United partners with both Hawaiian Airlines and Island Air to offer codeshares within Hawaii.
You can redeem United miles for interisland flights on either airline. The cost is 6,000 miles + $5.60 one way.
You can also include Hawaiian or Island Air flights as part of a larger award, like Newark to Honolulu on United, connecting to Molokai on Hawaiian. Until very recently, though, United would price this as two separate awards. It would be 28,500 United miles in economy: 22,500 for mainland to Hawaii + 6,000 interisland.
Basically you got charged for two awards every time you booked a trip that included an interisland flight and another airline.
Since this was the only partner’s flights which always broke awards, the punitive policy made no sense. It wasn’t a mistake, though, as it was reflected on the award chart on united.com.
Now, however, the United award chart has dropped mention of charging extra miles for interisland flights as part of a larger award.
And united.com has stopped adding 6,000 miles to awards that include an interisland segment.
For instance, this award from Los Angeles to Hilo on a combination of United and Hawaiian flights is 22,500 miles. Until recently, it would have been 28,500 miles.
Hawaiian Airlines and Island Air award availability is excellent on all of their routes. For instance, there is award space every day for the next two months from Honolulu to Kona.
And that’s not just one flight per day. There were 31 itineraries found (nonstop plus connecting) on a single day that were bookable with United miles.
What You Can Do
You can search on united.com for awards from your home airport to anywhere that Hawaiian or Island Air fly. You can book awards that contain United economy Saver award space plus insterisland award space for 22,500 United miles each way or United First Saver award space plus insterisland award space for 40,000 United miles each way.
You can also book a roundtrip United award to Hawaii that includes a free stopover in Hawaii.
For instance, on this trip from Los Angeles to Honolulu to Kahului to Los Angeles, you’d get a week on Oahu and a week on Maui.
The Honolulu to Kahului flight adds zero miles to the cost.
The total price is 45,000 miles and $11. It would have cost 63,000 miles and $17 under United’s old award rules. (Note that as constructed above there are three interisland flights, so 18,000 extra miles would have been needed under old rules.)
What You Can’t Do
You cannot book the United-plus-interisland awards with any other type of miles. I always advocate booking United flights to Hawaii with Singapore miles because Singapore can access the exact same United Saver award space and charges fewer miles. But Singapore doesn’t partner with Hawaiian or Island Air, so you can’t book the awards discussed in this post with Singapore miles. (It doesn’t matter that Singapore partners with United which partners with Hawaiian; there is no transitive property of miles.)
You also can’t fly into one Hawaiian island, layover for 23 hours and fly to the next unless united.com offers you that or you count the layover as your stopover. You used to be able to construct awards like that purposely to see more destinations on a single award, but now United treats long layovers that aren’t offered on united.com searches as stopovers.
United has made a customer friendly change by eliminating its previously very customer unfriendly practice of charging a separate award for every intra-Hawaii flight even when that flight was part of a larger award.