Fly from Denver to either Honolulu, Oahu or Kahului, Maui for $353 round-trip on American and Delta Airlines.
This is a great fare targeting the United Hub at Denver, fares may not last long so if you are interested you should consider booking soon. This fare is available year-round with blackout dates in the peak Summer months and during peak Holiday times. Travel is available on any day of the week, Monday through Sunday. No minimum stay is required. This also books into American Airlines Regular Economy class, so you will be entitled to that carry-on, however, checked baggage will cost additional.
While searching on AA.com we found seats departing DEN on Saturday, October 20 and returning from HNL on Sunday, October 28, 2018.
Another neat thing about this fare is you could do an open-jaw itinerary and fly into Honolulu HNL and out of Maui OGG for the same price. Of course, you would have to pay for the interisland flight which is about $70 one-way, thus letting you see two Hawaiian Islands for only $423 total!
We also have a list of other great deals departing Denver DEN on the flight deals page here.