Cost of RER from CDG to central Paris for children? By | May 15, 2018 | in Vote Up 0 Vote Down Answered Public Public Private Questions Anonymous asked May 15, 2018 How much does it cost for a child from CDG to central Paris on the RER? 1 answer Vote Up 0 Vote Down Public Ben ⋅ Staff ⋅ May 16, 2018 7.20€ per child RER ticket (9 and under) for CDG to Paris train. #1 Please login or Register to Submit Answer Username or Email Address Password Remember Me