Route on-time record
GSP to DEN: most on-time flights and the best time to fly
Greenville/Greer/Spartanburg (Greenville-Spartanburg International Airport) to Denver (Denver International Airport). 383 nonstop flights in Jun 2025 to May 2026, 79% arrived within 15 minutes and 1.0% were cancelled. The most reliable flight number was United 1417 at 4:15 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
GSP → DEN
Greenville/Greer/Spartanburg to Denver: 383 nonstop flights a year
On time (12 months)
79%
Cancelled
1.0%
avg delay 15 min
Best time to leave
No clear winner
Most reliable airline
SkyWest
81% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · United 1417
4:15 PM → 5:55 PM3h 40m nonstop
Local times, typical schedule. Last flown 2026-05-31.
82%
chance on time
- On time (history)
- 91%
- Cancelled
- 0.0%
- Avg arrival delay
- 3 min
- Arrived on time 91% of the time (11 flights, Jun 2025 to May 2026).
- Lands inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (11 flights), so its score leans on the airline's record at this hour.
Limited track record · 11 flights
Find United 1417 fares Opens this date on Aviasales#2 · SkyWest 5809 · sold as United Express, Delta Connection, American Eagle or Alaska
4:10 PM → 6:00 PM3h 50m nonstop
Local times, typical schedule. Last flown 2026-04-29. Same departure also flew as SkyWest 5892; its record covers all of them.
81%
chance on time
- On time (history)
- 85%
- Cancelled
- 2.8%
- Avg arrival delay
- 8 min
- Arrived on time 85% of the time (136 flights, Jun 2025 to May 2026).
- Lands inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 136 flights
Find 4:10 PM flight fares Opens this date on Aviasales#3 · United 1544
4:35 PM → 6:14 PM3h 39m nonstop
Local times, typical schedule. Last flown 2026-05-20.
79%
chance on time
- On time (history)
- 76%
- Cancelled
- 0.0%
- Avg arrival delay
- 14 min
- Arrived on time 76% of the time (21 flights, Jun 2025 to May 2026).
- Lands inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (21 flights), so its score leans on the airline's record at this hour.
Limited track record · 21 flights
Find United 1544 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- SkyWest Airlines (sold as United Express, Delta Connection, American Eagle or Alaska)81%
142 flights · 85% on time as flown · 1.9% cancel
- United Airlines79%
223 flights · 79% on time as flown · 0.4% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- 3 to 6 PM79%
373 flights · avg delay 15 min
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Air traffic control and airport volume69%
- Late-arriving aircraft15%
- Airline (crew, maintenance, boarding)13%
- Severe weather3%
Share of delay minutes by the cause airlines report to the US DOT.
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure
GSP to DEN questions
- Which airline is most on time from GSP to DEN?
- SkyWest, with a season-adjusted 81% chance of operating and arriving on time over 142 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on GSP to DEN?
- July (64% on time); the best was March (93%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from GSP
- DEN to GSP (return)
- GSP to ATL 89%
- GSP to ORD 75%
- GSP to CLT 83%
- GSP to DFW 74%
- GSP to DCA 68%
- GSP to LGA 76%
- GSP to EWR 86%
- GSP to MIA 80%
- GSP to BWI 89%
- GSP to DTW 85%
- GSP to BNA 89%
- GSP to PHL 88%
Live status: FAA delays and ground stops