Bitrix24 is a free virtual phone system created specifically for small businesses that works in 43 different countries, including USA, Canada, UK and Australia. You can rent local ($4/mo), toll free ($6/mo) and international phone numbers ($11/mo) or connect it to your own PBX (office or virtual) in order to use your existing phone number(s).
The range of features available to you is identical to what regular office phone system gives you – caller ID, employee extensions, call queues (aka call management or call cascading), intelligent call routing, voice mail, call transfers, greetings, holding, call forwarding, call to all available agents (simultaneous call distribution), call recording (including recording warning message), call analytics and so on.
Unlike other virtual phone systems, Bitrix24 comes with a free CRM as well. This means that calls from existing clients are automatically routed to managers assigned to each individual customer. A manager can easily see a history of interaction with a particular client or a prospect. New sales managers can listen to past recordings in order to familiarize themselves with existing clients. Future calls can easily be scheduled in Bitrix24 calendar. With all these features, no wonder Bitrix24 is free virtual phone system for small business #1.
Bitrix24 CRM manual is available here.
If you are interested in buying self-hosted editions of Bitrix24, which come with API, CMS and source code, can be easily customized and integrated with other tools, please download a trial version here.