Denver (DEN) to San Diego (SAN): On-Time Performance
Data through July 2026
The calendar drives reliability on DEN–SAN. February 2026 flights landed on schedule 84% of the time, but July 2026 dropped to 64% — a gap of 20 points. Across the full period the route averages 75% on-time against a national 78%. Morning departures also hold up better than evening ones (84% vs 63%), which matters most in the rough months.
- On-time
- 75%
- arrived <15 min late
- Avg delay
- 15 min
- completed flights
- Cancelled
- 0.8%
- Flights/day
- 17
- last 12 months
- Duration
- 2h 28m
- scheduled
- Distance
- 853 mi
Best airline from DEN to SAN
5 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Alaska Airlinesmost reliable | 83% | 10 min | 1.2% | 495 |
| United Airlines | 79% | 13 min | 0.5% | 4,416 |
| Frontier Airlines | 76% | 17 min | 1.3% | 1,678 |
| Southwest Airlines | 71% | 17 min | 0.7% | 4,984 |
| SkyWest Airlines | 71% | 14 min | 1.6% | 374 |
Monthly on-time trend
Best time to fly from DEN to SAN
Aim for departures around 5 a.m. (90% on-time); avoid 8 p.m. departures (59%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 75% | 14 min |
| Tuesday | 79% | 14 min |
| Wednesday | 78% | 13 min |
| Thursday | 70% | 19 min |
| Friday | 72% | 19 min |
| Saturdaybest | 80% | 10 min |
| Sunday | 73% | 15 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft44%
- Airline operations28%
- National airspace system25%
- Weather3%
Frequently asked questions
- How often are flights from DEN to SAN delayed?
- 25% of DEN–SAN flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 15 minutes.
- Which airline is most reliable from DEN to SAN?
- Alaska Airlines has the best on-time record on this route at 83%, based on 495 flights. 5 airlines flew DEN–SAN frequently enough to compare in this period.
- What is the best time of day to fly from DEN to SAN?
- Departures around 5 a.m. have the best record (90% on-time), while departures around 8 p.m. have the worst (59%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from DEN to SAN?
- The scheduled DEN–SAN flight time averages 2h 28m over 853 miles. Actual arrival times vary — flights on this route land 15+ minutes late 25% of the time.
- How often are DEN to SAN flights cancelled?
- 0.8% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What is the worst month to fly from DEN to SAN?
- July 2026 was the roughest month in this dataset, with only 64% of arrivals on time. The best was February 2026 at 84%. If your dates are flexible, that 20-point gap is worth planning around.
Explore related pages
More routes from DEN
Other ways to fly to San Diego (SAN)
Related guides
Based on 11,947 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.