Lambeth North Station - closed since last July to allow the lifts to be replaced - reopened to passengers on Monday morning.
"I would like to thank customers and local businesses for their patience throughout the lift replacement work, which we have carried out as swiftly as possible," said Mark Wild, managing director of London Underground.
"The re-opening of the station with more reliable new lifts will improve transport connections in the area, benefitting local people, businesses and visitors alike."
Ben Stephenson, chief executive of WeAreWaterloo Business Improvement District, said: "We have been working with TfL to try to ensure the lift replacement works at Lambeth North are completed as soon as possible.
"We are very glad to see these works completed on schedule and would urge everyone to support the many local businesses in the area. They will be very pleased to see you!"