transatlantic · 9h 30m · 7,750 km
Seattle to London
2 airlines · 2 aircraft ranked
In business class, Delta's Delta One Suite (A330-900) dominates the field with a 8.5/10.In premium economy, Delta's Delta Premium Select (A330-900) leads the field with a 5.3/10.
Quick pick
Fly Delta. It has 9 more inches of legroom and a wider seat (22.5" vs 18").
A noticeably better product that justifies the pick.
Fly Delta. It has free Wi-Fi (paid on British Airways).
If fares are comparable, this is the better cabin.
Fly Delta. It has free Wi-Fi (paid on British Airways).
If prices are similar, go with this one.
Select two airlines to compare head-to-head
Data verified June 2026
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Airlines on this route
Route insights
- In business class, Delta's Delta One Suite (A330-900) dominates the field with a 8.5/10.
- In premium economy, Delta's Delta Premium Select (A330-900) leads the field with a 5.3/10.
- In economy, Delta's Main Cabin (A330-900) leads the field with a 4.9/10.
Frequently asked
Which is better in business: Delta or British Airways on SEA-LHR?
Delta One Suite (Delta Air Lines, A330-900) dominates Club World (British Airways, 777-300) in business, scoring 8.5/10 vs 5.5. The deciding factor: a 80"-long bed vs 72".
Which is better in premium economy: Delta or British Airways on SEA-LHR?
Delta Premium Select (Delta Air Lines, A330-900) edges out World Traveller Plus (British Airways, 777-300) in premium economy, scoring 5.3/10 vs 4.7. The deciding factor: AC + USB-C vs USB-A only. British Airways fights back on seat width.
Which is better in economy: Delta or British Airways on SEA-LHR?
Main Cabin (Delta Air Lines, A330-900) edges out World Traveller (British Airways, 777-300) in economy, scoring 4.9/10 vs 4. The deciding factor: Free Wi-Fi vs Paid Wi-Fi.
What are the best seats in Delta Delta One Suite on SEA-LHR?
Best: Odd-numbered window seats (1A, 3A, 5A, 7A and equivalent on right side) are positioned closer to the window and farther from the aisle, offering maximum privacy. Center pairs work well for couples when the privacy divider is lowered. Avoid: Seat 8A is an orphaned solo window seat in the last row of the cabin -- good for solo travelers but isolated. Even-numbered window seats are closer to the aisle with less privacy. All 29 passengers share only 2 lavatories, a significant downside vs the A350. 29 staggered suites with sliding privacy doors and do-not-disturb indicators. Memory foam cushions on all beds. 18.5-inch seatback screen is among the largest in the industry. Only 2 lavatories for the entire business class cabin is a notable weak point compared to 4 on the A350.
What are the best seats in Delta Delta Premium Select on SEA-LHR?
Best: Row 20 bulkhead has the most legroom. Window doublets (A-B and H-J) are ideal for couples. Row 23 passengers can stand behind their seat and still view IFE. Avoid: Center seats (D-E-F) in any row, especially in row 23 which is closest to the economy cabin partition. 28 seats in 4 rows. Premium amenity kit, enhanced meal service, and dedicated flight attendant. Adjustable headrest with privacy wings. USB-A and AC power at every seat.
What are the best seats in Delta Main Cabin on SEA-LHR?
Best: Delta Comfort+ rows 30-36 (56 seats) offer 34 inches of pitch with extra legroom, priority boarding, and dedicated overhead bins. Row 30 bulkhead has the most space. Window doublets (2-abreast) on each side are great for couples. Avoid: Last 2-3 rows near rear lavatories and galley. Center block middle seats (E and F in the 4-abreast center) are worst on long flights. 2-4-2 layout is more comfortable than 3-3-3 on competing aircraft for couples -- no middle-seat risk in the side sections. 56 of the 224 economy seats are Delta Comfort+ with extra pitch. Complimentary meal service on international flights. Delta Sync free Wi-Fi for SkyMiles members.
What are the best seats in British Airways Club World on SEA-LHR?
Best: The mini-cabin (rows 5-7) has only 12 seats and is the quietest and most private. Window suites (A or K) in rows 9-12 create a genuine cocoon with the door and fuselage wall. Row 5 gets priority meal service with the widest choice of entrees. Avoid: Partial rows 18 and 24 only have center seats and lack window positions. Back rows of each cabin section near galleys experience more noise. Bassinet positions at 8K and 19A/K may mean infants nearby. Row 24 gets meal service last. 76 Club Suite seats across three separate cabins, making this BA's largest business class. All 16 777-300ER frames are now retrofitted. The Club Suite has a larger 18.5-inch IFE screen than First class. Every seat has a door, direct aisle access, and Bluetooth audio. Center pairs have retractable dividers for couples.
What are the best seats in British Airways World Traveller Plus on SEA-LHR?
Best: Row 31 offers the sweet spot between bulkhead legroom and avoiding bassinet noise. Window pairs (A-B, J-K) provide the most privacy. Avoid: Row 30 bassinet position means possible infant noise. Row 34 (last row) has limited recline and proximity to economy partition. Center seats D-E-F-G are least desirable. 40-seat premium economy in 8-abreast 2-4-2 configuration. Adjustable headrests with wings. Complimentary meal service with upgraded wine selection. Dedicated cabin crew. USB and AC power at every seat.
What are the best seats in British Airways World Traveller on SEA-LHR?
Best: Rows 40-42 are the front of economy, furthest from the rear galley. Exit row seats offer more legroom. Avoid: Last 2-3 rows near rear galley and lavatories are noisy with limited recline. Middle seats (B, E, H) in the 3-3-3 layout are least desirable. Row 53 typically has no recline. 9-abreast economy at 31-inch pitch on the 777-300ER. Complimentary meals and beverages on all long-haul routes. Seatback IFE with USB charging. The 777-300ER is BA's flagship long-haul aircraft.