It says that it is not possible to book an extra seat in the Premium Economy and Business cabins https://wwws.airfrance.de/en/information/passagers/forte-corpulence, in Economy it's ok. But it can changes according to different companies
Book two seats Please contact our Saphir service so that they can assess your situation, check if a seat belt extension is necessary, and complete your booking with you.
If you are traveling in the Economy cabin on one of our long-haul flights, and the width of the seat is not sufficient for you, Saphir will offer you a second seat next to yours. This second seat will provide you with greater comfort, while ensuring your safety with a seat belt extension.
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Please note: in the Premium Economy and Business cabins, it is not possible to book an extra seat with a seat belt extension, due to the seat configuration and static armrests.
In the Economy cabin: passengers cannot book two seats side by side and for the same person using our online booking system.
