Metro area air quality · 2025

Spartanburg, SC

Median AQI 48 (Good). 55.1% of monitored days rated Good across this metro's EPA monitoring network.

48
Median AQI
55.1%
Good-air days
0
Unhealthy days
17%
Cleaner than US metros

Spartanburg, SC posted a 2025 median AQI of 48 (Good) with 55.1% Good days

According to the U.S. EPA Air Quality System, the Spartanburg, SC CBSA recorded a median AQI of 48 across 365 monitored days in 2025, with 55.1% 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 Spartanburg, SC CBSA's 55.1% Good-day share places it cleaner than 17% of US metros in 2025.
Closest median-AQI peer
Baltimore-Columbia-Towson, MD (58.1% Good, median AQI 48) is the closest nationwide median-AQI peer to Spartanburg, SC.
2020–2025 Good-day shift
Spartanburg, SC's Good-day share moved -8.7 points from 2020 to 2025 (median AQI +3).
Median AQI
Median AQI: 48

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

The verdict

Spartanburg, SC lands in the lower Good-day tercile (55.1% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs good, among the more polluted US metros, with a median AQI of 48 and 55.1% of 365 monitored days in the Good band.

48
median AQI · Good
55.1%
days rated Good
17%
cleaner than US metros
93
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
  • Spartanburg, SC metro's Good-day share rose from 52.4% to 55.1% between the 2024 and 2025 EPA annual releases, a change of +2.7 percentage points.
  • Spartanburg, SC metro's peak single-day AQI fell from 112 to 93 between the 2024 and 2025 EPA annual releases, a change of -19 points.

Compared against 359 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

Spartanburg, SC lands in the lower Good-day tercile (55.1% Good), a thinner clean-air share than most CBSA peers here. Signature read: 55.1% 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 48 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 201 Good (55%), 164 Moderate (45%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 62; the highest single-day reading hit 93 (Moderate).

Across 2020–2025, Good-day share shifted -8.7 points and median AQI moved +3 (worsening). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Baltimore-Columbia-Towson, MD (58.1% good, AQI 48); Boulder, CO (58.4% good, AQI 48); Columbus, GA-AL (53.4% good, AQI 48).

Health effects of air pollution →

Air Quality Summary

Median AQI

48

Good

Good Days

55.1%

201 of 365 days

Max AQI

93

Moderate

Health Grade

Moderate

90th pct: 62

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

201

55%

Moderate

164

45%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Spartanburg, SC metro area's air quality is rated Moderate based on 55.1% 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 Spartanburg, SC metro compare?

How Spartanburg, SC compares

Good-day share worse than typical
Spartanburg, SC 55.1%
Baltimore-Columbia-Towson, MD 58.1%
Typical US metro 70.6%
Median AQI worse than typical
Spartanburg, SC 48
Baltimore-Columbia-Towson, MD 48
Typical US metro 41
Unhealthy days / yr better than typical
Spartanburg, SC 0
Baltimore-Columbia-Towson, MD 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is worsening in the Spartanburg, SC metro. Highest Good-day share: 2020 (63.7%, 232 of 364 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 232 132 0 45
2021 201 152 0 46
2022 206 157 0 47
2023 166 194 0 51
2024 188 171 0 49
2025 201 164 0 48

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Spartanburg, SC (48).

Baltimore-Columbia-Towson, MD

Median AQI 48 · 58.1% Good-day share

48

Boulder, CO

Median AQI 48 · 58.4% Good-day share

48

Columbus, GA-AL

Median AQI 48 · 53.4% Good-day share

48

Durango, CO

Median AQI 48 · 60.8% Good-day share

48

Greenville-Anderson-Mauldin, SC

Median AQI 48 · 55.3% Good-day share

48

Knoxville, TN

Median AQI 48 · 56.4% Good-day share

48

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Spartanburg, SC'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 Spartanburg, SC have? ▼
In 2025, the Spartanburg, SC metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 93.
What is the air quality in the Spartanburg, SC metro area? ▼
The Spartanburg, SC metro area has a median Air Quality Index (AQI) of 48, rated "Good." 55.1% of monitored days (201 out of 365) had good air quality in 2025.
Is air quality in Spartanburg, SC getting better or worse? ▼
Air quality in the Spartanburg, SC 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: 2020 at 63.7% (232 of 364 days). Lowest qualifying Good-day share: 2023 at 46.1% (166 of 360 days).
What does AQI 48 mean for health? ▼
An AQI of 48 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 Spartanburg, SC compare to other metro areas? ▼
The Spartanburg, SC metro has 55.1% good air days. Similar metros: Baltimore-Columbia-Towson, MD (58.1% good), Boulder, CO (58.4% good), Columbus, GA-AL (53.4% good).
What is the 90th percentile AQI for Spartanburg, SC? ▼
The 90th percentile AQI for the Spartanburg, SC metro area is 62, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 93 (Moderate).

Data Sources

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