How bif are the seats on Iceland air?

I checked with SeatGuru, and it looks as though the seats on their 757-200s are 17.2" wide in Economy Class, with a 32" inch pitch. If you upgrade to Economy Comfort Class (don't know if that is an option for you) the seats will be 20" wide with a 33" pitch. Here's the link: http://www.seatguru.com/airlines/Icelandair/Icelandair_Boeing_757-200.php I don't know their policy for accomodating larger flyers, but if I were you, I would call and find out.

Flew Iceland Air this past Fall. Bad knee so I booked Economy Comfort Class. Very roomy. Economy class seats are pretty standard so at 300 lbs you're pretty much toast. No, make that you're very much toast. Upgrade my friend. My husband flew in economy and he's 6' plus but trim. Cramped but not horrible. Thought the service was good and everything was very efficient (boarding, luggage etc.).

I just flew Iceland Air about two weeks ago. I would say they have one of the smallest seats I experienced in Economy class.

Been a few years, but if their seats are 17.2" wide, that's fairly standard for a 757 (maybe even a tiny bit bigger than average...most are approx. 17"). If you can fit into United's or any other airline's 757 seat, you'll be fine. If you're worried about it, check out an upgrade as already mentioned. Not only do you want to be comfortable, I'm sure you wouldn't want to jack up a fellow passenger's comfort if the arm rests can't go down or you're otherwise taking up part of another's seat that they paid for. Saga Class will give you a bigger seat, a better menu, better service (but it's already outstanding on Icelandair), lounge access at the airport, etc.