Best Time to Fly BUF to DEN: On-Time Stats by Hour & Airline
Buffalo Niagara International → Denver International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 74.9% of Buffalo (BUF) to Denver (DEN) flights arrived on time (586 scheduled flights). That is 2.8 points below the national average of 77.6%.
Among 3 airlines, United Airlines led with 84.3% on time and Frontier Airlines was last with 62.9%.
Over 24 months, Thursday was the most reliable day (83% on time) and February the worst month (69%).
The cancellation rate was 0.2% (US average 1.8%).
BUF to DEN on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 84.3% | 72 min | 0.0% | 293 |
| Southwest Airlines | 65.8% | 50 min | 0.4% | 258 |
| Frontier Airlines | 62.9% | 45 min | 0.0% | 35 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly BUF to DEN
On-time arrival % by scheduled departure hour (local time), 1,065 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 90.6% | 0.0% | 64 |
| 6am–7am | 84.2% | 0.0% | 38 |
| 7am–8am | 89.4% | 0.0% | 113 |
| 8am–9am | 85.6% | 0.3% | 327 |
| 9am–10am | 84.5% | 0.0% | 71 |
| 10am–11am | 84.3% | 1.4% | 71 |
| 11am–12pm | 95.0% | 0.0% | 40 |
| 12pm–1pm | 81.8% | 0.0% | 44 |
| 1pm–2pm | Limited data | 12 | |
| 2pm–3pm | 70.0% | 0.0% | 50 |
| 3pm–4pm | 60.0% | 0.0% | 31 |
| 4pm–5pm | 47.1% | 0.0% | 119 |
| 5pm–6pm | 52.2% | 0.0% | 46 |
| 6pm–7pm | Limited data | 4 | |
| 7pm–8pm | Limited data | 21 | |
| 8pm–9pm | Limited data | 6 | |
| 9pm–10pm | Limited data | 8 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on BUF to DEN
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | Limited data | 23 | ||
| Christmas & New Year (Dec 20 - Jan 3) | Limited data | 25 | ||
| Summer peak (Jun 15 - Aug 15) | 76.6% | -3.1 pts | 0.3% | 297 |
| All other days | 79.7% | — | 0.0% | 720 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).