Metro area air quality · 2025

Greenville, NC

Median AQI 37 (Good). 88.0% of monitored days rated Good across this metro's EPA monitoring network.

37
Median AQI
88.0%
Good-air days
0
Unhealthy days
83%
Cleaner than US metros

Greenville, NC posted a 2025 median AQI of 37 (Good) with 88.0% Good days

According to the U.S. EPA Air Quality System, the Greenville, NC CBSA recorded a median AQI of 37 across 365 monitored days in 2025, with 88.0% 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 Greenville, NC CBSA's 88.0% Good-day share places it cleaner than 83% of US metros in 2025.
Closest median-AQI peer
Alexandria, LA (73.7% Good, median AQI 37) is the closest nationwide median-AQI peer to Greenville, NC.
2020–2025 Good-day shift
Greenville, NC's Good-day share moved +1.2 points from 2020 to 2025 (median AQI +1).
Median AQI
Median AQI: 37

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

The verdict

Greenville, NC sits in the upper Good-day tercile among EPA CBSA metros on this site (88.0% of 365 monitored days). On the EPA scale the metro runs good, cleaner than most US metros, with a median AQI of 37 and 88.0% of 365 monitored days in the Good band.

37
median AQI · Good
88.0%
days rated Good
83%
cleaner than US metros
71
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
  • Greenville, NC metro's Good-day share rose from 85.8% to 87.9% between the 2024 and 2025 EPA annual releases, a change of +2.1 percentage points.

Compared against 352 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

Greenville, NC sits in the upper Good-day tercile among EPA CBSA metros on this site (88.0% of 365 monitored days). Signature read: 88.0% Good-day share (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 37 over 365 measured days in 2025 (Good / Good). The monitored-day split lands at 321 Good (88%), 44 Moderate (12%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 52; the highest single-day reading hit 71 (Moderate).

Across 2020–2025, Good-day share shifted +1.2 points and median AQI moved +1 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Alexandria, LA (73.7% good, AQI 37); Athens, TN (78.2% good, AQI 37); Bennington, VT (83.6% good, AQI 37).

Best and worst city air quality →

Air Quality Summary

Median AQI

37

Good

Good Days

88.0%

321 of 365 days

Max AQI

71

Moderate

Health Grade

Good

90th pct: 52

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

321

88%

Moderate

44

12%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Greenville, NC metro area's air quality is rated Good based on 88.0% 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 Greenville, NC metro compare?

How Greenville, NC compares

Good-day share better than typical
Greenville, NC 88.0%
Alexandria, LA 73.7%
Typical US metro 70.6%
Median AQI better than typical
Greenville, NC 37
Alexandria, LA 37
Typical US metro 41
Unhealthy days / yr better than typical
Greenville, NC 0
Alexandria, LA 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Greenville, NC metro. Highest Good-day share: 2025 (87.9%, 321 of 365 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 313 48 0 36
2021 288 72 0 39
2022 305 60 0 37
2023 256 107 0 42
2024 302 50 0 37
2025 321 44 0 37

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Greenville, NC (37).

Alexandria, LA

Median AQI 37 · 73.7% Good-day share

37

Athens, TN

Median AQI 37 · 78.2% Good-day share

37

Bennington, VT

Median AQI 37 · 83.6% Good-day share

37

Blacksburg-Christiansburg-Radford, VA

Median AQI 37 · 94.4% Good-day share

37

Cadillac, MI

Median AQI 37 · 86.0% Good-day share

37

Chambersburg-Waynesboro, PA

Median AQI 37 · 91.5% Good-day share

37

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Greenville, NC'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 Greenville, NC have? ▼
In 2025, the Greenville, NC metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 71.
What is the air quality in the Greenville, NC metro area? ▼
The Greenville, NC metro area has a median Air Quality Index (AQI) of 37, rated "Good." 88.0% of monitored days (321 out of 365) had good air quality in 2025.
Is air quality in Greenville, NC getting better or worse? ▼
Air quality in the Greenville, NC metro is stable 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 87.9% (321 of 365 days). Lowest qualifying Good-day share: 2023 at 70.5% (256 of 363 days).
What does AQI 37 mean for health? ▼
An AQI of 37 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 Greenville, NC compare to other metro areas? ▼
The Greenville, NC metro has 88.0% good air days. Similar metros: Alexandria, LA (73.7% good), Athens, TN (78.2% good), Bennington, VT (83.6% good).
What is the 90th percentile AQI for Greenville, NC? ▼
The 90th percentile AQI for the Greenville, NC metro area is 52, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 71 (Moderate).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Greenville, NC, 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, Greenville, NC · 2020–2025