Metro area air quality · 2025

South Bend-Mishawaka, IN-MI

Median AQI 43 (Good). 66.0% of monitored days rated Good across this metro's EPA monitoring network.

43
Median AQI
66.0%
Good-air days
0
Unhealthy days
36%
Cleaner than US metros

South Bend-Mishawaka, IN-MI posted a 2025 median AQI of 43 (Good) with 66.0% Good days

According to the U.S. EPA Air Quality System, the South Bend-Mishawaka, IN-MI CBSA recorded a median AQI of 43 across 365 monitored days in 2025, with 66.0% 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 South Bend-Mishawaka, IN-MI CBSA's 66.0% Good-day share places it cleaner than 36% of US metros in 2025.
Closest median-AQI peer
Ashtabula, OH (81.2% Good, median AQI 43) is the closest nationwide median-AQI peer to South Bend-Mishawaka, IN-MI.
2020–2025 Good-day shift
South Bend-Mishawaka, IN-MI's Good-day share moved +11.8 points from 2020 to 2025 (median AQI -5).
Median AQI
Median AQI: 43

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

The verdict

South Bend-Mishawaka, IN-MI's Good-day share (66.0%) sits in the middle CBSA tercile on this extract. On the EPA scale the metro runs good, more polluted than the median US metro, with a median AQI of 43 and 66.0% of 365 monitored days in the Good band.

43
median AQI · Good
66.0%
days rated Good
36%
cleaner than US metros
127
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
  • South Bend-Mishawaka, IN-MI metro's Good-day share rose from 65.1% to 67.3% between the 2024 and 2025 EPA annual releases, a change of +2.2 percentage points.

Compared against 364 monitored days in 2024 and 358 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

South Bend-Mishawaka, IN-MI's Good-day share (66.0%) sits in the middle CBSA tercile on this extract. Signature read: 66.0% Good-day share (mid tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 43 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 241 Good (66%), 117 Moderate (32%), and 7 Unhealthy-for-Sensitive-Groups (2%). The 90th-percentile AQI finished at 71; the highest single-day reading hit 127 (USG).

Across 2020–2025, Good-day share shifted +11.8 points and median AQI moved -5 (improving). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Ashtabula, OH (81.2% good, AQI 43); Bloomington, IN (67.7% good, AQI 43); Champaign-Urbana, IL (65.8% good, AQI 43).

Understanding AQI →

Air Quality Summary

Median AQI

43

Good

Good Days

66.0%

241 of 365 days

Max AQI

127

USG

Health Grade

Moderate

90th pct: 71

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

241

66%

Moderate

117

32%

USG

7

2%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The South Bend-Mishawaka, IN-MI metro area's air quality is rated Moderate based on 66.0% 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 South Bend-Mishawaka, IN-MI metro compare?

How South Bend-Mishawaka, IN-MI compares

Good-day share worse than typical
South Bend-Mishawaka, IN-MI 66.0%
Ashtabula, OH 81.2%
Typical US metro 70.6%
Median AQI worse than typical
South Bend-Mishawaka, IN-MI 43
Ashtabula, OH 43
Typical US metro 41
Unhealthy days / yr better than typical
South Bend-Mishawaka, IN-MI 0
Ashtabula, OH 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is improving in the South Bend-Mishawaka, IN-MI metro. Highest Good-day share: 2025 (67.3%, 241 of 358 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 200 159 1 48
2021 169 195 0 52
2022 167 192 0 52
2023 172 180 2 52
2024 237 127 0 45
2025 241 117 0 43

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near South Bend-Mishawaka, IN-MI (43).

Ashtabula, OH

Median AQI 43 · 81.2% Good-day share

43

Bloomington, IN

Median AQI 43 · 67.7% Good-day share

43

Champaign-Urbana, IL

Median AQI 43 · 65.8% Good-day share

43

Cleveland, MS

Median AQI 43 · 71.9% Good-day share

43

Columbus, IN

Median AQI 43 · 72.6% Good-day share

43

Durham-Chapel Hill, NC

Median AQI 43 · 71.5% Good-day share

43

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to South Bend-Mishawaka, IN-MI's 0 (independent of median AQI).

Aberdeen, SD

0 unhealthy-or-worse days · median AQI 27

27

Aberdeen, WA

0 unhealthy-or-worse days · median AQI 22

22

Adrian, MI

0 unhealthy-or-worse days · median AQI 41

41

Akron, OH

0 unhealthy-or-worse days · median AQI 45

45

Albany, GA

0 unhealthy-or-worse days · median AQI 46

46

Albany, OR

0 unhealthy-or-worse days · median AQI 27

27

Frequently Asked Questions

How many unhealthy air days does South Bend-Mishawaka, IN-MI have? ▼
In 2025, the South Bend-Mishawaka, IN-MI metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 127.
What is the air quality in the South Bend-Mishawaka, IN-MI metro area? ▼
The South Bend-Mishawaka, IN-MI metro area has a median Air Quality Index (AQI) of 43, rated "Good." 66.0% of monitored days (241 out of 365) had good air quality in 2025.
Is air quality in South Bend-Mishawaka, IN-MI getting better or worse? ▼
Air quality in the South Bend-Mishawaka, IN-MI metro is improving across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2025 at 67.3% (241 of 358 days). Lowest qualifying Good-day share: 2021 at 46.4% (169 of 364 days).
What does AQI 43 mean for health? ▼
An AQI of 43 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How does South Bend-Mishawaka, IN-MI compare to other metro areas? ▼
The South Bend-Mishawaka, IN-MI metro has 66.0% good air days. Similar metros: Ashtabula, OH (81.2% good), Bloomington, IN (67.7% good), Champaign-Urbana, IL (65.8% good).
What is the 90th percentile AQI for South Bend-Mishawaka, IN-MI? ▼
The 90th percentile AQI for the South Bend-Mishawaka, IN-MI metro area is 71, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 127 (USG).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for South Bend-Mishawaka, IN-MI, 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, South Bend-Mishawaka, IN-MI · 2020–2025