"This means no one will have to pay for a ticket anymore," mayor Aleksandar Sapic said Wednesday, with the city following the example of Luxembourg, the Estonian capital Tallinn and the French city of Montpellier.
Belgrade -- which has a population of nearly 1.7 million --- struggles with terrible traffic jams, with the number of cars on its roads increasing by 250,000 over the past decade, according to Sapic.
The Serbian capital is one of the few major European capitals without an underground mass transit system.
A metro system has been promised for 2030, although ground has yet to be broken on the project amid numerous delays.
Sapic also vowed that the city's entire fleet of buses, trams and trolley buses would be replaced by 2027.
Last month the mayor's plans to demolish a major World War II-era bridge triggered protests and criticism that the removal of the river crossing would only exacerbate the city's traffic problems.
The measure announced Wednesday was the latest in a series of handouts greenlit by Belgrade's municipal government backed by the ruling Serbian Progressive Party. Over the past year kindergartens have been made free and students in the capital have also been given financial aid.
