Spirit Airlines will operate about 20 flights on Thursday after its pilots made a deal to end their strike.
Flights will begin at 4 p.m. EDT, and Spirit expects to resume full service on Friday.
Spirit pilots had been negotiating for more than three years before the strike started Saturday morning. The union said first officers in particular lagged their counterparts at other low-cost airlines like JetBlue Airways Corp. and AirTran Airways.
Negotiations resumed on Tuesday afternoon and lasted until early Wednesday morning, said Sean Creed, a Spirit captain and head of the Air Line Pilots Association unit there. A tentative deal came around midday, he said.
Strikes at U.S. airlines are rare because of strict federal rules aimed at keeping the transportation system moving. The last strike at a major carrier was a walkout by Northwest Airlines mechanics in 2005.
Spirit operates about 150 daily flights in the United States, Latin America and the Caribbean.
The carrier is privately held and based in Miramar, Fla. It carries about 16,000 passengers per day, or about 1 percent of the nation's air traffic.
Spirit says passengers with travel plans for Friday should confirm their flights at .