OnTimeStats

Airport on-time performance

Seattle

Data through May 2026Source: US DOT · BTS
On-time rate78%flights departing here that arrived on time
p90 delay35 min1 in 10 departures is worse (tail risk)
Cancelled1.0%of scheduled departures
Left the gate on time79%departures that pushed back within 15 min of schedule (DepDel15)

based on 165,477 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

As a connection hub

Arriving here (inbound performance)

These figures reflect inbound flights arriving at this airport — relevant for connections and layovers.

78%arrived on time here
(within 15 min, inbound flights)
  • On time78%
  • 15–59 min late15%
  • 1–2 hr late3%
  • 2 hr+ late2%
  • Cancelled or diverted1%

Arrival outcomes for inbound flights. Last segment = cancelled or diverted.

Bad day: 1 in 10 flights arrives more than 35 min late.

By airline

Carriers departing here (last 12 months)

Delay = arrival delay (ArrDel15-based)

  • SkyWest Airlines
    On-time85%
    Medianon time
    p9020 min
    Cancel0.7%
    Flights28,259
  • Envoy Air
    On-time84%
    Medianon time
    p9020 min
    Cancel0.0%
    Flights631
  • Delta Air Lines
    On-time80%
    Medianon time
    p9030 min
    Cancel1.1%
    Flights31,223
  • United Airlines
    On-time80%
    Medianon time
    p9040 min
    Cancel0.8%
    Flights8,751
  • American Airlines
    On-time76%
    Medianon time
    p9040 min
    Cancel2.2%
    Flights6,311
  • Alaska Airlines
    On-time75%
    Medianon time
    p9035 min
    Cancel1.1%
    Flights74,995
  • Frontier Airlines
    On-time73%
    Medianon time
    p9055 min
    Cancel2.1%
    Flights482
  • Southwest Airlines
    On-time71%
    Medianon time
    p9045 min
    Cancel0.4%
    Flights7,862
  • Spirit Airlines
    On-time68%
    Medianon time
    p9035 min
    Cancel1.4%
    Flights72
  • Hawaiian Airlines
    On-time59%
    Median5 min
    p9070 min
    Cancel1.1%
    Flights1,211
  • JetBlue Airways
    On-time57%
    Median5 min
    p90100 min
    Cancel1.2%
    Flights327

Over time

On-time trend

By season

On-time rate by month

When it gets busy

Busiest times at SEA

Historically, departures at SEA peak 5–10 a.m. — 28% of scheduled flights leave in that block.

  • Midnight–5 a.m.1%
  • 5–10 a.m.28%
  • 10 a.m.–2 p.m.25%
  • 2–5 p.m.13%
  • 5–8 p.m.17%
  • 8 p.m.–midnight16%

Share of 493,270 scheduled departures by planned departure time, 2023-06 .. 2026-05. Historical averages from BTS data — not live airport status.

When flights don't go

Why flights were cancelled

  • Airline50%
  • Weather39%
  • Air traffic (NAS)11%
  • Security0%

Most cancellations here are attributed to Airline. Shares are among 1,663 cancellations with a reported cause (BTS reports causes from June 2003).

Where flights go

Busiest routes

SEA → LAX→SEA → SFO→SEA → ANC→SEA → DEN→SEA → PHX→SEA → LAS→SEA → ORD→SEA → GEG→SEA → DFW→SEA → SJC→

Side by side

Compare this airport

Compare with Hartsfield Jackson Atlanta International Airporthead-to-head on-time→Compare with Chicago O'Hare International Airporthead-to-head on-time→Compare with Dallas Fort Worth International Airporthead-to-head on-time→Compare with Denver International Airporthead-to-head on-time→

Will you make a connection at SEA? →

Keep exploring

Related guides

When to arrive at the airportguide→Worst airports for delaysguide→

Methodology

A flight is on time when it arrives within 15 minutes of schedule — the US DOT / BTS standard. Median and p90(the “1-in-10 bad day”) are read from the full arrival-delay distribution, never averaged across periods.

Figures cover a carrier’s own BTS-coded flights. Cells below ~200 flights are flagged as limited data. All numbers are pre-computed from public BTS On-Time Performance data.