You can check out the carry on specs allowable for most airlines here: http://www.travelnerd.com/...rry-on-luggage-sizes

These are the specs of the Orca Transition Bag: 60cm x 27cm x 28cm - so you can see it fits the specs for most airlines except for United.

Hope that helps! It's such a great bag for travelling with!

Thanks very much guys :-)