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Route on-time record

SFO to SEA: most on-time flights and the best time to fly

San Francisco (San Francisco International Airport) to Seattle (Seattle–Tacoma International Airport). 6,768 nonstop flights in Jun 2025 to May 2026, 74% arrived within 15 minutes and 1.2% were cancelled. The most reliable flight number was Delta 2721 at 5:55 AM.

Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.

SFO → SEA

San Francisco to Seattle: 6,768 nonstop flights a year

On time (12 months)

74%

Cancelled

1.2%

avg delay 15 min

Best time to leave

Before 9 AM

80% on time vs 69% after 9 PM

Most reliable airline

Delta

83% chance on time

Check SFO to SEA fares

Fares open on our travel partner (Aviasales). Pick the flight number you chose here.

Most reliable nonstop flights

Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.

  1. #1 · Delta 2721

    5:55 AM → 8:16 AM2h 20m nonstop

    Local times, typical schedule. Last flown 2026-05-31.

    95%

    chance on time

    On time (history)
    97%
    Cancelled
    0.9%
    Avg arrival delay
    3 min
    • Arrived on time 97% of the time (346 flights, Jun 2025 to May 2026).
    • Leaves in this route's most on-time window (Before 9 AM: 80% on time; After 9 PM: 69%).
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).

    Strong track record · 346 flights

    Find Delta 2721 fares Opens this date on Aviasales

  2. #2 · Alaska 416

    6:00 AM → 8:17 AM2h 17m nonstop

    Local times, typical schedule. Last flown 2026-05-31.

    88%

    chance on time

    On time (history)
    93%
    Cancelled
    1.1%
    Avg arrival delay
    4 min
    • Arrived on time 93% of the time (94 flights, Jun 2025 to May 2026).
    • Leaves in this route's most on-time window (Before 9 AM: 80% on time; After 9 PM: 69%).
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).

    Moderate track record · 94 flights

    Find Alaska 416 fares Opens this date on Aviasales

  3. #3 · United 1597

    12:25 PM → 2:46 PM2h 21m nonstop

    Local times, typical schedule. Last flown 2026-04-29.

    84%

    chance on time

    On time (history)
    91%
    Cancelled
    0.0%
    Avg arrival delay
    4 min
    • Arrived on time 91% of the time (32 flights, Jun 2025 to May 2026).
    • Never cancelled in 32 scheduled flights.
    • Departs inside SFO's trouble window: 61% of its 333 ground stops and delay programs started between 7 AM and 1 PM.
    • Short track record (32 flights), so its score leans on the airline's record at this hour.

    Limited track record · 32 flights

    Find United 1597 fares Opens this date on Aviasales

  4. #4 · Alaska 68

    6:30 AM → 8:47 AM2h 17m nonstop

    Local times, typical schedule. Last flown 2026-04-20.

    81%

    chance on time

    On time (history)
    83%
    Cancelled
    1.1%
    Avg arrival delay
    14 min
    • Arrived on time 83% of the time (90 flights, Jun 2025 to May 2026).
    • Leaves in this route's most on-time window (Before 9 AM: 80% on time; After 9 PM: 69%).
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).

    Moderate track record · 90 flights

    Find Alaska 68 fares Opens this date on Aviasales

  5. #5 · United 2744

    12:16 PM → 2:36 PM2h 20m nonstop

    Local times, typical schedule. Last flown 2026-05-30.

    80%

    chance on time

    On time (history)
    77%
    Cancelled
    3.2%
    Avg arrival delay
    15 min
    • Arrived on time 77% of the time (30 flights, Jun 2025 to May 2026).
    • Cancelled 3.2% of the time (1 of 31).
    • Departs inside SFO's trouble window: 61% of its 333 ground stops and delay programs started between 7 AM and 1 PM.
    • 60% of its delay minutes came from the plane arriving late from an earlier flight.

    Limited track record · 30 flights

    Find United 2744 fares Opens this date on Aviasales

  6. #6 · United 1577

    6:28 PM → 8:53 PM2h 25m nonstop

    Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as United 1763; its record covers all of them.

    80%

    chance on time

    On time (history)
    79%
    Cancelled
    0.0%
    Avg arrival delay
    15 min
    • Arrived on time 79% of the time (94 flights, Jun 2025 to May 2026).
    • Never cancelled in 94 scheduled flights.
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).
    • Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.

    Moderate track record · 94 flights

    Find United 1577 fares Opens this date on Aviasales

  7. #7 · United 1434

    6:40 PM → 8:58 PM2h 18m nonstop

    Local times, typical schedule. Last flown 2026-03-28.

    79%

    chance on time

    On time (history)
    92%
    Cancelled
    0.0%
    Avg arrival delay
    5 min
    • Arrived on time 92% of the time (24 flights, Jun 2025 to May 2026).
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).
    • Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
    • Short track record (24 flights), so its score leans on the airline's record at this hour.

    Limited track record · 24 flights

    Find United 1434 fares Opens this date on Aviasales

  8. #8 · United 2279

    4:12 PM → 6:32 PM2h 22m nonstop

    Local times, typical schedule. Last flown 2026-05-31.

    79%

    chance on time

    On time (history)
    81%
    Cancelled
    0.0%
    Avg arrival delay
    16 min
    • Arrived on time 81% of the time (205 flights, Jun 2025 to May 2026).
    • Never cancelled in 205 scheduled flights.
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).
    • Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.

    Strong track record · 205 flights

    Find United 2279 fares Opens this date on Aviasales

  9. #9 · United 694

    10:05 AM → 12:25 PM2h 20m nonstop

    Local times, typical schedule. Last flown 2026-05-20.

    76%

    chance on time

    On time (history)
    67%
    Cancelled
    0.0%
    Avg arrival delay
    21 min
    • Arrived on time 67% of the time (18 flights, Jun 2025 to May 2026).
    • Departs inside SFO's trouble window: 61% of its 333 ground stops and delay programs started between 7 AM and 1 PM.
    • Short track record (18 flights), so its score leans on the airline's record at this hour.

    Limited track record · 18 flights

    Find United 694 fares Opens this date on Aviasales

  10. #10 · Delta 1412

    2:55 PM → 5:09 PM2h 19m nonstop

    Local times, typical schedule. Last flown 2026-05-31.

    76%

    chance on time

    On time (history)
    77%
    Cancelled
    2.1%
    Avg arrival delay
    20 min
    • Arrived on time 77% of the time (331 flights, Jun 2025 to May 2026).
    • Departs outside SFO's trouble window (7 AM to 1 PM, when 61% of its 333 ground stops and delay programs started).
    • Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
    • 61% of its delay minutes came from the plane arriving late from an earlier flight.

    Strong track record · 331 flights

    Find Delta 1412 fares Opens this date on Aviasales

Airlines on this route

Season-adjusted chance of operating and arriving on time.

  • Delta Air Lines83%

    894 flights · 85% on time as flown · 1.8% cancel

  • United Airlines77%

    2,014 flights · 78% on time as flown · 0.4% cancel

  • SkyWest Airlines (sold as United Express, Delta Connection, American Eagle or Alaska)74%

    1,110 flights · 75% on time as flown · 1.1% cancel

  • Alaska Airlines67%

    2,747 flights · 68% on time as flown · 1.6% cancel

On time by departure time

All airlines, scheduled local departure, Jun 2025 to May 2026.

  • Before 9 AM80%

    1,185 flights · avg delay 10 min

  • 9 AM to noon76%

    1,322 flights · avg delay 14 min

  • Noon to 3 PM75%

    1,234 flights · avg delay 16 min

  • 3 to 6 PM73%

    1,038 flights · avg delay 17 min

  • 6 to 9 PM70%

    1,521 flights · avg delay 18 min

  • After 9 PM69%

    468 flights · avg delay 17 min

Best day: Tuesday (82%). Worst: Friday (74%).

Smarter routing

Nearby airports that run more on time

  • SJC → SEA 83% chance on time

    Norman Y. Mineta San Jose International Airport to Seattle–Tacoma International Airport · 4,379 flights a year · 30 mi from your airports · yours: 73%

    Rank flightsFares

  • OAK → SEA 77% chance on time

    Oakland San Francisco Bay Airport to Seattle–Tacoma International Airport · 1,934 flights a year · 11 mi from your airports · yours: 73%

    Rank flightsFares

On time by month

All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.

J
84
F
81
M
78
A
75
M
68
J
70
J
73
A
75
S
79
O
81
N
83
D
77

What delays this route

  • Late-arriving aircraft45%
  • Airline (crew, maintenance, boarding)27%
  • Air traffic control and airport volume26%
  • Severe weather3%

Share of delay minutes by the cause airlines report to the US DOT.

Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure

SFO to SEA questions

What time of day is best to fly SFO to SEA?
Before 9 AM: 80% of flights arrived on time, against 69% for departures after 9 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
Which airline is most on time from SFO to SEA?
Delta, with a season-adjusted 83% chance of operating and arriving on time over 894 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
What is the worst month for delays on SFO to SEA?
May (68% on time); the best was January (84%), averaged over Jun 2023 to May 2026.
Is this a prediction for my flight?
No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.

More routes from SFO

Live status: FAA delays and ground stops