Seattle (SEA) to San Francisco (SFO): On-Time Performance
Data through May 2026
Seattle (SEA) to San Francisco (SFO) effectively runs on two schedules. In January 2025, 87% of arrivals were on time; in May 2026 that fell to 41% — a 46-point seasonal swing. Across the full period the route averages 72% on-time against a national 78%.
- On-time
- 72%
- arrived <15 min late
- Avg delay
- 18 min
- completed flights
- Cancelled
- 1.1%
- Flights/day
- 19
- last 12 months
- Duration
- 2h 17m
- scheduled
- Distance
- 679 mi
Best airline from SEA to SFO
4 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| SkyWest Airlinesmost reliable | 78% | 13 min | 0.6% | 2,352 |
| United Airlines | 76% | 19 min | 0.9% | 4,002 |
| Delta Air Lines | 73% | 18 min | 1.3% | 1,645 |
| Alaska Airlines | 65% | 19 min | 1.3% | 5,582 |
Monthly on-time trend
Best time to fly from SEA to SFO
Aim for departures around 5 a.m. (94% on-time); avoid 8 a.m. departures (62%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 69% | 18 min |
| Tuesdaybest | 80% | 10 min |
| Wednesday | 73% | 18 min |
| Thursday | 67% | 21 min |
| Friday | 70% | 20 min |
| Saturday | 77% | 14 min |
| Sunday | 66% | 22 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft22%
- Airline operations27%
- National airspace system47%
- Weather5%
Frequently asked questions
- How often are flights from SEA to SFO delayed?
- 29% of SEA–SFO 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 18 minutes.
- Which airline is most reliable from SEA to SFO?
- SkyWest Airlines has the best on-time record on this route at 78%, based on 2,352 flights. 4 airlines flew SEA–SFO frequently enough to compare in this period.
- What is the best time of day to fly from SEA to SFO?
- Departures around 5 a.m. have the best record (94% on-time), while departures around 8 a.m. have the worst (62%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from SEA to SFO?
- The scheduled SEA–SFO flight time averages 2h 17m over 679 miles. Actual arrival times vary — flights on this route land 15+ minutes late 29% of the time.
- How often are SEA to SFO flights cancelled?
- 1.1% 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 SEA to SFO?
- May 2026 was the roughest month in this dataset, with only 41% of arrivals on time. The best was January 2025 at 87%. If your dates are flexible, that 46-point gap is worth planning around.
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Based on 13,585 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.