SEA → LHRSeattle to London

live

Direct flights from Seattle (SEA) to London (LHR): 28 nonstop departures observed each week across 4 airlines. 78% of the last 9 operated flights arrived within 15 minutes of schedule. The median arrival is 21 minutes early. No cancellations were recorded across the 9 tracked flights. The nonstop covers 7,702 km, an estimated 10 hours 22 minutes in the air. Measured by Pro Flight Search from live flight boards at Seattle and London. Updated 10 October 2026 at 02:25 UTC.

SEA Seattle disrupted · +96
LHR London busy · +15
7,702 km · ~10h 22m est.
dep bank 13:30–21:5028x weekly
Runs mixed · 4 airlines · 28x weekly · nonstop
78% on time

of the last 9 operated SEA → LHR flights arrived within 15 minutes

Median arrival delay is −21 min. 0 of 9 tracked legs cancelled in the sample. Will a delayed flight be cancelled? →

Median arrival−21 minacross the last 9 operated legs
Flight time~10h 22mestimated from route distance
Weekly departures28x4 direct airlines on the leg

The week

scheduled departures · origin local time
06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Alaska AirlinesBritish AirwaysDelta Air LinesVirgin Atlantic Airways

Each mark is a scheduled departure at its origin-local time, observed operating in the last 7 days. Today is highlighted.

Who flies it

observed on the boards · 7 days
Alaska AirlinesAS

Flights AS100 21:40 daily

British AirwaysBA

Flights BA52 13:30 daily · BA48 20:20 daily

Delta Air LinesDL

Flights DL20 21:50 daily

Virgin Atlantic AirwaysVS

Flights VS106 17:30 daily

History

operated legs · board outcomes
10-09BA48dep +26 → arr+61
10-09BA52arrived+25
10-09DL20arrived−21
10-09VS106arrived−33
10-08AS100arrived−23
10-08BA48arrived+3
10-08BA52arrived+6
10-08DL20arrived−25
10-08VS106arrived−46

Actual board outcomes rather than schedules, paired departure and arrival per flight and day.

Full board history, day by day →

Airports right now

live boards
SEASeattle +96 min disrupted 🌤 overcast · ESE 7 kt Full SEA delay board →
LHRLondon +15 min busy 🌤 clear · WSW 8 kt Full LHR delay board →

Weather lens

Current conditions put the pressure at SEA: 32% odds of a 15+ minute delay and around +3 min expected when it bites, measured from this route's own weather-matched delay history. See live delays → · Weather risk by airport →

How the Seattle to London route actually runs

Pro Flight Search records official board updates for nonstop SEA to LHR flights through the day: schedules, estimates, gate pushes and actual departures. The verdict above comes from operated flights, so it reflects what this route does rather than what the timetable promises.

Planning around a delay? Live airport delays · Weather delay risk map · Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure

Cite this data

Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.

Suggested citation

Pro Flight Search — Seattle (SEA) to London (LHR) route reliability, measured from operated flights on official airport boards.

Canonical URL
https://proflightsearch.com/search-flights/SEA-LHR
How we measure this →

SEA to LHR questions

Is SEA–LHR running on time right now?

Significant delay risk. The departure side at SEA is the weaker end, route health score 40/100. The airports section above carries the live status and delay window at both ends.

Morning or evening flight on SEA–LHR?

Operators schedule evening departures around 17:30 from SEA. Earlier flights typically land before destination-airport delays accumulate later in the day; check the LHR delay card to confirm conditions when you'd arrive.

How long is the flight from SEA to LHR?

Great-circle distance is 7,702 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 574–690 min gate-to-gate on this route.

How often does SEA–LHR fly?

4 carriers operate this route, around 35 flights a week between them. Compare carrier days and times in the airline list above.