The Red Line, which usually ceases service between roughly 1 a.m. and 4:30 a.m., will run every 20 minutes until 3 a.m. on Fridays and Saturdays until Dec. 27, according to the Metropolitan Transportation Authority.
"With these extended hours, holiday shoppers and party-goers can enjoy Hollywood, downtown and other Red Line destinations without traffic or parking hassles," said Los Angeles City Council President Eric Garcetti.
The six-weekend pilot program, which will cost $4,500 per night, was funded by businesses and entertainment venues along the subway's route.
Metro spokesman Dave Sotero said the decision to continue the extended hours would be up to the businesses involved in the project.
"I think they're going to look at whether this brings more people through their doors," Sotero said.
Operating hours for other Metro lines, including the Purple Line -- which shares track for part of its route with the Red Line -- will not change.