What's the cheapest month to go to Hawaii?

September and early October are consistently Hawaii's cheapest travel months. Summer peak season ends after Labor Day, kids return to school, and airlines drop fares before the holiday surge begins. Flights from the West Coast can drop to $300–500 round trip versus $600–900 in peak season. Hotel rates follow the same pattern — mid-tier Waikiki hotels run $180–250 in September versus $280–400 in December. The weather in September and October is warm and dry with light trade winds. Whale watching is not available (that's December–April), but snorkeling, surfing, hiking, and helicopter tours are all excellent. Avoid February, March, spring break weeks, and July — these are peak season with the highest prices and most crowds.