I will be travelling via RER B from CDG to Paris. Will my RER ticket allow a transfer to a connecting Metro line or must I also purchase a Metro ticket for the final leg of the journey to my hotel? Thanks!

You can use it to go to any regular metro station - but not any RER station if that RER station is outside of central Paris - but IME any metro station - same ticket and do hang on to the ticket until you are out of the system as you may need it to trip turnstiles fantastic to get out of the system.

I used the same ticket to take RER to St Michel then walked over to Metro line

I theory you could be like that guy in Boston who rode the MTA all day - round and round - ticket is valid for as many transfers as you want - until you leave the system - that is the metro system but not RER stations outside central Paris - there you pay by distance or zone.

Like Michel-Paris says at times you even can exit the RER station and walk to a metro station to continue your journey -though i believe you are better off trying to use the underground passageways that link metro lines at stations - usually but in a few cases you do leave one system and then the same ticket lets you back into the metro if there are not passageways below or above ground.

Another thing you can not do is change from the RER to any of the tramways in Paris. I sometimes take the RER from CDG to "Cite Universite". When I do that I must either buy a new RATP ticket for the tram or use my "Navigo" pass.

Larry J

Larry - same is true for buses, right?

Just like in London

PalenQ

I think that is correct but to be honest in 5 years of living in Paris I have never changed from the RER to a bus. I always change from RER to the Metro or occasionally the line 3 tram.

Larry J