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Seattle-Tacoma International (SEA) departure delays

Name: Seattle-Tacoma International (SEA) departure delays
Creator: FlightLabs

Of 10,949 sampled departures, 64.0% left 15 minutes or more behind schedule. Average lateness was 31.3 minutes. Sample window: Nov 15, 2025 to Jul 28, 2026.

These are historical aggregates, not live status. A departure is late at 15 minutes past schedule.

When departures are on time

Best hour to depart: 23:00–23:59, 47.9% late.
Best day of week: Saturday, 55.5% late.

Airlines with the most late departures

Airline	Flights sampled	Late	Average lateness
Air Canada (AC)	62	93.6%	54.6 min
Empire Airlines (EM)	20	90.0%	48.8 min
Korean Air (KE)	25	88.0%	47.0 min
Southwest Airlines Co. (WN)	284	86.3%	47.8 min
British Airways (BA)	51	84.3%	26.3 min

Routes from SEA

SEA to PDX — 194 flights per week
SEA to PHX — 169 flights per week
SEA to GEG — 159 flights per week
SEA to ANC — 157 flights per week
SEA to LAX — 157 flights per week
SEA to YVR — 125 flights per week
SEA to SFO — 118 flights per week
SEA to DEN — 116 flights per week

The departures that are late right now

64.0% of this SEA sample left 15 minutes late or more. GET /flight_delays returns the ones that are late at this moment: airline, flight number, scheduled time, actual time and minutes of delay.

https://www.goflightlabs.com/flight_delays?access_key=YOUR_ACCESS_KEY&delay=15&type=departures&dep_iata=SEA

Example response

Field names match the live API. This flight only shows the shape. It is not a live result.

{ "success": true, "data": [ { "airline_iata": "AA", "flight_iata": "AA100", "flight_number": "100", "dep_iata": "SEA", "dep_time": "2024-03-15 08:00", "dep_actual": "2024-03-15 08:22", "dep_delayed": 22, "status": "active" } ] }

That URL still says YOUR_ACCESS_KEY. A 7-day trial replaces it with a real key and returns the SEA departures that are late right now, in the JSON above. After the trial, Starter is $24.99/mo.

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