodology for how AQI, median, and coverage figures are computed.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Santa Maria-Santa Barbara, CA · 2020–2025