SMF → DEN Flight Reliability

Right now

Origin · SMFNo disruption reported

Aviation weather is not currently a factor.

Updated 09:53 UTC

Sacramento airport profile →

Destination · DENNo disruption reported

Aviation weather is not currently a factor.

Updated 09:53 UTC

Denver airport profile →

Route reliability

July 2023 – July 2026

Route Reliability Score

79/ 100Strong

Better than 86% of comparable major US routes (4,598 compared)

Calculated from 12,215 flights. How this is calculated

On-time arrivals

83.6%

10,116 of 12,096

Cancellation rate

0.62%

76 cancelled

Median arrival delay

-7 min

Average 2.4 min

Severe delays

5.2%

60+ minutes late

Delay when late

59 min

Average, when 15+ min late

Flights analyzed

12,215

3 carriers

SMF → DEN arrives on time 83.6% of the time; the return trip, DEN → SMF, arrives on time 74.5% of the time, a 9.2-point gap between the two directions of the same city pair.

SMF → DEN spends 20.9 minutes on the ground on a 909-mile trip: 12.4 minutes from pushback to wheels-up at SMF and 8.5 minutes from touchdown to gate at DEN.

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

What stands out

This route has stayed remarkably steady year over year, a smaller swing than 98% of 5,368 comparable routes.

83.3% on time over the most recent 12 months (2025-08 to 2026-07), against 83.2% in the 12 months before (2024-08 to 2025-07), virtually unchanged.

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 5,368 in the comparison.

Why SMF → DEN flights are cancelled

July 2023 – July 2026

SMF → DEN cancelled 76 of 12,215 scheduled flights — about 1 in every 161. The reason filed most often was the airline, 63.2% of the cancellations coded on this route — about 1 in every 254 scheduled flights.

Share of cancellations

Airline63.2%

Weather26.3%

Air traffic10.5%

Security0.0%

Of 76 cancelled departures carrying a reason code.

What each reason means

The airline1 in 254

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

48 cancellations, 63.2% of the total.

Extreme weather1 in 611

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

20 cancellations, 26.3% of the total.

The air traffic system1 in 1,527

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

8 cancellations, 10.5% 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.

76 coded cancellations were recorded on SMF → DEN; the section appears from 50.

When it goes wrong

July 2023 – July 2026

One arrival in ten is worse than

31 min late

against a median of 7 min early

Arrived an hour or more late5.2%

Typical delay when late59 min

Cancelled0.62%

Landed somewhere else0.35%

Percentiles over 12,215 operations; cancelled and diverted flights are counted separately.

Will your connection be tight enough?

Layovers at DEN after arriving from SMF.

Connection buffer and chance of missing by layover length, SMF → DEN arrivals
Connection time	Chance of missing	Reads as
30 min	33%	Likely to miss
45 min	16%	High risk
60 min	10%	Some risk
90 min	5.0%	Some risk
120 min	2.8%	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 0.35% of the time, which a late arrival never shows up in.

Chance of missing is the share of 12,096 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 31 minutes late (90th-percentile gate arrival delay), over 12,215 operations.

Any other layover length: connection checker.

Best time to fly

SMF → DEN flights departing 5–9 AM arrived on time 93.9% of the time, against 64.6% for 9 PM–5 AM departures, a gap of 29.3 percentage points.

By day and hour

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

Hour of departure matters more than day of the week: hourly averages sit a typical 9.1 points from the route-wide rate, weekday averages 1.3 points.

On-time arrival rate for SMF 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

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

72–75
76–79
80–83
84–87
88–91
92–95
96–99

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 after 7 PM (934 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 SMF 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	96.4% on time282 flights	98.8% on time248 flights	96.3% on time246 flights	95.3% on time283 flights	91.3% on time289 flights	95.3% on time280 flights	94.8% on time269 flights
6 AM–7 AM	69 flights, too few to score	68 flights, too few to score	69 flights, too few to score	68 flights, too few to score	62 flights, too few to score	48 flights, too few to score	46 flights, too few to score
7 AM–8 AM	23 flights, too few to score	37 flights, too few to score	37 flights, too few to score	15 flights, too few to score	18 flights, too few to score	9 flights, too few to score	28 flights, too few to score
8 AM–9 AM	94.2% on time191 flights	91.6% on time215 flights	94.4% on time217 flights	93.8% on time197 flights	90.2% on time193 flights	94.4% on time182 flights	93.8% on time195 flights
9 AM–10 AM	69 flights, too few to score	63 flights, too few to score	59 flights, too few to score	62 flights, too few to score	64 flights, too few to score	92 flights, too few to score	91 flights, too few to score
10 AM–11 AM	88.1% on time171 flights	85.4% on time131 flights	90.5% on time126 flights	89.3% on time170 flights	87.9% on time175 flights	108 flights, too few to score	110 flights, too few to score
11 AM–12 PM	63 flights, too few to score	33 flights, too few to score	51 flights, too few to score	46 flights, too few to score	77 flights, too few to score	43 flights, too few to score	46 flights, too few to score
12 PM–1 PM	87.1% on time149 flights	75.9% on time140 flights	79.6% on time137 flights	82.9% on time126 flights	78.3% on time140 flights	78.1% on time130 flights	76.0% on time129 flights
1 PM–2 PM	75.1% on time171 flights	78.6% on time160 flights	78.6% on time156 flights	78.9% on time174 flights	75.7% on time173 flights	82.2% on time130 flights	79.5% on time153 flights
2 PM–3 PM	67 flights, too few to score	68 flights, too few to score	71 flights, too few to score	59 flights, too few to score	55 flights, too few to score	32 flights, too few to score	73 flights, too few to score
3 PM–4 PM	91 flights, too few to score	72 flights, too few to score	70 flights, too few to score	96 flights, too few to score	97 flights, too few to score	52 flights, too few to score	66 flights, too few to score
4 PM–5 PM	74.2% on time189 flights	76.8% on time182 flights	77.5% on time180 flights	74.9% on time185 flights	76.8% on time196 flights	82.5% on time178 flights	81.0% on time176 flights
5 PM–6 PM	55 flights, too few to score	29 flights, too few to score	32 flights, too few to score	54 flights, too few to score	65 flights, too few to score	42 flights, too few to score	50 flights, too few to score
6 PM–7 PM	79.9% on time139 flights	119 flights, too few to score	78.6% on time170 flights	78.1% on time131 flights	82.4% on time128 flights	70 flights, too few to score	76.6% on time140 flights

By departure window

5–9 AM93.9%

9 AM–12 PM89.4%

12–3 PM76.8%

3–6 PM74.5%

6–9 PM77.2%

9 PM–5 AM64.6%

By departure hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Why SMF → DEN runs late

July 2023 – July 2026

Late-arriving aircraft44.2%

the inbound aircraft was late, so this flight started late

Air traffic control28.9%

airspace and airport capacity, including weather-driven flow control

The airline25.2%

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

Weather1.5%

weather severe enough to stop this flight specifically

Security0.1%

screening or terminal security incidents

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

Late-arriving aircraft is the largest cause on SMF → DEN, at 44.2%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 93.9% of the time and 9 PM–5 AM departures 64.6%.

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 1.6 times at SMF. Cancelled in bad weather against normal hours: SMF 1.0% against 0.6%, 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 SMF and DEN in hours of bad weather and in normal hours
Departures from	SMF	DEN
Cancelled in bad weather	1.0%	2.8%
Cancelled in normal hours	0.6%	0.7%
Arrived on time, bad weather	83.0%	51.5%
Arrived on time, normal hours	83.2%	78.8%
Departures in bad weather	12,018	92,610

None of the 2 carriers on this route stood clearly apart from the other carriers at SMF in bad weather. One more carrier flies this route but has too few bad-weather departures from SMF to compare.

This route’s airlines in bad weather at SMF

All departures from SMF

Cancellation rates in bad weather at SMF for the airlines that fly SMF to DEN, against the other carriers at SMF in the same months
Airline	Bad-weather departures	Cancelled	Other carriers
United Airlines	942	0.6%about level	1.1%
Southwest Airlines	6,823	1.0%about level	1.2%

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

Weather source and limits. In full: SMF (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
Southwest Airlines	5,959	79.2%	0.49%	-2 min	5.7%
United Airlines	5,724	88.9%	0.77%	-11 min	4.3%
Frontier Airlines	528	76.3%	0.57%	-5 min	8.8%

Southwest Airlines flew 48.8% of the 12,211 flights listed.

United Airlines arrived on time 12.6 percentage points more often than Frontier 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
UA2285 United Airlines	8:45 AM	1,056	94.2%

Weekly and seasonal patterns

By day of week

Mon82.5%

Tue84.7%

Wed85.3%

Thu82.6%

Fri81.9%

Sat85.3%

Sun83.6%

Wednesday is historically the most reliable day and Friday the least, a gap of 3.4 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

July is historically the weakest month and October the strongest, a spread of 14.4 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 83.3% against 83.2% in the 12 months before — broadly unchanged.

Data and methodology

Calculated by FlyerIntel from 12,215 SMF → 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

SMF airport DEN airport Return direction DEN → SMF

SMF→DEN

Right now

Route reliability

What stands out

Why SMF → 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 SMF → 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 SMF

Airlines on this route

Flights on this route

Weekly and seasonal patterns

By day of week

By month

Reliability over time

Data and methodology