Can I purchase one at CDG?

Thanks!

Sure! But you can also wait until you're in Paris and save a few Euros. What's the rush?

Excusez-moi! You can purchase a sim card at CDG, but not a prepaid cell phone. You will have to wait until you get into Paris.

Prepaid SIMs are available at the Relay stores. There is a Virgin store in Terminal 2A that might sell phones but with more and more people already carrying multi-band capable GSM phones, the market for ubiquitous distribution of mobile phones has diminished (which is one of the reasons Phonehouse closed all of its stores).

Where in Paris? Maybe Monoprix?

Are you asking about phones or SIMs RonZ? Monoprix does not sell electronic items. FNAC or Darty would be better locations or one of the SFR, Orange, or Bouygues boutiques. If you need a GSM phone, they are sold on eBay and other such locations where you might live.

There's a SFR, ORange, or Bouyges store on every corner in the city and that's where you'd buy the phone. SIM is available in Relay stores in all the big stations - CDG, Gare de Lyon, etc.

It's not just a question of GSM, it can be a question of cost. Look into what your carrier charges for international calls made from international locations - often not the same as if you'd called internationally from home.

I have an old fashioned cell phone that is not compatible with any international service. I need something to use in Italy for a possible call or two. I'll be in Paris first.