Compare all airlines

All 16 airlines, side by side: seat width, seatbelt length, extenders, and second-seat policy, verified June 11, 2026, sortable by any column.

Tap a column heading to sort. Width shows the narrowest published figure first: the number safe to plan around. Why we lead with the smaller number.

Airline Economy width Seatbelt Extender Second seat
American Airlines 16.2–18.7 in Not published Yes Second seat at same fare; call ahead
Delta Air Lines 17.3–18.6 in Not published Yes Extra seat expected if encroaching
United Airlines 16.3–18.4 in Not published Yes Extra seat required if encroaching
Southwest Airlines 15.5–17.8 in Not published Yes Free at airport only if seats open (2026 policy)
Alaska Airlines 16.3–18.2 in 46 in Yes Second seat; refunded if flight had open seats
JetBlue 17.8–19 in 45 in Yes No size policy; extra seat optional
Spirit Airlines (ceased operations) 16–17.5 in Not published Yes Historical: airline ceased operations
Frontier Airlines 16.5–19.1 in Not published Not published Second seat required if encroaching
Allegiant Air 17–17.8 in Not published Yes Second seat at booking; armrest test
Hawaiian Airlines 16.5–18 in Not published Not published Second seat; refunded if flight had open seats
Air Canada 17–18 in Not published Yes Free extra seat within Canada (medical form)
British Airways 16–18 in Not published Yes Extra seat required if you cannot fit
Lufthansa 17–18 in Not published Yes Second seat at net fare; book by phone
Air France 16–17.7 in Not published Yes Second seat 25% off; refunded if flight not full
KLM Royal Dutch Airlines 16.3–18.1 in 42.1-61.0 in Yes Extra seat ~75% of fare via customer service
Aer Lingus 17–18 in Not published Yes Extra seat at full fare

Every number above is a summary. Each airline's page carries the per-aircraft figures, the full policy in plain language, and a link to every source.

Only 3 of 15 operating airlines
publish their seatbelt length.

If that strikes you as low, it is. And it's the single number an anxious traveler most wants the night before a flight.

Who actually publishes this?

This table is the accountability view: does the airline publish seat widths, seatbelt length, and an extender policy on its own website? "No" means we looked and it isn't there, not that we didn't check. And where the answer is "No," we ask the airline directly: the Asked column tracks who we've asked, when, and who answered. Silence is part of the record. How we treat direct answers.

Airline Widths Belt Extender Asked
American Airlines Yes No Yes Not asked
Delta Air Lines Yes No Yes Not asked
United Airlines No No Yes Not asked
Southwest Airlines Yes No Yes Not asked
Alaska Airlines Yes Yes Yes Not asked
JetBlue Yes Yes Yes Not asked
Spirit Airlines No No Yes
Frontier Airlines Yes No No Not asked
Allegiant Air Yes No Yes Not asked
Hawaiian Airlines Yes No No Via Alaska
Air Canada No No Yes Not asked
British Airways Yes No Yes Not asked
Lufthansa No No Yes Not asked
Air France Yes No Yes Not asked
KLM Royal Dutch Airlines Yes Yes Yes Not asked
Aer Lingus Yes No Yes Not asked

The 3 who do: Alaska Airlines, JetBlue, KLM Royal Dutch Airlines.