Greer, SC

What the Data Says About GSP

Greer, SC in Greer, South Carolina handled 155,526 flights in the Bureau of Transportation Statistics dataset between 2020 and 2025, posting a 83.5% on-time departure rate. Of those flights, 25,645 experienced delays, 1,749 were cancelled, and 164 were diverted. The cancellation rate works out to 1.12%, the diversion rate to 0.11%, and the average delay when departures run late is 77.4 minutes. These figures are the baseline for comparing GSP against other airports in the same state and nationally.

Breaking down what drives delays at GSP, Late Aircraft leads the pack. Late Aircraft accounts for 40.8% of total delay minutes, followed by Carrier at 34.1% and NAS (National Aviation System) at 19.6%. Weather contributes 5.3% of delay minutes at this airport, while security holds the smallest share at 0.1%. Travelers often overestimate the weather share; the BTS categorization shows late-arriving aircraft and carrier operations as the larger contributors.

Seasonally, September runs the cleanest at GSP with a 94.8% on-time rate, while July is the roughest at 89.4% — a 5-point swing between best and worst month. Volume peaks in October, when average flights hit 2,282. The busiest route from GSP is to ATL (Atlanta), with 18,285 flights at a 91.8% on-time rate. Combine these numbers — 83.5% on-time, 77.4-minute average delay, 1.12% cancellation rate — and you have a concrete picture of departure reliability at Greer, SC.