Is there an airline that goes from Phoenix, Arizona to Seattle,
Washington that allows pets?

I have an 11 pound Chocolate Point Siamese cat that (while in a
carrier)would fit nicely under the seat in front of me.  I would NOT
want to place "Sammy" in the cargo hold where I've heard they place
large dogs, etc.

lina2...

Quite a number of airlines ( I would say most ) allow you to bring a
pet onboard provided they are in a regulation carrier (soft mesh type)
and are under a certain weight. All pets in carriers must fit under
the seat in front of you.

A couple of years ago, I travelled with my cat, Albert. The airline I
took( Air Canada )charged me another $ 65.00 cash each way for my cat.
This had to be paid at check in.

The only real problem I had was that I had to take my cat out of the
carrier at security so they could scan the carrier. He was shaking and
I almost thought he would jump out of my arms. A good idea would be to
put a harness on your cat and a leash so that if he accidently jumps
out of your arms, you won't lose him.

Albert was great on the flight and no one around me had any problems.
Do make it a point to tell the flight staff that you have a cat with
you though, just in case someone in the seat next to you has
allergies.

Good luck and happy travels with your cat.

Steph53