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Join Date: Jul 2002
Location: MCI
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American and United allow open-jaw on award tix, but they do not allow a circle trip or a stopover within the islands. (You can certainly stopover at the gateway city if you like - we've done this on Hawaii awards before.) You have to pony up the extra 5K or buy your one-way interisland ticket.
I guess that's not a big deal: getting the open-jaw is the most important thing to a multi-island visitor because you have to waste half of your last day in Hawaii backtracking to another island just to catch a flight.