IMPORTANT! As of January 1, 2021, telephony options are available only to Bitrix24 commercial plan users. Please see Bitrix24 pricing page for current information.
Bitrix24 is free call center software unlike any other. If you choose a cloud version, you can start calling and receiving phone calls within minutes. You pay only if you need to have more than 12 employees, want to rent a phone number, SIP connector or use Bitrix24 telephony for outbound calls. You can also purchase self hosted editions of Bitrix24 if require source code access or would like to deploy Bitrix24 on premise.
* Please note that the information may have changed since the publication. For current prices and features please visit Bitrix24 pricing page.
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For more technical information, please refer to Bitrix24 manuals regarding how you can set up Bitrix24 as cloud or self hosted call center software.