Carrier performance at one airport
AS→SFO
Alaska Airlines at San Francisco International
- Departures
- 10,629
- Period
- September 2025 to August 2026
- Routes
- 17
- Rank here
- #5 of 8
Alaska Airlines at San Francisco sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.3%. The late ones land about an hour behind schedule. That rests on 10,629 flights, of which United Airlines flew 62,048 at 79.8% on time.
Measured against the airport rather than the country, Alaska Airlines runs half a point behind the 75.3% weighted average across all carriers at SFO. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
75.0%
10,492 completed departures
Avg delay
55 min
Across delayed flights only
Cancelled
1.10%
At SFO, this carrier only
Rank here
#5
Of 8 carriers clearing the floor at SFO
These figures cover 11,000 flights between September 2025 and August 2026. The median arrival is 4 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Against the competition
Every carrier at SFO, ranked
The choice of carrier is not cosmetic here. United Airlines arrives on time 79.8% of the time; Southwest Airlines manages 54.8%. Sample sizes sit next to every figure, because a two-point gap across 9,968 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 62,048 | 79.8% | 58 min | 0.46% | B+ |
| American Airlines | 11,939 | 76.4% | 102 min | 1.84% | B |
| Delta Air Lines | 13,973 | 75.8% | 67 min | 1.29% | B |
| JetBlue Airways | 4,519 | 75.6% | 76 min | 2.21% | B |
| Alaska Airlines (this page) | 10,629 | 75.0% | 55 min | 1.10% | B |
| SkyWest Airlines | 31,536 | 73.8% | 74 min | 1.31% | C |
| Frontier Airlines | 3,581 | 62.7% | 81 min | 2.18% | D |
| Southwest Airlines | 9,968 | 54.8% | 61 min | 0.90% | F+ |
The spread between United and Southwest is 25 points, wide enough that it should decide the booking. On a hundred trips that is 25 more arrivals inside the on-time window.
Route by route
Where Alaska Airlines flies from SFO
Alaska Airlines operates 17 routes out of SFO with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SFO to SEA · Seattle | 2,729 | 68.8% | 54 min | 1.28% | C |
| SFO to PDX · Portland | 1,402 | 76.8% | 55 min | 0.57% | B+ |
| SFO to JFK · New York | 1,112 | 78.6% | 56 min | 2.16% | B |
| SFO to LAS · Las Vegas | 1,101 | 72.7% | 63 min | 0.54% | C+ |
| SFO to LAX · Los Angeles | 1,046 | 66.4% | 47 min | 0.86% | C+ |
| SFO to EWR · Newark | 487 | 89.4% | 58 min | 1.03% | A |
| SFO to HNL · Honolulu | 482 | 67.1% | 57 min | 2.90% | C |
| SFO to DCA · Washingtonthin sample | 363 | 78.3% | 51 min | 0.83% | B+ |
| SFO to SAN · San Diegothin sample | 331 | 82.9% | 44 min | 1.21% | B |
| SFO to MCO · Orlandothin sample | 278 | 83.6% | 51 min | 0.72% | B+ |
| SFO to OGG · Kahuluithin sample | 268 | 86.0% | 90 min | 1.12% | A |
| SFO to KOA · Kailua-Konathin sample | 244 | 91.4% | 63 min | 0.00% | A+ |
| SFO to LIH · Lihuethin sample | 233 | 90.0% | 47 min | 0.43% | A+ |
| SFO to AUS · Austinthin sample | 225 | 87.5% | 69 min | 0.44% | A+ |
| SFO to ANC · Anchoragethin sample | 155 | 78.7% | 40 min | 0.00% | B+ |
| SFO to BOS · Bostonthin sample | 123 | 80.3% | 63 min | 0.81% | B+ |
| SFO to SNA · Santa Anathin sample | 38 | 32.4% | 55 min | 2.63% | F |
Flight by flight
Alaska Airlines flight numbers from SFO
11 Alaska Airlines flight numbers leaving SFO flew their main route often enough to have a record of their own. Grouped by destination.
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against 25 points between the best and worst carrier.
- 5am–8am2,554 flights90.3%
- 8am–11am2,562 flights73.0%
- 11am–2pm1,246 flights61.5%
- 2pm–5pm1,346 flights69.1%
- 5pm–8pm1,759 flights71.6%
- 8pm–5am1,162 flights72.6%
Scale runs 55% to 95%.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 61.5% on time against 90.3% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 2,562 flights scheduled in it.
Across the year
Seasonal pattern
August is the worst month at 62.2% on time, 26 points below February, the best at 88.3%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. August was the busiest month here, with 1,069 flights.
Delay causes
What holds this operation up
- 48%Late-arriving aircraft
- 27%Carrier
- 24%National Airspace System
- 1%Extreme weather
- 0%Security
48% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 144,000 reported delay minutes here, that single category outweighs weather by 33 to one. The split is drawn from 143,996 reported delay minutes.
Cancellations sit at 1.10% against a national 1.89%, which is ordinary. Diversions add another 0.19%.
6.8% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
The sample behind these figures is 10,629 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 88.3% on time and August 62.2%, a swing of 26 points. If the dates move at all, move them out of August before you think about anything else. 10,492 completed flights over 12 months sit behind that.
Common questions
Alaska Airlines at SFO
How often is Alaska Airlines at SFO delayed?
About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 25.0% of the 10,629 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on Alaska Airlines at SFO?
United Airlines leads at 79.8% on time across 62,048 flights. Southwest Airlines is at the other end on 54.8%, a gap of 25 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on Alaska Airlines at SFO?
The 5am–8am departure window is the strongest at 90.3% on time. The 11am–2pm window is the weakest at 61.5%, 29 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are August delays on Alaska Airlines at SFO?
August is the weakest month at 62.2% on time, compared with 88.3% in February. Across the year that is 26 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.