This may be a "no brainer", but I'll ask anyway and hope for well reasoned answers: I'll be in Paris throughout all of March and plan to buy the Navigo Pass so I will have access to all 5 zones, as I want to explore areas away from the center of the city. I also plan to do some longer day trips, such as to Chartres, Lille, Bruges, Strasbourg, etc. Should I ride as far as I can using the Navigo and pick up a different ticket from the last station to go on to my final destination, wherever that is? If I do an advance search and recognize that I might have some wait times between trains, that seems to me to be the most cost efficient option. Yes? No? Why or why not? Thanks.
Use your Navigo to take the Metro to the rail station that serves the destination. That will be your most efficient option in terms of time and cost.
No, your best price will be to buy an advance nonrefundable ticket, then use the Navigo to get to the appropriate departure station in Paris. Lille and Bruges will be Gare du Nord, Chartres will be Montparnasse, and Strasbourg will be Gare de l'Est. Chartres might be an exception, but the others will be express trains that probably do not stop anywhere else in the Paris RER district.
Brenda,
As you already know the Navigo Decouverte Pass covers Zones 1-5 within Paris:http://parisbytrain.com/wp-content/uploads/2013/01/rer_zones.pdf
You can travel as far as Versailles & CDG airport. I suppose you can take a train from CDG to some of your desired destinations, but it doesn't make much sense to have to transfer & wait for a different train, if you can just take a train directly from the respective Paris train stations.
Yes, you could save 2.50 EUR each way by going to Versailles Chantiers on the RER C and changing to the TER train there. But the RER C will take a while as it makes the 10 or so stops along the way to get there. 45 minutes or so is my guess. But if you cough up the extra 2.50 EUR and board the TER at Montparnasse, that train goes nonstop to Versailles Chantiers in 16 minutes and then continues on to Chartres. So I'd say it will cost about an hour each way. What is your time worth?