Best Time to Fly SAN to DEN: On-Time Stats by Hour & Airline
San Diego International → Denver International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 79.3% of San Diego (SAN) to Denver (DEN) flights arrived on time (6,033 scheduled flights). That is 1.7 points above the national average of 77.6%.
United Airlines was the most punctual of the 5 airlines on the route at 86.1%, while Southwest Airlines trailed at 72.0%.
January has been the best month (85% on time) and Friday the weakest day of the week (71%).
0.9% of flights were cancelled, versus 1.8% nationally.
SAN 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 | 86.1% | 65 min | 0.7% | 2,074 |
| Alaska Airlines | 85.3% | 57 min | 1.0% | 495 |
| Frontier Airlines | 81.7% | 80 min | 1.4% | 705 |
| SkyWest Airlines | 75.1% | 50 min | 2.1% | 373 |
| Southwest Airlines | 72.0% | 55 min | 0.8% | 2,386 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SAN to DEN
On-time arrival % by scheduled departure hour (local time), 11,460 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | 87.7% | 1.1% | 1,535 |
| 7am–8am | 86.4% | 0.7% | 772 |
| 8am–9am | 86.5% | 0.8% | 1,001 |
| 9am–10am | 86.2% | 0.7% | 580 |
| 10am–11am | 80.0% | 0.3% | 613 |
| 11am–12pm | 83.9% | 0.6% | 897 |
| 12pm–1pm | 75.9% | 0.4% | 1,160 |
| 1pm–2pm | 64.7% | 0.2% | 538 |
| 2pm–3pm | 68.7% | 0.4% | 555 |
| 3pm–4pm | 61.5% | 1.1% | 628 |
| 4pm–5pm | 69.6% | 0.9% | 975 |
| 5pm–6pm | 67.0% | 1.3% | 310 |
| 6pm–7pm | 81.3% | 1.1% | 697 |
| 7pm–8pm | 64.8% | 0.8% | 501 |
| 8pm–9pm | 78.3% | 2.5% | 567 |
| 9pm–10pm | 76.6% | 3.9% | 129 |
| 10pm–11pm | Limited data | 2 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SAN 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) | 78.8% | -1.6 pts | 0.0% | 226 |
| Christmas & New Year (Dec 20 - Jan 3) | 71.9% | -8.4 pts | 2.7% | 487 |
| Summer peak (Jun 15 - Aug 15) | 69.1% | -11.2 pts | 0.8% | 1,980 |
| All other days | 80.3% | — | 0.8% | 8,767 |
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).