Most visitors arrive at Daniel K. Inouye International Airport (HNL) in Honolulu on Oahu. It is the main hub with direct flights from the US mainland, Japan, South Korea, Australia, New Zealand, and other Pacific destinations. Flight time from Los Angeles is about five and a half hours; from Tokyo, about seven hours.
Maui's Kahului Airport (OGG) also receives direct flights from several US mainland cities, which saves you from having to connect through Honolulu. The Big Island has two airports: Kona International (KOA) on the west side and Hilo International (ITO) on the east. Kauai's Lihue Airport (LIH) has some direct mainland routes as well.
From the US West Coast, fares are most competitive. Hawaiian Airlines, United, Delta, American, Southwest, and Alaska Airlines all serve Hawaii. From the East Coast, expect a connection or a very long direct flight. Japanese carriers like Japan Airlines and ANA fly to Honolulu from Tokyo and Osaka.
There is no ferry service from the mainland. A few cruise lines include Hawaii on Pacific itineraries, but flying is the only practical way to get there.