Mobile devices are at the heart of how almost all businesses communicate and are now, more often than not, the device of choice for users.

Despite the flexibility they provide, mobiles are designed for the individual user and behave like a communication island, independent and separate to the office phone system. On the other hand, the office desk phone provides all the productivity enhancing features such as reception services, access to the corporate directory, conferencing and call reporting, but is limited by its fixed nature.

Overview | Voice


Thousands of businesses trust Gamma for their critical voice services - we are one of the largest network carriers of fixed-line voice minutes in the UK. Having direct access to our own network means we can also react faster to your needs. As well as providing basic voice services, we're also the UK's market leader in SIP trunking and hosted services.

SIP Trunks

Our SIP trunking service connects your customers' businesses with our nationwide network, gives access to the PSTN and provides a more flexible and lower cost alternative to ISDN for inbound and outbound voice calls.

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Hosted Phone System

Horizon is a complete business communications service that provides an extensive range of fixed and mobile telephony capabilities via an easy-to-use web portal

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SIP Trunk Call Manager

SIP Trunk Call Manager is an innovative solution which encompasses all of the benefits of SIP Trunks combined with a unique web-based portal and App service that enables customers to take full control of all their inbound numbers, wherever they are, whenever they want.

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Our Inbound service provides online access to a full range of call routing, monitoring and management tools to empower your end-users and drive their customer service.

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