Southwest first announced its plan to serve Hawaii in October 2017 and has been waiting for a green light from the Federal Aviation Administration, a process that was delayed in the 35-day partial government shutdown that furloughed safety inspectors at the agency.
The airline needed the FAA to sign off on its plans to fly Boeing 737-800 jets over water for long distances, away from airports where jets could make emergency landings. It announced the approval shortly before the market closed on Wednesday.
The airline will announce flight schedules and start selling tickets to Hawaii in the coming days, it said.
Southwest plans to fly to the islands from four California cities: Oakland, San Diego, San Jose and Sacramento and fly to Honolulu, Kahului on Maui, Kona, and Lihue on Kauai. The airline also intends to offer service between the islands.
Southwest shares were up 4.8 percent in afternoon trading. United Airlines and Delta Air Lines were each off less than 0.5 percent, while American Airlines was up 0.5 percent. The NYSE Arca Airline Index, which tracks 15 airlines in the Americas and Europe, was down 0.3 percent.