The most cost-effective way to make calls from the United States to Paris is to use an application such as Viber or Facebook messenger to call over Wi-Fi or data. If those options are unavailable, several other applications are available for international calling, including Skype and Google Voice.
There are several options available for individuals who want to make international calls and save money while doing so. Viber is an application for smartphones that allows users to find their friends and contacts and call them for free over the Internet. Since no cell networks are used for the calls, location doesn't matter, and calls are made to and from anywhere as long as there is an Internet connection. Additionally, Viber offers calls to individuals without the program. To call someone in France, this costs 4.3 cents per minute to a cellphone and 2.1 cents per minute to a landline, as of April 2015.
Facebook messenger offers a similar functionality integrated into the Facebook or Facebook Messenger smartphone applications. Like Viber, calls are made to anyone anywhere as long as there is Internet availability.
Skype and Google Voice, unlike Facebook and Viber, do not offer free international calls but offer relatively low rates. Skype rates are 2.8 cents per minute to France from the United States, with subscription options available. Google Voice charges 3 cents per minute for calls to France.