I believe its eight
Never seen a 12 person raft.
I agree with Brian. It also depends on the nature of the people on the trip. You do have to paddle, and follow instructions.
I'm sure you can do 12 in one raft. But I think for a better experience you would want to take two rafts. The guides will make it fun for you. And you will never be that far apart.. Hope you have a great time.. I know you will.
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