Verizon, AT & T, Sprint, T-Mobile are offering free of charge to call Nepal.
Please call your service provider to open service for you before you make a call.
Please be sure Not to call after specified date set by your service provider to avoid charge.
Please be sure to turn International-Call Service off after free call period ends to avoid charge.
Free call period
AT & T, Sprint, and T-Mobile – April 25th through May 16th.
Verizon – April 25th through May 31st.
Time Warner Cable: All calls placed by Time Warner Cable’s Home Phone and Business Services customers to land-line and mobile numbers in Nepal will be free through April 25th to May 25th.
Call free to Nepal using Skype to land-line, or mobile
Call free to Nepal using Viber-Out, Google to land-line or mobile
http://mashable.com/2015/04/27/google-viber-reduce-call-costs-to-nepal
Here are the companies offering free or discounted calls to Nepal
http://www.theverge.com/2015/4/27/8505065/nepal-earthquake-free-calling-microsoft-google-skype