SFO to SEA flight delays & on-time performance
Nonstop flights from San Francisco International Airport to Seattle–Tacoma International Airport · 679 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SFO or SEA right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from San Francisco (SFO) to Seattle (SEA) arrived on time 73% of the time in Aug 2025 – Jul 2026, worse than the 78% national average.
- 1.1% were cancelled, and 8% arrived an hour or more late.
- Delta Air Lines was the most punctual airline here (81% on time); Alaska Airlines was the least (70%).
- Departures scheduled around 5am did best (95% on time); around 8am did worst (56%).
- Saturday was the most reliable day to fly (81% on time) and Thursday the least (67%).
- The largest source of delay minutes was late-arriving aircraft (47%).
Which airline is most on time from SFO to SEA?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Southwest Airlines | 100% | 0.0% | 3 min | 0.0% | 3 |
| Delta Air Lines | 81% | 1.7% | 15 min | 8.3% | 955 |
| United Airlines | 75% | 0.4% | 15 min | 7.2% | 2,053 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 70% | 1.1% | 16 min | 8.2% | 1,073 |
| Alaska Airlines | 70% | 1.3% | 18 min | 7.4% | 2,713 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am95%230 flights
- 6am91%435 flights
- 7am89%244 flights
- 8am56%231 flights
- 9am81%372 flights
- 10am64%665 flights
- 11am79%248 flights
- 12pm66%324 flights
- 1pm77%452 flights
- 2pm74%566 flights
- 3pm65%85 flights
- 4pm75%756 flights
- 5pm60%244 flights
- 6pm72%616 flights
- 7pm73%297 flights
- 8pm65%527 flights
- 9pm63%228 flights
- 10pm70%277 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday71%1.3% cancelled
- Tuesday79%0.3% cancelled
- Wednesday76%0.6% cancelled
- Thursday67%0.9% cancelled
- Friday69%2.1% cancelled
- Saturday81%1.4% cancelled
- Sunday73%0.7% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft47%
- Airline (crew, maintenance, cleaning, fueling)28%
- Air traffic control & airport congestion22%
- Extreme weather3%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)61%
- Extreme weather19%
- Air traffic control & airport congestion19%
- Security0%
SFO to SEA: common questions
- How often are SFO to SEA flights on time?
- 73% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from San Francisco to Seattle cancelled?
- 1.1% of scheduled flights were cancelled (72 of 6,797).
- How long are typical delays?
- Across all flights the average arrival delay was 16 min (early arrivals count as zero). Flights that were late arrived 57 min behind schedule on average, and 7.6% of flights were an hour or more late.
- How long is taxi time at SFO?
- Flights on this route spent 23 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SEA to SFO — 62% on time
More flights from San Francisco
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SFO → SEA, nonstop flights by US airlines that report to the DOT. How we calculate this.