How long is the flight from Seattle to London?

Non-stop flights on SEA → LHR are typically around 9.5 hours. Connecting itineraries add 3–8 hours depending on the hub and layover.

Which airlines fly from Seattle to London?

The main carriers on this route are British Airways, Virgin Atlantic, American. Codeshare and one-stop options add several more — the filter panel above shows every airline in the current fare set.

When is the cheapest time to fly from Seattle to London?

Historically the lowest fares land in January, February, November. Summer (mid-June through mid-August) and the Christmas / New Year window are always peak. Mid-week departures (Tuesday–Thursday) typically beat weekend prices by 10–20%.

How far ahead should I book Seattle to London?

Six to ten weeks ahead is the sweet spot for this route. Inside three weeks, fares tend to spike as airlines sell to last-minute business travellers. Award availability often opens 10–11 months out if you're booking on miles.

Can I book directly on destination.com?

The Book button on each fare opens the airline or OTA (Trip.com, Kiwi, Expedia, Booking, Priceline, etc.) that's actually selling that ticket. You complete payment there at the same price you saw here — we never add a markup.

SEA → LHR

Seattle to London flights.

Live cached fares on Seattle (SEA) → London (LHR), refreshed every 30 minutes. Non-stop and connecting itineraries side by side — compare airlines, times and stops, then book in one click.

Flying time
~9.5h non-stop
Airlines
British Airways, Virgin Atlantic, American
Cheapest months
January, February, November

Flex dates · cheapest nearby

Loading prices…

No cached fares for exactly 2026-06-08 → 2026-06-15. Showing recent fares on SEA → LHR — pick a different date in the calendar above or run a live search.

Seattle → London · 3 fares

Cached from Travelpayouts · filter & sort below

Showing 2 of 3 results

Cheapest
Icelandair · FI 680
OutboundSEA → LHRMon, Aug 17 · 10:40 PM· 10h 50m· 1 stop
ReturnLHR ← SEAFri, Sep 25 · 12:05 PM· 11h 5m· 1 stop
$610
total round-trip
Book →
Turkish Airlines · TK 204
OutboundSEA → LHRSun, Jun 14 · 2:10 AM· 15h 55m· 1 stop
ReturnLHR ← SEASun, Jun 21 · 9:40 PM· 16h 10m· 1 stop
$930
total round-trip
Book →

Try a nearby airport

Thin routes often have more options from a neighbouring airport.

Portland (PDX) → London (LHR)

nearby origin

Seattle (SEA) → London (LGW)

nearby destination

Seattle (SEA) → London (STN)

nearby destination

About Seattle → London

BA + Virgin daily non-stops. SEA's tech-corridor demand keeps premium cabins tight but economy shoulder fares are PNW-friendly.

Typical non-stop flying time is around 9.5 hours. Major carriers on this route include British Airways, Virgin Atlantic, American. Fares are usually cheapest in January, February, November — book 6–10 weeks ahead and avoid school-holiday peaks (late June–August, Christmas–New Year) for the best pricing.

Month-by-month price guide: Seattle to London

Live cheapest round-trip fare cached on SEA → LHR for each of the next 12 months. Tap any month and run a live search to confirm.

Apr
No data
May
No data
Jun
Peak
from $930
Jul
No data
Aug
Low
from $610
Sep
No data
Oct
No data
Nov
No data
Dec
No data
Jan
No data
Feb
No data
Mar
No data

Cheapest next 12 months: August from $610 round-trip. Run a live search →

Booking window tip

Long-haul fares are most predictable when booked 10-16 weeks ahead. Inside six weeks expect sharp increases, especially in premium cabins. If you're paying with miles, search 330+ days ahead when award inventory first loads.

Questions, answered

How long is the flight from Seattle to London?
Non-stop flights on SEA → LHR are typically around 9.5 hours. Connecting itineraries add 3–8 hours depending on the hub and layover.
Which airlines fly from Seattle to London?
The main carriers on this route are British Airways, Virgin Atlantic, American. Codeshare and one-stop options add several more — the filter panel above shows every airline in the current fare set.
When is the cheapest time to fly from Seattle to London?
Historically the lowest fares land in January, February, November. Summer (mid-June through mid-August) and the Christmas / New Year window are always peak. Mid-week departures (Tuesday–Thursday) typically beat weekend prices by 10–20%.
How far ahead should I book Seattle to London?
Six to ten weeks ahead is the sweet spot for this route. Inside three weeks, fares tend to spike as airlines sell to last-minute business travellers. Award availability often opens 10–11 months out if you're booking on miles.
Can I book directly on destination.com?
The Book button on each fare opens the airline or OTA (Trip.com, Kiwi, Expedia, Booking, Priceline, etc.) that's actually selling that ticket. You complete payment there at the same price you saw here — we never add a markup.

Other ways to reach London

If your plans are flexible on the origin, these alternate departure airports also serve London on the routes we track.

Other popular routes

Keep planning

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