Best time to fly out of Great Falls (GTF)
The early-flight folk wisdom holds up at Great Falls: departures in the Before 6am band left on time 96.2% of the time, against 80.5% in the 2–4pm 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 | 97 | 96 | 98 | 97 | 97 | 94 | 95 |
| 6–8am | 94 | 95 | 95 | 92 | 93 | 95 | 93 |
| 8–10am | – | – | – | – | – | – | – |
| 10am–12pm | – | – | – | – | – | – | – |
| 12–2pm | 92 | 97 | 95 | 88 | 92 | 91 | 93 |
| 2–4pm | 77 | 79 | 82 | 82 | 81 | 79 | 83 |
| 4–6pm | – | – | – | – | – | – | – |
| 6–8pm | 85 | 91 | 92 | 88 | 87 | – | 83 |
| 8–10pm | – | – | – | – | – | – | – |
| 10pm–12am | – | – | – | – | – | – | – |
The steadiest stretch at GTF was Before 6am — 96.2% of departures left on time across 1,490 flights. The weakest was 2–4pm at 80.5%. 6–8am departures from GTF left on time 94% of the time across 1,482 flights; 6–8pm departures, 87.5% across 935. That is a gap of 6.5 points, and it is the whole case for the early flight.
The year at GTF
February was the hard month at GTF: 86.2% of departures left on time, across 592 flights. September was the easy one at 91%. 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 | 87% | 628 |
| February | 86.2% | 592 |
| March | 90.3% | 649 |
| April | 90.9% | 606 |
| May | 88.4% | 606 |
| June | 88% | 575 |
| July | 89.9% | 627 |
| August | 89.4% | 633 |
| September | 91% | 590 |
| October | 90.4% | 596 |
| November | 90.7% | 568 |
| December | 90.5% | 590 |
Airlines at GTF
Every airline with at least 100 departures from GTF, 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 |
|---|---|---|---|---|
| SkyWest Airlines | 91.7% | 87 min | 0.4% | 5,571 |
| United Airlines | 83.3% | 93 min | 1.2% | 1,120 |
| Allegiant Air | 78.3% | 131 min | 0.4% | 569 |
What delays out of GTF were put down to
Airlines file a reason with every arrival running 15 minutes late or more. Across 897 flights that departed GTF and ran 15 minutes late or more, the delay minutes break down with 37.6% put down to airline operations and 22.5% to late-arriving aircraft.
- Late-arriving aircraft 22.5%
- Airline operations 37.6%
- Air traffic & airport volume 18.2%
- Severe weather 21.6%
- 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 GTF
Of 7,259 scheduled arrivals into GTF, 86.3% reached the gate less than 15 minutes behind schedule. Of the 955 arrivals that ran late, 54.3% 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 GTF
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.
GTF in one number
Great Falls (GTF)
Rank 184 of 363 US airports by departures. Steadiest stretch of the day: Before 6am. Hardest month: February.
Questions about GTF
- What is the best time of day to fly out of Great Falls?
- Before 6am. Departures in that band left on time 96.2% of the time across 1,490 flights, July 2023 through June 2026 — the best of the ten bands in the day. The 2–4pm band was the weakest at 80.5%.
- Is the early flight out of GTF really more reliable?
- 6–8am departures from GTF left on time 94% of the time across 1,482 flights; 6–8pm departures, 87.5% across 935. That is a gap of 6.5 points, and it is the whole case for the early flight.
- What is the worst month to fly out of GTF?
- February: 86.2% of the departures that flew left on time, with 592 scheduled. September was the other end of the year at 91%. Each figure pools three years of that calendar month.
- Which airline is most on time at GTF?
- SkyWest Airlines — 91.7% of its 5,571 departures from GTF left on time. Allegiant Air sat at the other end at 78.3% over 569 flights. Only airlines with at least 100 departures here are ranked.
- How often are flights cancelled at GTF?
- 0.5% 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.