Last Sept, I sent my 2 cats by Continental, which I felt the most comfortable with, after speaking with BA, Northwest, etc. Cats from Atlanta GA to London Gatwick--the freight charges were $539 each, and there was a $175 fee for the broker/agency that would "clear" the animals through customs. All we had to do was pick the cats up at the Animal Reception Center--with no more fees to pay. I think Continental charged by the size of the container, not weight. The cats are 10 and 15 lbs each, and in their travel containers, they weighed 11.8 kg and 10 kg, but freight was still $USD 539 each.