Airbus A350 vs Boeing 787: A350 economy seats are about an inch wider
The A350 and 787 look interchangeable on a booking page, but A350 economy seats run a median 18 inches wide against 17.1 on the 787. The extra inch comes from the fuselage, and Japan Airlines flies a 787 that beats every A350 anyway.
Key numbers
- A350 economy seats run a median 18 inches wide. On the 787 it is 17.1.
- Both fly nine-abreast, so the gap comes from the wider A350 fuselage.
- Japan Airlines' eight-abreast 787 beats every A350 here at 18.5 inches.
- Business-class width ranges from 18.7 to 35 inches whatever the airframe.
The short answer
In economy, the Airbus A350 is the wider seat. Across A350 configurations on SeatInside that publish dimensions, the median economy seat is 18 inches wide against 17.1 inches on the Boeing 787, and 31 of 33 A350 configurations reach 18 inches or more. Both aircraft normally fly nine-abreast, so the gap comes from the A350's wider fuselage rather than a different layout. The exception is Japan Airlines, which seats its 787s eight-abreast at 18 to 18.5 inches, wider than any A350 in the set. In business class the aircraft type is not predictive: seat width there ranges from 18.7 to 35 inches depending on which product the airline bought.
An inch of seat width separates them
Thirty-three A350 configurations on SeatInside publish economy seat dimensions. Thirty-one of them seat 18 inches or wider. Run the same query against the 787 and you get 48 configurations with a median of 17.1 inches, of which five reach 18.
Nine-tenths of an inch sounds like nothing until you multiply it across a nine-abreast row, where it adds up to about 8 inches. The A350 holds a 3-3-3 economy layout at 18 inches, and the 787 holds the same 3-3-3 at 17.1.
Airbus built the A350 fuselage wider than the 787's. Both manufacturers market nine-abreast as the standard economy arrangement, and nearly every airline took the standard on both aircraft, so the extra fuselage width goes straight into each seat.
Japan Airlines is the exception, and it is not close
Five 787 configurations here seat 18 inches or wider. All five belong to Japan Airlines, which lays out its 787-8 and 787-9 cabins eight-abreast in a 2-4-2 arrangement at 18 to 18.5 inches, wider than any A350 in the set.
The cost of that decision shows up in the seat count. A JAL 787-9 carries 195 passengers. An ANA 787-9 carries 395. Same airframe, same home market, and one airline is flying twice the people.
If the 787 is a JAL 787, take it over almost any A350.
In business class, the airframe is irrelevant
Business-class seat width across the configurations on SeatInside runs from 18.7 inches to 35, median 21. Pitch runs from 32 inches to 82. That spread follows the seat each airline ordered, not the aircraft type.
An A350 fitted with an older angled recliner loses to a 787 with a modern reverse-herringbone suite, and the reverse holds too.
Which one to book
For a nine-abreast economy cabin, default to the A350. You gain roughly an inch of shoulder room.
Then open the specific configuration, because the spread inside one type dwarfs the gap between the two. A350-900 cabins here run from 161 seats to 411, a 2.5x range on one aircraft.
Common questions
Is the Airbus A350 better than the Boeing 787?
In economy, yes, by roughly an inch of seat width. A350 configurations on SeatInside run a median 18 inches against 17.1 inches on the 787, with both aircraft normally flying nine-abreast. In business class the aircraft type is not predictive.
Which 787 has the widest economy seats?
Japan Airlines. It seats its 787-8 and 787-9 cabins eight-abreast in a 2-4-2 layout at 18 to 18.5 inches, wider than any A350 configuration on SeatInside.
How much wider is an A350 economy seat than a 787 seat?
About 0.9 inches at the median, 18 inches versus 17.1. Across a nine-abreast row that adds up to about 8 inches.
