One of the big savings with a VoIP service is the charge for international calls. Some plans even include an array of included countries for one low monthly charge. Inquire about the cost of international calls, especially the per minute charge to the countries that you most likely be calling. Low International rates are one of the big VoIP benefits of VoIP service and unless you are certain that you will not be calling International, then this could be an important factor, especially for business accounts. Some companies can save enough that VoIP, even a single SIP trunk, should be one of their top budget saving ideas.
Actually VoIP call rates depend on VoIP service provider. Someone is using low quality route or non cli route or gray route and someone is using quality route or white cli route. Non cli or Gray route and CLI or White CLI route calling rate are so many difference. Suppose white cli route is 0.0100$ per minute and other hand non cli or gray route rate will be 0.0045$ to 0.0060$. So call rate depends on quality.
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