Best time to fly out of Greenville-Spartanburg (GSP)
The early-flight folk wisdom holds up at Greenville-Spartanburg: departures in the Before 6am band left on time 93.1% of the time, against 66.2% in the 8–10pm band. These are historical odds, not forecasts. The records say what happened on this schedule over three years; they know nothing about tomorrow’s thunderstorm.
Data through June 2026 · Bureau of Transportation Statistics
On-time rate by hour and day
On this page, “on time” means a departure that pushed back less than 15 minutes behind its scheduled time — the Bureau of Transportation Statistics definition, and the one airlines are held to.
| Departure time | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|---|
| Before 6am | 92 | 95 | 95 | 92 | 94 | 92 | 92 |
| 6–8am | 89 | 92 | 91 | 92 | 91 | 90 | 91 |
| 8–10am | 87 | 90 | 89 | 90 | 91 | 89 | 90 |
| 10am–12pm | 84 | 86 | 87 | 86 | 81 | 86 | 86 |
| 12–2pm | 80 | 83 | 87 | 87 | 82 | 84 | 83 |
| 2–4pm | 76 | 88 | 82 | 82 | 80 | 81 | 73 |
| 4–6pm | 75 | 79 | 79 | 75 | 72 | 77 | 73 |
| 6–8pm | 71 | 75 | 77 | 69 | 74 | 68 | 69 |
| 8–10pm | 61 | 76 | 69 | 67 | 67 | – | 64 |
| 10pm–12am | – | – | – | – | – | – | – |
The steadiest stretch at GSP was Before 6am — 93.1% of departures left on time across 2,588 flights. The weakest was 8–10pm at 66.2%. 6–8am departures from GSP left on time 90.9% of the time across 11,305 flights; 6–8pm departures, 71.9% across 5,446. That is a gap of 19 points, and it is the whole case for the early flight.
The year at GSP
July was the hard month at GSP: 75.5% of departures left on time, across 3,981 flights. November was the easy one at 88.2%. Each month pools three years of that month, so a single bad week does not decide it.
| Month | Share departures that left on time | Flights |
|---|---|---|
| January | 83.1% | 3,414 |
| February | 85.9% | 3,278 |
| March | 83.2% | 3,686 |
| April | 86.5% | 3,590 |
| May | 79.3% | 4,016 |
| June | 77.7% | 3,890 |
| July | 75.5% | 3,981 |
| August | 84.3% | 3,863 |
| September | 87.8% | 3,603 |
| October | 87.9% | 3,892 |
| November | 88.2% | 3,687 |
| December | 81.6% | 3,673 |
Airlines at GSP
Every airline with at least 100 departures from GSP, busiest first. These are that airline’s departures from this airport only — its record across the country sits on its own page.
| Airline | Left on time | Typical delay | Cancelled | Departures |
|---|---|---|---|---|
| PSA Airlines | 82.3% | 91 min | 2.1% | 10,187 |
| Delta Air Lines | 89% | 78 min | 1.2% | 8,462 |
| Republic Airways | 86.8% | 85 min | 3.7% | 5,998 |
| Envoy Air | 81.2% | 68 min | 1.4% | 4,931 |
| Southwest Airlines | 81.8% | 52 min | 0.7% | 4,408 |
| American Airlines | 75% | 95 min | 2.4% | 3,564 |
| SkyWest Airlines | 83.8% | 91 min | 2% | 2,656 |
| Endeavor Air | 87.1% | 89 min | 2.6% | 1,938 |
| United Airlines | 87.1% | 106 min | 0.7% | 1,290 |
| Allegiant Air | 61% | 88 min | 1.5% | 1,139 |
What delays out of GSP were put down to
Airlines file a reason with every arrival running 15 minutes late or more. Across 7,649 flights that departed GSP and ran 15 minutes late or more, the delay minutes break down with 43.3% put down to late-arriving aircraft and 31.3% to airline operations.
- Late-arriving aircraft 43.3%
- Airline operations 31.3%
- Air traffic & airport volume 19.2%
- Severe weather 6.1%
- Security 0.1%
Late-arriving aircraft is the knock-on category: the plane came in late, so it went out late again. It is why a 7am problem in Newark is still a problem in Denver at dinnertime, and why it is usually the biggest slice on the bar.
If you are connecting through GSP
Of 44,578 scheduled arrivals into GSP, 76.4% reached the gate less than 15 minutes behind schedule. Of the 9,609 arrivals that ran late, 52.8% were no more than 45 minutes behind — which is the difference between a tight connection and a new boarding pass.
Work out a specific layover — pick the airport and the minutes you have, and the tool reads the same arrival records back as a share.
Busiest routes out of GSP
Ranked by flights, with the share that arrived on time at the far end. Where a route carries enough flights for a page of its own the chip goes there; otherwise it goes to the destination airport.
- ATL 90.1% on time · 8,881 flights
- CLT 79% on time · 7,481 flights
- ORD 78.9% on time · 4,403 flights
- LGA 83.9% on time · 3,877 flights
- DFW 76% on time · 3,438 flights
- DCA 74.5% on time · 3,018 flights
- EWR 87.3% on time · 2,394 flights
- BWI 85.1% on time · 1,831 flights
- DTW 87.3% on time · 1,700 flights
- MIA 83.4% on time · 1,664 flights
GSP in one number
Greenville-Spartanburg (GSP)
Rank 83 of 363 US airports by departures. Steadiest stretch of the day: Before 6am. Hardest month: July.
Questions about GSP
- What is the best time of day to fly out of Greenville-Spartanburg?
- Before 6am. Departures in that band left on time 93.1% of the time across 2,588 flights, July 2023 through June 2026 — the best of the ten bands in the day. The 8–10pm band was the weakest at 66.2%.
- Is the early flight out of GSP really more reliable?
- 6–8am departures from GSP left on time 90.9% of the time across 11,305 flights; 6–8pm departures, 71.9% across 5,446. That is a gap of 19 points, and it is the whole case for the early flight.
- What is the worst month to fly out of GSP?
- July: 75.5% of the departures that flew left on time, with 3,981 scheduled. November was the other end of the year at 88.2%. Each figure pools three years of that calendar month.
- Which airline is most on time at GSP?
- Delta Air Lines — 89% of its 8,462 departures from GSP left on time. Allegiant Air sat at the other end at 61% over 1,139 flights. Only airlines with at least 100 departures here are ranked.
- How often are flights cancelled at GSP?
- 1.9% of scheduled departures were cancelled over July 2023 through June 2026. Cancellations are counted against everything scheduled, not against everything that flew — a rate that looks small still adds up to real people in a rebooking line.