This interruption, which will last until spring 2027, means that users will have to make the connection between both lines via the street, following specific signage. Transports Metropolitans de Barcelona (TMB) reminded of this measure, which affects one of the key points of the Catalan capital's metro network, used daily by some 12,000 people.

The closure at Plaça de Sants adds to the one already in force at Verdaguer station, where the transfer between lines L5 and L4 is also made externally due to works. These actions are part of a project with a budget of 15.2 million euros.

The planned improvements at Plaça de Sants include the expansion of the existing lobby and the installation of three new elevators: one to connect the lobby with the street and two to link the lobby with the platforms and the interchange corridor with L1. In addition, two new emergency exits will be built from the platforms, one leading to the lobby and the other directly to the street.

Other notable actions include the enlargement of the Plaça de Sants access, the widening of the stairs connecting the lobby level with the pre-platform level, the improvement of the platform raising to reduce the distance to the trains, the implementation of tactile paving for people with visual difficulties, and the installation of a new fare barrier with wider passages.