Close.io, With built-in calling, SMS, and email all in one platform, Close.io is designed to help the customer close more deals.
Current Customer(s)
Market Share (Est.)
Ranking
The top three of Close.io’s competitors in the VoIP And SIP category are Skype with 21.64%, CallRail with 16.19%, Cisco WebEx with 13.18% market share.
Popular Comparisons
The top three of Close.io’s competitors in the VoIP And SIP category are Skype with 21.64%, CallRail with 16.19%, Cisco WebEx with 13.18% market share.
Close.io vs Skype
Close.io vs CallRail
Close.io vs Cisco WebEx
Close.io vs Cisco VoIP
Close.io vs Cisco Unified Communications Manager (CallManager)
Close.io vs Genesys PureCloud
Close.io vs RingCentral
Close.io vs Google Voice
Around the world in 2026, over 268 companies have started using Close.io as VoIP And SIP tool.
| Customers | Employee Range | City | Region | Country | Social Links |
|---|---|---|---|---|---|
| 10,000+ | Hamburg | Hamburg | Germany | ||
| ProntoPro | 10,000+ | Milan | Lombardy | Italy | |
| Upwork | 10,000+ | San Francisco | California | United States | |
| LMU Munich School Of Management | 10,000+ | Munich | Bavaria | Germany | |
| Microsoft | 10,000+ | Redmond | Washington | United States | |
| Doterra | 10,000+ | Pleasant Grove | Utah | United States | |
| Crossover | 5,000 - 9,999 | Austin | Texas | United States | |
| Kaseya | 5,000 - 9,999 | Miami | Florida | United States | |
| Toptal | 1,000 - 4,999 | San Francisco | California | United States | |
| Freedom Forever | 1,000 - 4,999 | Temecula | California | United States |
The top three products and services offering customers that use Close.io for VoIP And SIP are Saas (12), Marketing (11), Digital Marketing (10).
Customers
The majority of Close.io's customers for the voip category fall in the company size of 100 - 249 employees (85 companies), 20 - 49 employees (74 companies), 0 - 9 employees (46 companies).
Employee Size
The top three geographies of Close.io for voip are the United States with 153(64.02%), Germany with 18(7.53%), Canada with 15(6.28%) customers respectively.
Customers
Find answers to the most often asked questions by users.
Who are the top Close.io competitors?
Close.io’s Top competitors in the voip category are Skype, CallRail, Cisco WebEx. You can view a full list of Close.io competitors here. 6sense uses advanced data mining and AI algorithms to track customers and competitors of Close.io and 40,000 other technologies on the internet. You can also compare Close.io and its feature with top competitors here : Close.io vs Skype Close.io vs CallRail Close.io vs Cisco WebEx.
What is Close.io customer distribution based on company size?
What is Close.io market share in the voip?
What are the top countries that use Close.io?
What are the top industries that use Close.io?
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