Thinking Phone Networks has landed $10 million more in funding from existing investors Bessemer Venture Partners and Advanced Technology Ventures.
The firms last year put $16.5 million into the Massachusetts-based UCaaS provider.
Thinking Phone said this latest round will allow it to expand international operations, including sales and support activities, and pay for ongoing product development. The company sells through channel partners.
Infonetics Research recently found that the global UC market will grow 21.3 percent in 2013.