Route Reliability

Route reliability

Denver (DEN) to San Francisco (SFO): which airline is most on time?

On-time arrivals, cancellations and long delays for every airline that reported nonstop flights from Denver, CO (DEN) to San Francisco, CA (SFO), September 2025 to August 2026.

Historical performance Official DOT data through August 2026 · Not live flight status

Denver, COSan Francisco, CA

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Three-letter airport codes, nonstop U.S. domestic flights. One direction at a time.

Route at a glance · September 2025 to August 2026

DEN to SFO

Denver, CO to San Francisco, CA

On time
62.9%vs 75.6% U.S. average Worse than average
Cancelled
0.4%vs 1.9% U.S. average Better than average
60+ min late
13.3%vs 8.1% U.S. average Worse than average
Scheduled flights
5,488in 12 months3 airlines
Most reliable airline
United Airlines68.9% on time · 3,429 flights

On time less often than the U.S. average, with fewer cancellations.

Compared with all U.S. flights, September 2025 to August 2026. “About average” means within 1.5 points for on time, 0.3 for cancelled and 1 for 60+ minutes late.

Airlines on this route

Ranked by on-time arrival

Airlines from DEN to SFO, September 2025 to August 2026. Rates are shares of all scheduled flights.
Airline On time Cancelled 60+ min late Avg delay when late Diverted Flights
1. United Airlines Most reliable 68.9% 0.2% 10.4% 62 min 0.0% 3,429
2. Frontier Airlines 63.3% 1.0% 11.1% 60 min 0.1% 667
3. Southwest Airlines 48.1% 0.5% 21.5% 61 min 0.1% 1,392

On time = arrived within 15 minutes of schedule. Avg delay when late = average arrival delay of flights 15+ minutes late. "Most reliable" needs at least 300 flights in 12 months. Tap a heading to sort.

What this means

United Airlines has the strongest record on this route.

  • United Airlines had the best on-time record from Denver (DEN) to San Francisco (SFO): 68.9% of its 3,429 scheduled flights arrived within 15 minutes of schedule, compared with 48.1% for Southwest Airlines.
  • 0.4% of flights on this route were cancelled, 1.5 points lower than the U.S. average of 1.9%.
  • 13.3% of flights, about 1 in 8, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 62 min.
  • Overall, 62.9% of flights on this route arrived on time, 12.7 points lower than the U.S. average of 75.6%.
  • Over the last 3 years, October was the most reliable month on this route (77.8% on time) and June the least reliable (55.7%).
  • Cancellations peaked in January, when 2.2% of flights were cancelled.
  • Flights scheduled to depart before 6 am were the most punctual (95.3% on time); flights scheduled to depart 9 am to 10 am were the least (41.5%).
  • In the other direction, San Francisco (SFO) to Denver (DEN), 74.0% of flights were on time and 0.5% were cancelled. Compare airlines SFO to DEN.

Best and worst months to fly DEN to SFO

Jan 74.3%
Feb 61.7%
Mar 68.1%
Apr 64.0%
May 59.7%
Jun 55.7%
Jul 56.2%
Aug 63.4%
Sep 77.7%
Oct 77.8%
Nov 73.0%
Dec 72.5%
Share of scheduled flights on time 12-month average 62.9%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 74.3% 1,309
February 61.7% 1,213
March 68.1% 1,368
April 64.0% 1,344
May 59.7% 1,448
June 55.7% 1,423
July 56.2% 1,456
August 63.4% 1,427
September 77.7% 1,405
October 77.8% 1,416
November 73.0% 1,389
December 72.5% 1,435
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
United Airlines September (84.0%) July (62.1%)
Frontier Airlines December (82.2%) July (43.2%)
Southwest Airlines October (68.9%) June (41.5%)

Month by month, last 12 months

Sep 74.3%
Oct 70.9%
Nov 69.3%
Dec 63.9%
Jan 80.7%
Feb 74.4%
Mar 81.5%
Apr 59.4%
May 53.4%
Jun 39.3%
Jul 43.8%
Aug 52.3%
Share of scheduled flights on time U.S. average 75.6%
All airlines combined, September 2025 to August 2026. Scale starts at zero.
Show as table
PeriodOn timeFlights
Sep 2025 74.3% 451
Oct 2025 70.9% 460
Nov 2025 69.3% 437
Dec 2025 63.9% 457
Jan 2026 80.7% 435
Feb 2026 74.4% 399
Mar 2026 81.5% 448
Apr 2026 59.4% 426
May 2026 53.4% 483
Jun 2026 39.3% 494
Jul 2026 43.8% 514
Aug 2026 52.3% 484

Best and worst departure times

<6a 95.3%
6a 94.9%
7a 64.6%
8a 62.5%
9a 41.5%
10a 80.0%
11a 62.6%
12p 49.6%
1p 70.6%
2p 59.7%
3p 68.4%
4p 62.2%
5p 66.6%
6p 47.4%
7p 43.0%
8p 51.3%
9p 54.8%
10p 66.6%
11p Insufficient sample
Share of scheduled flights on time
By scheduled local departure hour at DEN, September 2025 to August 2026. Hours with no scheduled flights are omitted. Scale starts at zero.
Show as table
PeriodOn timeFlights
Departing before 6 am 95.3% 256
Departing 6 am to 7 am 94.9% 274
Departing 7 am to 8 am 64.6% 441
Departing 8 am to 9 am 62.5% 256
Departing 9 am to 10 am 41.5% 378
Departing 10 am to 11 am 80.0% 125
Departing 11 am to noon 62.6% 447
Departing noon to 1 pm 49.6% 121
Departing 1 pm to 2 pm 70.6% 470
Departing 2 pm to 3 pm 59.7% 62
Departing 3 pm to 4 pm 68.4% 434
Departing 4 pm to 5 pm 62.2% 135
Departing 5 pm to 6 pm 66.6% 374
Departing 6 pm to 7 pm 47.4% 211
Departing 7 pm to 8 pm 43.0% 416
Departing 8 pm to 9 pm 51.3% 275
Departing 9 pm to 10 pm 54.8% 467
Departing 10 pm to 11 pm 66.6% 344
Departing 11 pm to midnight Insufficient sample 2
Woman at an airport window watching a plane take off
Photo: Depositphotos (licensed stock, illustrative only). Credits

Sources & data dates

Source
U.S. DOT Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987-present)
Period
September 2025 to August 2026 (12 months); month-of-year patterns September 2023 to August 2026
Data through
August 2026
Processed
2026-11-03
Scope
Nonstop scheduled flights from Denver, CO (DEN) to San Francisco, CA (SFO), one direction. Airlines that report to the DOT only.
Method
Rates use all scheduled flights as the denominator; cancelled and diverted flights count as not on time. Figures based on fewer than 50 scheduled flights are suppressed. Full methodology.

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