Pay attention to Rain Service Details:
The direction of this service is from Iran to outside, so you can not call Iran using this service, but you will have a national number inside Iran and you can receive calls from Iran if anyone call that number in Iran.
Your credit never expires.
There is no hidden fee, no connection fee, no extra fee.
Rates to receive calls from Iran is 1.9 Cent/Min.
These are the lowest real rates in the market, if you know cheaper rates, please let us know to beat it, if it is a real rate and works.