As of June 16, 2020, it is no longer mandatory to have a certificate from your employer to travel on public transport in Paris (bus, tram, metro, trains and RER) during rush hour. Following the transition of the Île-de-France region to a green zone, this regulation is no longer applied.
From Tuesday, June 16, 2020, you can freely take public transport in Île-de-France during rush hour. Masks remain mandatory on all public transportation for anyone over the age of 11 or face a fine of €135. Maintaining physical distancing must also be respected.