SFO → DEN Flight Reliability

Right now

Origin · SFONo disruption reported

Aviation weather is not currently a factor.

Updated 08:56 UTC

San Francisco airport profile →

Destination · DENNo disruption reported

Aviation weather is not currently a factor.

Updated 08:53 UTC

Denver airport profile →

Route reliability

July 2023 – July 2026

Route Reliability Score

66/ 100Good

Better than 51% of comparable major US routes (4,598 compared)

Calculated from 17,119 flights. How this is calculated

On-time arrivals

76.4%

12,959 of 16,968

Cancellation rate

0.62%

106 cancelled

Median arrival delay

-5 min

Average 7.9 min

Severe delays

7.9%

60+ minutes late

Delay when late

63 min

Average, when 15+ min late

Flights analyzed

17,119

3 carriers

SFO → DEN arrives on time 76.4% of the time; the return trip, DEN → SFO, arrives on time 67.8% of the time, an 8.6-point gap between the two directions of the same city pair.

SFO → DEN spends 29.0 minutes on the ground on a 967-mile trip: 19.4 minutes from pushback to wheels-up at SFO and 9.6 minutes from touchdown to gate at DEN.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

What stands out

On-time performance swings unusually widely by time of day here, wider than 98% of 4,023 comparable routes.

90.6% on time for 5–9 AM departures, against 54.4% for 9 PM–5 AM.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,023 in the comparison.

Why SFO → DEN flights are cancelled

July 2023 – July 2026

SFO → DEN cancelled 106 of 17,119 scheduled flights — about 1 in every 162. The reason filed most often was the airline, 63.2% of the cancellations coded on this route — about 1 in every 256 scheduled flights.

Share of cancellations

Airline63.2%

Weather27.4%

Air traffic9.4%

Security0.0%

Of 106 cancelled departures carrying a reason code.

What each reason means

The airline1 in 256

Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.

67 cancellations, 63.2% of the total.

Extreme weather1 in 590

Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.

29 cancellations, 27.4% of the total.

The air traffic system1 in 1,712

Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.

10 cancellations, 9.4% of the total.

Security—

A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.

0 cancellations, 0.0% of the total.

Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.

106 coded cancellations were recorded on SFO → DEN; the section appears from 50.

When it goes wrong

July 2023 – July 2026

One arrival in ten is worse than

48 min late

against a median of 5 min early

Arrived an hour or more late7.9%

Typical delay when late63 min

Cancelled0.62%

Landed somewhere else0.26%

Percentiles over 17,119 operations; cancelled and diverted flights are counted separately.

Will your connection be tight enough?

Layovers at DEN after arriving from SFO.

Connection buffer and chance of missing by layover length, SFO → DEN arrivals
Connection time	Chance of missing	Reads as
30 min	39%	Likely to miss
45 min	23%	High risk
60 min	15%	Some risk
90 min	7.7%	Some risk
120 min	4.6%	Low risk

This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.62% of the time and diverts 0.26% of the time, which a late arrival never shows up in.

Chance of missing is the share of 16,968 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.

The worst tenth of arrivals on this route land at least 48 minutes late (90th-percentile gate arrival delay), over 17,119 operations.

Any other layover length: connection checker.

Best time to fly

SFO → DEN flights departing 5–9 AM arrived on time 90.6% of the time, against 54.4% for 9 PM–5 AM departures, a gap of 36.2 percentage points.

By day and hour

On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (SFO).

Hour of departure matters more than day of the week: hourly averages sit a typical 12.1 points from the route-wide rate, weekday averages 2.4 points.

On-time arrival rate for SFO to DEN by weekday and scheduled departure hour, local time. Each button reads out one slot.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
5 AM–6 AM
6 AM–7 AM
7 AM–8 AM
8 AM–9 AM
9 AM–10 AM
10 AM–11 AM
11 AM–12 PM
12 PM–1 PM
1 PM–2 PM
2 PM–3 PM
3 PM–4 PM
4 PM–5 PM
5 PM–6 PM
6 PM–7 PM
7 PM–8 PM
8 PM–9 PM

On-time rate, % · stronger color, fewer on time

50–59
60–69
70–79
80–89
90–99

Fewer than 120 flights, not scored

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.

No slot is named best or worst: too few reach 500 flights. Departures before 5 AM and after 9 PM (558 flights) are not drawn: no slot in those hours has enough flights to score.

View as tableHide table

On-time arrival rate (%) with flights beneath, by scheduled departure hour and weekday for SFO to DEN. A dash means fewer than 120 flights, which are not scored.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
5 AM–6 AM	96.1% on time308 flights	95.2% on time272 flights	94.4% on time268 flights	94.5% on time313 flights	96.1% on time314 flights	93.8% on time298 flights	94.9% on time313 flights
6 AM–7 AM	89.5% on time292 flights	88.1% on time287 flights	89.5% on time288 flights	91.0% on time290 flights	88.9% on time288 flights	88.9% on time273 flights	91.7% on time289 flights
7 AM–8 AM	15 flights, too few to score	40 flights, too few to score	39 flights, too few to score	23 flights, too few to score	18 flights, too few to score	10 flights, too few to score	37 flights, too few to score
8 AM–9 AM	88.1% on time296 flights	89.4% on time236 flights	88.6% on time228 flights	84.7% on time288 flights	78.2% on time293 flights	89.0% on time181 flights	88.8% on time190 flights
9 AM–10 AM	23 flights, too few to score	35 flights, too few to score	34 flights, too few to score	22 flights, too few to score	23 flights, too few to score	66 flights, too few to score	53 flights, too few to score
10 AM–11 AM	41 flights, too few to score	56 flights, too few to score	58 flights, too few to score	47 flights, too few to score	47 flights, too few to score	114 flights, too few to score	81 flights, too few to score
11 AM–12 PM	71.5% on time198 flights	72.4% on time198 flights	65.6% on time194 flights	72.5% on time195 flights	76.3% on time195 flights	68.1% on time140 flights	72.4% on time166 flights
12 PM–1 PM	57.7% on time166 flights	67.6% on time171 flights	65.3% on time180 flights	67.3% on time169 flights	63.8% on time165 flights	67.5% on time169 flights	68.9% on time163 flights
1 PM–2 PM	100 flights, too few to score	68.5% on time125 flights	117 flights, too few to score	96 flights, too few to score	101 flights, too few to score	112 flights, too few to score	94 flights, too few to score
2 PM–3 PM	61.4% on time224 flights	71.4% on time242 flights	67.5% on time259 flights	60.3% on time234 flights	57.2% on time218 flights	74.3% on time176 flights	67.7% on time203 flights
3 PM–4 PM	85 flights, too few to score	70 flights, too few to score	68 flights, too few to score	85 flights, too few to score	88 flights, too few to score	60 flights, too few to score	92 flights, too few to score
4 PM–5 PM	71.7% on time166 flights	78.3% on time167 flights	74.4% on time167 flights	67.0% on time180 flights	71.2% on time163 flights	78.7% on time150 flights	70.8% on time168 flights
5 PM–6 PM	74 flights, too few to score	70 flights, too few to score	68 flights, too few to score	76 flights, too few to score	78 flights, too few to score	52 flights, too few to score	56 flights, too few to score
6 PM–7 PM	112 flights, too few to score	103 flights, too few to score	101 flights, too few to score	99 flights, too few to score	108 flights, too few to score	108 flights, too few to score	99 flights, too few to score
7 PM–8 PM	66.1% on time219 flights	87.2% on time150 flights	74.8% on time152 flights	64.1% on time208 flights	65.0% on time217 flights	118 flights, too few to score	74.5% on time153 flights
8 PM–9 PM	75.9% on time159 flights	102 flights, too few to score	116 flights, too few to score	71.2% on time147 flights	72.8% on time170 flights	103 flights, too few to score	72.6% on time177 flights

By departure window

5–9 AM90.6%

9 AM–12 PM68.9%

12–3 PM64.5%

3–6 PM69.3%

6–9 PM75.9%

9 PM–5 AM54.4%

By departure hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Why SFO → DEN runs late

July 2023 – July 2026

Late-arriving aircraft53.7%

the inbound aircraft was late, so this flight started late

The airline26.5%

crew, maintenance, boarding and fueling, all within the carrier’s control

Air traffic control18.6%

airspace and airport capacity, including weather-driven flow control

Weather1.2%

weather severe enough to stop this flight specifically

Security<0.1%

screening or terminal security incidents

Share of the delay minutes US DOT attributed to each cause for SFO → DEN. Only delays of 15 minutes or more are attributed.

Late-arriving aircraft is the largest cause on SFO → DEN, at 53.7%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 90.6% of the time and 9 PM–5 AM departures 54.4%.

How this route holds up in bad weather

July 2023 – July 2026

The harder-hit end is DEN, where the flight lands. Its figure counts departures from DEN, so it says more about how that airport copes than about this route. Bad weather cancels 4.0 times the normal rate at DEN against 1.7 times at SFO. Cancelled in bad weather against normal hours: SFO 1.5% against 0.9%, DEN 2.8% against 0.7%. Flights that did leave DEN in bad weather arrived on time 51.5% of the time, against 78.8% in normal hours.

Bad weather and normal hours at the airports

Scheduled departures, July 2023 – July 2026

Departures from SFO and DEN in hours of bad weather and in normal hours
Departures from	SFO	DEN
Cancelled in bad weather	1.5%	2.8%
Cancelled in normal hours	0.9%	0.7%
Arrived on time, bad weather	73.0%	51.5%
Arrived on time, normal hours	79.8%	78.8%
Departures in bad weather	36,006	92,610

United Airlines (1.0% cancelled against 1.9% for the other carriers at SFO) cancelled fewer departures from SFO in bad weather than the other carriers there did in the same months. None of the route’s other carriers was clearly worse.

This route’s airlines in bad weather at SFO

All departures from SFO

Cancellation rates in bad weather at SFO for the airlines that fly SFO to DEN, against the other carriers at SFO in the same months
Airline	Bad-weather departures	Cancelled	Other carriers
United Airlines	13,903	1.0%below the others	1.9%
Southwest Airlines	2,224	1.1%about level	1.5%
Frontier Airlines	1,057	1.8%about level	1.5%

These are airport figures, not route figures: every scheduled departure from SFO and DEN, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from SFO on every route.

Weather source and limits. In full: SFO (airlines), DEN, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.

Airlines on this route

Carriers with at least 200 flights, by the airline that operated each one.

Airlines on this route
Carrier	Flights	On time	Cancelled	Median delay	Severe
United Airlines	10,398	82.5%	0.53%	-8 min	5.8%
Southwest Airlines	4,712	66.3%	0.62%	3 min	10.3%
Frontier Airlines	2,009	68.3%	1.10%	-1 min	12.8%

United Airlines flew 60.7% of the 17,119 flights listed.

United Airlines arrived on time 16.2 percentage points more often than Southwest Airlines on this route.

Flights on this route

Flight numbers with at least 600 operations here and still on the schedule.

Flights on this route
Flight	Scheduled	Operations	On time
F91230 Frontier Airlines	6:00 AM	765	83.4%

Weekly and seasonal patterns

By day of week

Mon74.6%

Tue80.3%

Wed77.1%

Thu74.4%

Fri73.4%

Sat79.2%

Sun76.3%

Tuesday is historically the most reliable day and Friday the least, a gap of 6.9 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

May is historically the weakest month and January the strongest, a spread of 13.4 percentage points.

Reliability over time

July 2023 – July 2026

24

25

26

Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 75.3% against 78.5% in the 12 months before — declining by 3.2 percentage points.

Data and methodology

Calculated by FlyerIntel from 17,119 SFO → DEN flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.

Full methodology · Data sources · Report a problem

Analysis last recomputed September 26, 2026

SFO airport DEN airport Return direction DEN → SFO

SFO→DEN

Right now

Route reliability

What stands out

Why SFO → DEN flights are cancelled

Share of cancellations

What each reason means

When it goes wrong

Will your connection be tight enough?

Best time to fly

By day and hour

By departure window

By departure hour

Why SFO → DEN runs late

How this route holds up in bad weather

Bad weather and normal hours at the airports

This route’s airlines in bad weather at SFO

Airlines on this route

Flights on this route

Weekly and seasonal patterns

By day of week

By month

Reliability over time

Data and methodology