International route
Cheap flights from Seattle to London
Seattle-Tacoma International Airport (SEA) to London Heathrow Airport (LHR). 4,786 miles, 9h 15m nonstop.
SEA to LHR at a glance
Computed from airline schedules and the fares we track for this route. Refreshed several times a day.
- Distance
- 4,786 milesgreat-circle
- Typical flight time
- 9h 15mnonstop, gate to gate
- Nonstop airlines
- DLUAASBA5 airlinesDelta, United, Alaska
- Nonstop flights per day
- 9all airlines combined
- Cheapest month
- January 2027over the next six months
- Best day to fly
- Tuesday19% less than Friday
- Time difference
- 8h aheadLondon vs Seattle
Seattle to London
Round trips from $366
Per traveler, taxes and fees included. Lowest fare we found departs Wed, Jan 6.
Cheapest month: January 2027
See fares on these datesLock any fare free — pay only when you accept your last-minute deal
Or ask an agent on WhatsAppSeattle to London fares by month
Lowest round-trip economy fare per traveler in each of the next six months, taxes and fees included. Select a month to search that date.
Airlines flying Seattle to London
5 airlines fly nonstop with 9 departures a day combined, plus 17 more with one stop.
- ASAlaska AirlinesoneworldNonstop · 2 flights a day · first checked bag from $35
- BABritish AirwaysoneworldNonstop · 2 flights a day · first checked bag from $75
- DLDelta Air LinesSkyTeamNonstop · 2 flights a day · first checked bag from $35
- VSVirgin AtlanticSkyTeamNonstop · 2 flights a day · first checked bag from $75
- UAUnited AirlinesStar AllianceNonstop · 1 flight a day · first checked bag from $40
- EIAer LingusConnecting via DUB, SNN · first checked bag from $70
- ACAir CanadaStar AllianceConnecting via YVR, YUL, YYC · first checked bag from $35
- AFAir FranceSkyTeamConnecting via ORY · first checked bag from $75
- AAAmerican AirlinesoneworldConnecting via DFW, CLT, ORD, MIA, PHX, PHL, DCA, JFK · first checked bag from $40
- AYFinnaironeworldConnecting via HEL · first checked bag from $70
- AZITA AirwaysConnecting via FCO · first checked bag from $70
- B6JetBlueConnecting via JFK, BOS, MCO, LAX · first checked bag from $40
- KLKLM Royal Dutch AirlinesSkyTeamConnecting via AMS · first checked bag from $75
- LHLufthansaStar AllianceConnecting via FRA, MUC · first checked bag from $75
- NONorse Atlantic AirwaysLow-costConnecting via OSL · first checked bag from $80
- SKSAS Scandinavian AirlinesSkyTeamConnecting via CPH, ARN, OSL · first checked bag from $70
- LXSWISSStar AllianceConnecting via ZRH, GVA · first checked bag from $75
- TPTAP Air PortugalStar AllianceConnecting via LIS, OPO · first checked bag from $70
- TKTurkish AirlinesStar AllianceConnecting via IST · first checked bag from $70
- VBVivaLow-costConnecting via MTY, CUN · first checked bag from $45
- Y4VolarisLow-costConnecting via TIJ, CUN · first checked bag from $45
- WSWestJetConnecting via YYZ · first checked bag from $35
Connecting options
Hubs where one airline can carry you on both legs, most choices first.
- New York (JFK)AAB62 airlines
- Cancun (CUN)VBY42 airlines
- Oslo (OSL)SKNO2 airlines
- Dallas (DFW)AA1 airline
- Charlotte (CLT)AA1 airline
Which airport should I use?
SeattleLondon has 3 airports. Fares can differ by $50 to $150 round trip between them, so check the alternatives before you book.
Tips for this route
- Delta, United, Alaska and British all fly SEA to LHR nonstop, so compare the total with bags before picking the lowest base fare: the difference between a basic and a standard economy ticket is often less than one checked bag each way.
- January 2027 is the cheapest month to fly over the next six months, with round trips from $366; September 2026 is the most expensive at $499 and up, a difference of $133 per traveler.
- Departing on a Tuesday averages 19% less than a Friday on this route. If your dates are flexible, shift the outbound by a day or two and check the calendar view before you book.
- Book 2 to 5 months ahead for the best fares; long-haul seats sell out earliest for summer and holiday travel.
- London is 8 hours ahead of Seattle. Expect to lose 8 hours on the clock heading east, so an overnight or late-afternoon departure tends to arrive at a more usable hour.
Destination guide
London: The most-flown transatlantic route, for good reason
London is the busiest international destination from the US, with nonstops from more than 30 American cities into Heathrow and Gatwick. The museums are free, the theater is world-class and the Tube reaches everything — including Heathrow.
Best time to visit: May–June and September are mild with long days; July–August is warm and busy. December has Christmas markets and lights. January–March is cold and gray but fares can drop below $500 round trip.
Flying the other way? London to SeattleFares, airlines and tips for LHR to SEA.Ready to compare live fares?
See every airline on SEA–LHR side by side with bags and seat rules spelled out.
Search Seattle to LondonSeattle to London: common questions
How long is the flight from Seattle to London?
A nonstop flight from Seattle (SEA) to London (LHR) takes about 9h 15m gate to gate, covering 4,786 miles. Connecting itineraries add the layover, typically 2 to 5 hours more in total.
Which airlines fly nonstop from SEA to LHR?
Delta Air Lines, United Airlines, Alaska Airlines, British Airways and Virgin Atlantic operate nonstop flights from Seattle (SEA) to London (LHR), with 9 nonstop departures a day between them. One-stop options connect through JFK, CUN and OSL.
What is the cheapest month to fly from Seattle to London?
Over the next six months, January 2027 has the lowest round-trip fares from Seattle (SEA) to London (LHR), starting at $366 per traveler including taxes and fees. Within any month, Tuesday departures average the lowest prices.
How far in advance should I book Seattle to London flights?
Book 2 to 5 months ahead for the best fares; long-haul seats sell out earliest for summer and holiday travel. Air1 Tickets includes free cancellation within 24 hours of booking on every fare, so you can lock in a good price and keep looking.
What is the time difference between Seattle and London?
London is 8 hours ahead of Seattle. SEA is on America/Los Angeles time and LHR on Europe/London time. Departure and arrival times in search results are always shown in local time at each airport.
Related routes
Other popular city pairs from the same departure city and to the same destination, with the lowest round-trip fares we found.