I know this topic has been covered, but I can't find a recent thread that I thought said there are now machines @ CDG that will take a US non-chip credit card - one with a magnetic strip. I know you can go to the ticket counter and they will take a magnetic strip US credit card, but wanted an alternative should there be a long line. Additionally do the machines now take bills as well as coins? Thanks!

You can try. The métro station ticket machines now accept the non-chip card.

The new RATP machines in Paris take banknotes, but the RER at CDG is operated by the SNCF, so I don't think they take bills. However, there is apparently a bill changer next to the ticket machines... somewhere or other.

The ticket machines at Terminal 2 will not accept magnetic strip credit cards. You must have a chipped card. Some chip and signature cards will work with a pin (if you have one) and some chip and signature cards work without a pin. If you have a chip and signature card, you will need to ask your bank about kiosk purchases.

The ticket machines at Roissypol, along the CDGVAL free rail line, did, as of last year, accept magnetic strip credit cards. If they no long accept these types of cards, the service window line is never really very long and generally moves along rapidly.

My US Bank Visa chipped card works in ticket machines (SNCF, Métro, Transilien) with no PIN required.