FlightRecord

San Francisco (SFO) to Denver (DEN): On-Time Performance

Data through May 2026

San Francisco (SFO) to Denver (DEN) effectively runs on two schedules. In September 2024, 89% of arrivals were on time; in July 2025 that fell to 66% — a 23-point seasonal swing. Across the full period the route averages 78% on-time against a national 78%. Morning departures also hold up better than evening ones (87% vs 77%), which matters most in the rough months.

On-time
78%
arrived <15 min late
Avg delay
15 min
completed flights
Cancelled
0.5%
Flights/day
15
last 12 months
Duration
2h 37m
scheduled
Distance
967 mi

Best airline from SFO to DEN

3 airlines flew this route regularly between 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
United Airlinesmost reliable83%11 min0.3%6,830
Frontier Airlines72%24 min1.1%1,270
Southwest Airlines68%19 min0.5%3,017

Monthly on-time trend

Monthly on-time percentage for SFO to DEN flights50%75%100%June 2024: 74% on-time (460 flights)74Jun 2024July 2024: 77% on-time (477 flights)77August 2024: 77% on-time (481 flights)77September 2024: 89% on-time (486 flights)89Sep 2024October 2024: 83% on-time (495 flights)83November 2024: 77% on-time (489 flights)77December 2024: 80% on-time (506 flights)80Dec 2024January 2025: 83% on-time (477 flights)83February 2025: 82% on-time (439 flights)82March 2025: 83% on-time (470 flights)83Mar 2025April 2025: 83% on-time (463 flights)83May 2025: 68% on-time (490 flights)68June 2025: 69% on-time (468 flights)69Jun 2025July 2025: 66% on-time (463 flights)66August 2025: 71% on-time (460 flights)71September 2025: 74% on-time (450 flights)74Sep 2025October 2025: 81% on-time (460 flights)81November 2025: 77% on-time (437 flights)77December 2025: 74% on-time (456 flights)74Dec 2025January 2026: 87% on-time (435 flights)87February 2026: 83% on-time (398 flights)83March 2026: 83% on-time (448 flights)83Mar 2026April 2026: 75% on-time (426 flights)75May 2026: 71% on-time (483 flights)71

Best time to fly from SFO to DEN

Aim for departures around 5 a.m. (95% on-time); avoid 12 a.m. departures (36%).

On-time percentage by scheduled departure hour, SFO to DEN5 a.m.: 95% on-time (1,317 flights)56 a.m.: 89% on-time (1,416 flights)67 a.m.: 90% on-time (151 flights)78 a.m.: 88% on-time (1,121 flights)89 a.m.: 79% on-time (174 flights)910 a.m.: 67% on-time (219 flights)1011 a.m.: 74% on-time (792 flights)1112 p.m.: 66% on-time (833 flights)121 p.m.: 60% on-time (523 flights)132 p.m.: 67% on-time (1,012 flights)143 p.m.: 56% on-time (371 flights)154 p.m.: 73% on-time (801 flights)165 p.m.: 73% on-time (247 flights)176 p.m.: 84% on-time (508 flights)187 p.m.: 72% on-time (735 flights)198 p.m.: 82% on-time (604 flights)209 p.m.: 71% on-time (217 flights)21scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday77%15 min
Tuesdaybest81%12 min
Wednesday79%15 min
Thursday75%18 min
Friday75%17 min
Saturday81%13 min
Sunday78%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 aircraft49%
  • Airline operations28%
  • National airspace system22%
  • Weather1%

Frequently asked questions

How often are flights from SFO to DEN delayed?
22% of SFO–DEN flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 15 minutes.
Which airline is most reliable from SFO to DEN?
United Airlines has the best on-time record on this route at 83%, based on 6,830 flights. 3 airlines flew SFO–DEN frequently enough to compare in this period.
What is the best time of day to fly from SFO to DEN?
Departures around 5 a.m. have the best record (95% on-time), while departures around 12 a.m. have the worst (36%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from SFO to DEN?
The scheduled SFO–DEN flight time averages 2h 37m over 967 miles. Actual arrival times vary — flights on this route land 15+ minutes late 22% of the time.
How often are SFO to DEN flights cancelled?
0.5% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from SFO to DEN?
July 2025 was the roughest month in this dataset, with only 66% of arrivals on time. The best was September 2024 at 89%. If your dates are flexible, that 23-point gap is worth planning around.

Based on 11,117 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.