💰 When is the cheapest time to fly from Seattle to London?
This month: May dips back to a floor — about 25% under the average — in the gap before summer demand.
Seattle to London economy averages about $810 round trip, ranging roughly $574 to $1,130 across the year.
The cycle has two floors: January after the holiday demand collapse, and May in the spring window before summer pricing arrives. Each runs roughly 30% below the July peak.
The ceilings are July (school holidays and peak European summer) and the December holiday return rush. Shoulder months like March, September and October sit near the average and reward a fare alert.
With four nonstop carriers competing on one route, SEA fares stay flexible — a sub-$650 economy round trip in the floor months is realistic when one carrier runs a sale.
✈️ Which airlines fly from Seattle to London?
Four carriers fly Seattle to London Heathrow nonstop, a depth no other US West Coast city outside California matches.
Alaska, Delta and Virgin Atlantic all use Terminal 3; British Airways uses Terminal 5. Delta and Virgin share a SkyTeam joint venture, while Alaska and BA earn oneworld miles — so Seattle flyers pick the alliance, then the metal.
The SkyMiles anchor and the value pick from a Delta hub.
SEA is a Delta hub, so the airline runs the most frequent SEA-LHR departures and the widest fare spread — it usually owns the floor months. Expect the A330-900neo or 767-400ER with Delta One lie-flat business up front.
Delta and Virgin Atlantic are one joint venture, so a SkyMiles award can ride either carrier's metal from Terminal 3. The catch is Basic Economy: it includes no checked bag, so add the bag before you compare fares.
Best for: SkyMiles loyalists, value economy from the SEA hub, travelers wanting frequent departure choice
The hometown carrier with a brand-new cabin and the best local miles.
Alaska launched this route on May 21, 2026 — its first long-haul international flight from Seattle. The 787-9 debuts Alaska's first lie-flat business suites: 34 seats with sliding doors and direct aisle access, plus 266 economy seats (72 Premium with extra legroom).
It earns Mileage Plan and connects through oneworld at Terminal 3. Flight AS100 departs SEA around 9:40pm. Skip the Saver fare if you check a bag — it includes none.
Best for: Mileage Plan members, PNW locals backing the hometown carrier, business flyers wanting the newest suite
The full oneworld experience into Terminal 5 with the deepest onward Europe.
British Airways flies 777 and 787 widebodies into its home base at Terminal 5, where the onward European network is unmatched — ideal if London is a gateway, not the destination. The Club Suite business cabin has doors and direct aisle access.
BA earns Avios and shares oneworld with Alaska, so the two can sit on one award. Avoid BA's Basic economy if you check a bag, and budget for seat-selection fees that some competitors waive.
Best for: oneworld and Avios earners, travelers connecting onward in Europe, Club Suite seekers
The most personality in the cabin, and a SkyMiles twin of Delta.
Virgin Atlantic flies the A350-1000 or 787-9 with its signature Upper Class suite and the onboard Loft social space — the most distinctive cabin on the route. It uses Terminal 3 alongside Delta.
Because Virgin and Delta are one joint venture, your SkyMiles earn and burn the same on either, so chase whichever has award space. Skip Economy Light if you check a bag, since it strips the included allowance.
Best for: premium leisure couples, cabin-experience seekers, SkyMiles flyers chasing award space
Mubboo verdict: Delta and Virgin Atlantic anchor the route on the SkyMiles joint venture. Alaska's new 787-9 suites win on hometown miles. Skip basic economy if you check a bag.
Prices shown are approximate averages based on recent searches (April 2026). Actual fares vary by date, class, and availability.
🎯 Ready to compare flights?
We compare prices from airlines and travel platforms so you can find the best deal.
Compare all flights →📅 When should you book Seattle to London flights?
Book 6 to 10 weeks ahead for normal travel and 3 to 4 months for July and December peaks.
We tracked fares across major booking platforms: the non-peak sweet spot lands about two months out, and Tuesday or Wednesday departures usually beat weekends.
Summer and holiday seats climb fast — July economy can run double a January fare. Award space on Alaska Mileage Plan and Delta SkyMiles opens around 331 days out, so points travelers should set alerts when the schedule loads.
With four nonstop carriers competing, SEA fares stay flexible — a sub-$650 economy round trip in the floor months is realistic when one runs a sale.
Chelsea Flower Show late month, long 60°F evenings. The underrated value window before summer pricing lands.
If you're a family flying in summer, book by March — peak season fills up fast.
Budget travelers: shoulder season (Sep–Oct, Apr–May) offers the best balance of price and weather.
💡 This May: A sleeper-cheap month; book mid-May after the bank holidays for the spring sweet spot.
🏙️ Why visit London?
London rewards the short Atlantic hop more than its nine hours suggest.
For Seattle flyers used to long Pacific hauls, London is the rare world capital reachable in under ten hours nonstop — and it unfolds in distinct villages, not one center.
The City packs a thousand years of history between glass towers; cross to the South Bank for Tate Modern, the London Eye and a Thames-side walk.
West in Notting Hill, pastel townhouses and Portobello Road give a residential calm. Soho and Covent Garden form the West End core, while Shoreditch and Camden trade polish for food markets and lower hotel prices.
The Underground and Elizabeth Line stitch it together. Base central, then let the city's quieter side reveal itself a few stops out.
What makes London worth the flight:
Plan 4 to 6 nights for a first trip; London scales with your stamina.
In 8 hours, walk Westminster and Big Ben, ride the London Eye, cross to the South Bank for Tate Modern, and finish with a West End show in Soho.
In 48 hours, add the Tower of London and Tower Bridge in the morning, the British Museum after lunch, and an evening in Shoreditch for food markets and street art.
In a week, slow down: a morning in Borough Market, a Notting Hill stroll through Portobello Road, a day trip by train to Oxford or the Cotswolds, and an afternoon in Greenwich for the Observatory and river views. London never runs out before you do.
Best neighborhoods to explore:
The all-rounder base: West End theaters, the National Gallery, Trafalgar Square and the piazza's street performers, all on foot. Best for a short first trip when transit time matters most.
A riverside walk linking the London Eye, Tate Modern, the Shard and Borough Market, with footbridges straight into the City and West End. The single best stretch for big-attraction density.
The creative east: street art, vintage shops, the Sunday markets at Brick Lane and Columbia Road, and London's strongest food scene — at noticeably lower hotel prices than the West End.
Pastel townhouses, the Portobello Road antiques market, and quiet garden squares. A residential, bohemian calm a short Tube ride from the center — famous from the film, lovely in person.
London's financial core, where Roman walls meet the Gherkin. Quieter on weekends, well-connected, and the natural base for Seattle's tech and finance travelers with London meetings.
Canal-side markets, live-music history, and a high-energy street scene a few stops north of the center. Affordable, lively, and a quick hop to King's Cross for onward trains.
Don't miss:
Tower of London (the City)
A 1,000-year-old fortress guarding the Crown Jewels, with Yeoman Warder tours and the ravens. Arrive at opening to beat the crowds to the jewels and the White Tower armory.
Browse Tower of London (the City) tours →British Museum (Bloomsbury)
From the Rosetta Stone to the Parthenon sculptures, one of the world's great free museums. Go early or late; the Great Court is calmest near closing. Entry is free.
Browse British Museum (Bloomsbury) tours →Tower Bridge & Borough Market (Southwark)
The Victorian bascule bridge and its glass walkway, paired with the food stalls of Borough Market just upriver. Best as a late-morning combo — history then lunch.
Browse Tower Bridge & Borough Market (Southwark) tours →Westminster & Big Ben (central)
The Houses of Parliament, Westminster Abbey and the restored Elizabeth Tower clock. Walk the river at dusk when Big Ben lights up over Westminster Bridge.
Browse Westminster & Big Ben (central) tours →Tate Modern & the South Bank (Bankside)
A former power station turned free modern-art museum, with a top-floor city view and a riverside walk past the Globe Theatre. Free entry to the collection.
Browse Tate Modern & the South Bank (Bankside) tours →The London Eye (South Bank)
A 443-foot observation wheel with 30-minute rotations over the Thames and Westminster. Book a timed slot; sunset capsules are the photographer's window.
Browse The London Eye (South Bank) tours →Buckingham Palace & St James's Park (central)
The royal residence and the Changing of the Guard, framed by London's prettiest royal park. Check the guard schedule before you go; it does not run daily.
Browse Buckingham Palace & St James's Park (central) tours →M's take:
Base in Covent Garden or the South Bank for your first trip, and give east London a full day.
First-timers should anchor central near the Underground for fast access to everything, then spend one slow day in Shoreditch and Borough Market for the city's modern, market-driven side.
Skip a far-out budget hotel to save £30 — the lost transit time after an 8-hour jet-lag shift costs more than it saves. Don't over-schedule your arrival day.
🎟️ Top activities in London
Ranked by traveler ratings and recent booking volume.
British Museum & National Gallery of London Semi-Private 8ppl Max
$207Walking Tour around Spitalfields in the East End of London
$88.65Source: Viator · Prices in USD · Affiliate links — Mubboo may earn a commission.
🧳 What do you need to know before flying to London?
🛂 Do Americans need a visa for London?
UK ETA required · £20 · since Feb 25 2026 · US passport.
US passport holders no longer enter the UK freely. As of February 25, 2026, a UK Electronic Travel Authorisation (ETA) is mandatory for tourism, family visits, business meetings, or short study of 6 months or less, per the US State Department and GOV.UK.
The ETA is an electronic permission, not a visa. It costs £20, covers multiple visits of up to 6 months each over two years (or until your passport expires), and you apply on the official gov.uk service or app — most decisions arrive within minutes.
Your passport must stay valid for the length of your stay and hold at least one blank page. The UK carries a State Department Level 2 advisory. Always confirm current rules at travel.state.gov before travel.
🕐 What's the time difference?
London is 8 hours ahead of Seattle year-round.
London runs on GMT in winter and BST (UTC+1) in summer; Seattle shifts between PST (UTC-8) and PDT (UTC-7). Both observe daylight saving, so the gap holds steady at 8 hours most of the year.
An evening SEA departure around 9pm lands you in London mid-afternoon the next calendar day — the gentler way to cross, since you sleep onboard and arrive in daylight.
The eastbound direction is the harder jet lag for Pacific Northwest travelers: you lose a night and a full day. Plan a low-key first London evening rather than a packed itinerary, and chase morning sunlight to reset.
🚇 How do you get from the airport to the city?
Heathrow (LHR) sits about 15 miles west of central London. Fares are as of 2026 — verify with Transport for London:
| Option | Time | Cost | Best for |
|---|---|---|---|
| Elizabeth Line ✅ | 28–30 min to Paddington | about £15.50 (~$20) | Most travelers — modern, direct to central |
| Heathrow Express | 15 min to Paddington | about £25 (~$32); £10 if booked early | Speed over savings, Paddington-bound |
| Piccadilly Line (Tube) | 40–60 min | flat £5.90 (~$7.50) from Zone 1 | Budget travelers, light luggage |
| Black cab / rideshare | 45–75 min by traffic | about £60–80 (~$76–$102) | Late arrivals, groups, heavy bags |
Editor's pick: Ride the Elizabeth Line — it connects directly across central London for a third of a cab fare.
💷 What about money and tipping?
The UK uses the pound (GBP) and runs almost entirely on contactless.
Carry a no-foreign-transaction-fee card — the Chase Sapphire Preferred, Capital One Venture, or Amex Platinum all waive the 3% fee standard cards charge.
London is overwhelmingly contactless: tap your phone or card on buses, the Tube, and shops, and the daily fare cap applies automatically — no need to buy an Oyster card for a short trip. Add your card to Apple Pay or Google Pay before you fly.
Withdraw a little cash only for markets or smaller pubs. Tipping is modest: a service charge is often added in restaurants; round up for cabs. Exchange rates move weekly, so check current rates rather than budgeting on a fixed figure.
London currency snapshot
1 USD = 0.75 GBP
1 GBP = $1.340 USD
British Pound
Cash
ATMs offer the best rate. Avoid airport currency desks.
Tipping
ATMs everywhere. Contactless cards work on London transit. Tip 10-15% at sit-down restaurants.
Cards
Visa and Mastercard widely accepted. Tell your bank before you go.
Source: open.er-api.com · Updated May 20, 2026 · Rates fluctuate — check before booking.
📱 Will your phone work?
T-Mobile roams free in the UK; an eSIM is faster for heavy data.
T-Mobile Magenta includes free UK roaming at throttled speeds — fine for maps and chat, slow for video. AT&T and Verizon charge roughly $10 to $12 per day on their travel passes.
A travel eSIM is the better value for data-heavy trips: Saily, Airalo, and Ubigi sell UK or Europe data from about $5 for a week, activated before you land.
Free public Wi-Fi is widespread at Heathrow, on the Underground platforms, and in cafes and pubs, but coverage drops between stations — keep an eSIM as your primary connection if you rely on navigation or rideshare apps on the move.
☁️ London climate overview
Best: Apr, May, Jun, Jul, Aug, SepHistorical highs, lows, and rainfall by month. Plan packing and outdoor time around the extremes.
Jan
44°/35°F
3.3″ rain
Feb
46°/38°F
1.9″ rain
Mar
55°/40°F
0.5″ rain
Apr
63°/46°F
0.9″ rain
May
68°/51°F
1.1″ rain
Jun
76°/58°F
1.6″ rain
Jul
76°/61°F
3.0″ rain
Aug
74°/59°F
1.3″ rain
Sep
66°/53°F
2.4″ rain
Oct
59°/50°F
2.4″ rain
Nov
53°/44°F
3.0″ rain
Dec
49°/42°F
2.7″ rain
Source: Open-Meteo Archive API · 2025 historical data · Updated May 2026
✈️ Ready to book? Compare Seattle to London flights
Search flights →🛫 Flying from Seattle — airport tips
SEA South Satellite — Alaska international gates (Alaska)
- Alaska's flagship Seattle lounge near the main terminal serves Mileage Plan elites and oneworld business passengers before the underground ride to the South Satellite
- Flight AS100 to Heathrow departs around 9:40pm — check in opens about 3 hours prior and the international security line peaks early evening
- Saver fares include no checked bag; the Main fare adds one 23 kg bag, so price the bag in before comparing with Delta
SEA South Satellite — Delta international gates (Delta)
- SEA is a Delta hub, so SkyClub access and frequent SEA-LHR departures make Delta the flexible default for last-minute changes
- Delta and Virgin Atlantic share the SkyTeam joint venture — a SkyMiles award can ride either carrier's metal into Heathrow Terminal 3
- Basic Economy includes no checked bag and boards last; upgrade to Main Cabin if you check a bag or want a seat assignment
London Heathrow Terminal 3 — Alaska, Delta, Virgin Atlantic (Multiple (T3))
- Three of the four SEA carriers land at Terminal 3, so arrivals and the Elizabeth Line platform are a short, shared walk
- Virgin Atlantic's Clubhouse and Delta's SkyTeam lounges sit in T3 for eligible business and elite passengers on the return
- The Elizabeth Line and Heathrow Express both serve T3 directly — follow signs to the central station between terminals
London Heathrow Terminal 5 — British Airways (British Airways)
- BA's home terminal handles the deepest onward European network — ideal if London is a connection rather than the destination
- T5 is large; allow extra time for security on the return, which swings widely by time of day
- The Elizabeth Line does not stop at T5 directly — take the free inter-terminal transfer to the central station or ride the Heathrow Express
🚐 Skip the hassle? Book a private airport transfer
Fixed price, meet & greet at arrivals, door-to-door service
💡 Insider tips: Seattle to London
Pick your alliance first — SkyTeam (Delta/Virgin) or oneworld (Alaska/BA) — then the metalMubboo original data
Seattle is unusual: all four SEA-LHR carriers split cleanly into two alliances, so your miles decide the airline.
Delta and Virgin Atlantic are one SkyTeam joint venture from Terminal 3 — a single SkyMiles award rides either. Alaska and British Airways both earn oneworld miles, with Alaska at T3 and BA at Terminal 5.
That means you can chase award space across two carriers per alliance on one short route. Decide where your points live, then book whichever of the pair has the seat.
Take the evening SEA departure for an onboard sleep and a daylight London arrivalMubboo original data
Every SEA-LHR nonstop leaves in the evening for a reason.
Alaska's AS100 departs around 9:40pm; the others cluster nearby. With an 8-hour time gap and a 9h 25m crossing, a 9pm departure lands you in London mid-afternoon the next day.
That lets you sleep across the Atlantic and arrive in daylight, which is the only humane way to handle the brutal eastbound jet lag from the Pacific Northwest. Avoid scheduling anything demanding on arrival evening — your body clock thinks it's 7am.
Alaska's new 787-9 suites are the freshest cabin on the route
The newest hardware on SEA-LHR belongs to the hometown carrier.
Alaska's 787-9, flying since May 2026, carries the airline's first lie-flat business suites: 34 seats with sliding doors and direct aisle access. Economy holds 266 seats, with 72 Premium rows adding about 3 inches of legroom.
For a daytime-sleep crossing, the Premium economy rows are the value sweet spot, and the business suites rival anything Delta or BA put on the route. Mileage Plan members get the added bonus of earning toward oneworld status.
January and May are the sub-$650 windows on SEA-LHRMubboo original data
Two months sit roughly 30% below the summer peak.
We tracked fares across major booking platforms: January (post-holiday collapse) and May (pre-summer spring window) consistently produce the year's floors, often under $650 round trip in economy.
Four competing carriers keep the route flexible, so set a fare alert and pounce when one runs a sale. Avoid July and the December holiday return, when fares can run double a January seat. Shoulder months — March, September, October — sit near the $760 average.
Every carrier's cheapest fare strips the checked bag — price the bag, not the headline
The lowest fare on each airline is a trap if you check luggage.
Delta Basic Economy, Alaska Saver, British Airways Basic, and Virgin Economy Light all include zero checked bags. The gate or pre-paid bag fee then erases the $30 to $60 you saved on the fare.
For a transatlantic trip you almost certainly check a bag, so compare the Main / Economy Classic fares with one bag added rather than the headline number. The true price gap between the four carriers narrows sharply once bags are equal.
👥 Who flies this route — and what they should know
Budget economy flyer
Featured this monthRecommended: Delta or Alaska Main Cabin (not Basic/Saver), booked in a floor month.
Target January or May for sub-$650 round trips, and book a Tuesday or Wednesday departure to shave the fare further.
Avoid every carrier's cheapest bucket if you check a bag — the bag fee erases the savings. Base in Shoreditch or Camden for lower hotel prices and strong food markets, both a quick Tube ride from the center.
Don't book the far-out airport hotel to save £20 — the lost transit time isn't worth it after a long crossing.
Seattle tech or finance business traveler
Recommended: Alaska 787-9 business suite into Terminal 3.
For a Monday London meeting, the new Alaska lie-flat suite gets you horizontal across the 9h 25m crossing, and the 9:40pm SEA departure lands you mid-afternoon to adjust before sleep. You earn Mileage Plan from your home hub.
Base in the City or Clerkenwell near the financial core, a short Elizabeth Line ride from T3. If your miles live with Delta, take Delta One instead from the same terminal.
Don't book a tight same-day return — eastbound arrivals wreck the body clock.
Pacific Northwest outdoors traveler extending to the UK
Recommended: British Airways or Delta economy (not Basic), with onward rail.
If you're pairing London with the Lake District or Scottish Highlands, fly into the terminal that feeds your train. Ride the Elizabeth Line to central London, then King's Cross or Euston for onward rail north.
Check a bag for hiking gear, so skip Basic and Saver fares entirely. BA at Terminal 5 adds the deepest onward European options if you're hopping the Continent too.
Don't underestimate the 8-hour shift before a big hike — bank a recovery day in London first.
SkyMiles loyalist from the Pacific Northwest
Recommended: Delta or Virgin Atlantic on points, whichever has award space.
Because Delta and Virgin are one joint venture, your SkyMiles earn and burn identically on either — so hunt both for the open seat. Delta One and Virgin's Upper Class both deliver lie-flat from Terminal 3.
SEA's Delta hub status means frequent departures and strong SkyClub access before you fly. Set an alert when the schedule loads about 331 days out.
Don't split alliances mid-trip if you want lounge continuity at Heathrow.
First-time London tourist
Recommended: Delta or Alaska Main Cabin economy into Terminal 3.
A first London trip doesn't need a premium cabin — the crossing is short. Take the evening departure, sleep onboard, and ride the Elizabeth Line (£15.50) into the center on arrival afternoon.
Base in Covent Garden or the South Bank for walk-to-everything access to Westminster, the West End and the river. Buy nothing but a contactless tap for transit.
Don't pack day one with sights — the 8-hour jet lag hits hard; save the Tower and British Museum for day two.
Premium leisure couple celebrating an occasion
Recommended: Virgin Atlantic Upper Class on the A350-1000.
For a milestone trip, Virgin's Upper Class suite and onboard Loft social space are the most distinctive cabin on the route — more personality than Delta One for a similar SkyMiles award.
Fly the evening SEA departure for an onboard sleep, land in daylight, and base in Notting Hill or the West End for a romantic, walkable stay. It shares Terminal 3 with Delta.
Don't choose Economy Light on a celebration trip — it strips the checked bag you'll want.
⚖️ Flight delayed or canceled?
On the SEA outbound, US Department of Transportation rules apply.
Under the 2024 final rule, a canceled flight you decline to rebook must be refunded in cash, not vouchers. US DOT does not mandate EU-style compensation for delays.
For the London return, you depart a UK airport, so UK261 protections apply regardless of carrier. These can entitle you to cash compensation for long delays and cancellations within the airline's control, plus meals and care during waits.
Keep all documentation — boarding passes, delay notices, receipts — to support a UK261 claim. Travel insurance is worth considering on a long-haul trip; winter storms at either end are the most common disruption cause.
📱 Stay Connected — Travel eSIM for the UK
Free option: T-Mobile Magenta includes free UK roaming (throttled speeds — fine for maps, not video)
T-Mobile roams free in the UK but throttles data — fine for maps, slow for video. AT&T and Verizon charge $10 to $12 a day. A UK or Europe eSIM gives you real LTE data from about $5 a week, activated before you land at Heathrow.
🚗 Skip the Line — Private London Airport Transfer
Free option: Free alternative: the Elizabeth Line reaches central London for about £15.50 (~$20)
Arriving mid-afternoon after an overnight crossing with luggage? A pre-booked private transfer meets you at Heathrow arrivals and drives straight to your hotel — worth it for big groups, families, or first-timers who'd rather not parse the Tube map at hour 12 of travel.
🗺️ Day Trips Beyond London — Car Rental
Free option: Free alternative: direct trains reach Oxford or Bath from central London in under 90 minutes
London itself runs on rail, but a rental car unlocks the Cotswolds, Stonehenge, or rural pubs that trains reach awkwardly.
Remember the UK drives on the left, and central London charges a Congestion Charge — pick the car up outside the city for a countryside leg. Skip a car for London; consider one for a multi-day side trip.
Emergency contacts in London
What Travelers Are Saying About London
Based on recent discussions from r/travel, r/flights, and london community subreddits • Updated May 2026
👍 What Travelers Love
- r/travel · 2 posts
London offers unmatched access to affordable flights for weekend trips across Europe
— “catch budget flights to Europe for less than dinner costs”
- r/travel, r/london · 3 posts
The city blends historic charm with vibrant modern energy that captivates visitors
— “history and contemporary life merge seamlessly creating electric atmosphere”
- r/travel, r/london · 3 posts
London's pub culture and food scene exceed travelers' expectations
— “authentic pub experience and surprisingly good dining options”
- r/london · 2 posts
The city features world-class walkability and outstanding public transportation infrastructure
— “incredible pedestrian access and top tier transit system”
- r/london · 2 posts
Hidden architectural gems like tucked-away mews add unique character throughout the city
— “charming secluded streets offer delightful discoveries”
⚠️ Common Concerns
- r/london, r/travel · 3 posts
London's cost of living and prices for basics like beer are excessively high
— “prices are shockingly expensive especially for drinks”
- r/london · 2 posts
Londoners often place feet on public transit and venue seats creating hygiene concerns
— “people constantly put shoes on seats everywhere”
- r/london · 2 posts
Spring weather in London is unpredictable and changes dramatically throughout the day
— “weather swings wildly between extremes during spring”
💡 Trending Tips
- r/travel · 2 posts
Take advantage of budget airlines like Ryanair and easyJet for spontaneous European weekend getaways
— “book cheap carriers last minute for continental escapes”
- r/london · 2 posts
Explore London's charming mews and hidden side streets for authentic local atmosphere
— “venture into quiet tucked away neighborhoods for character”
Themes synthesized from public Reddit discussions. Quotes are paraphrased — never copied verbatim.
Frequently asked questions about Seattle to London flights
Four carriers fly SEA to London Heathrow (LHR) nonstop: Alaska Airlines, Delta, British Airways, and Virgin Atlantic.
Alaska is the newest entrant, launching daily 787-9 service on May 21, 2026 from its Seattle hub into Heathrow Terminal 3. Delta and Virgin Atlantic fly the route as a single SkyTeam joint venture, also from Terminal 3. British Airways operates its own widebodies into Terminal 5.
That four-carrier depth is unusual for a West Coast city outside California, and it gives Seattle flyers real fare competition plus a genuine alliance choice between oneworld and SkyTeam on one short transatlantic hop.
🎟️ Things to do in London
4,621 activities · Live data from Viator
The Ultimate Jack the Ripper Tour (Private Group Booking)
Heathrow Airport - To & From Central London - Meet & Greet
Private Tour to Stonehenge, Bath and The Cotswolds
The StrummerWalk
The Great British Pub Walking Tour: London
British Museum & National Gallery of London Semi-Private 8ppl Max
Researched by Mubboo Editorial Team · Reviewed by Richard Lee, Founder
Prices from Aviasales. Seasonal advice updated: May 2026 · Last editorial review: 2026-05-25 · Government info: travel.state.gov
Prices last updated 17h ago · cached fares aggregating 800+ airlines and agencies · Check real-time prices →
M verdicts are based on editorial research — not pulled from a database.