Voice and Collaborative Working

Microsoft Teams Voice

Enable users to make and receive calls within Microsoft Teams, it’s the flexible and cost-effective alternative to Microsoft Calling Plans.

Cloud PBX and Hosted UC

A Cloud PBX solution moves all your telephony supporting infrastructure to the cloud and provides users’ access to many more services than just calling.

SIP Trunking

Get a next generation access to the PSTN allowing inbound and outbound telephony for termination to a full range of national and international destinations.


Replaces traditional landline service using VoIP Technology to deliver voice call over the broadband network.

Inbound Numbers

Our Inbound Numbers solution is easy to use and can be managed from anywhere, on any device and with any number. You can improve your customer experience by including call management features such as interactive voice response, call queuing and voicemail to your number.

VoIP services for replacing PSTN and ISDN lines

Trustmarque can take ownership of your PSTN and ISDN services to deliver cost savings and aid in the smooth transition to IP Voice.

Broadband and connectivity

At Trustmarque, we supply a range of business grade connectivity options, from business broadband and SoGEA to dedicated ethernet access solutions.

Case study

Kent County Council transition to Microsoft Teams Direct Routing from Gamma and Trustmarque

Kent County Council was using both the online and on-premise versions of Skype for Business, with approximately 5,000 users on each platform. The solution was approaching end of life at the end of July 2021 the Council knew they would have to quickly migrate all existing users to an alternative telephony solution. A decision had already been taken to migrate to Cloud Telephony in order to experience the commercial and operational benefit of removing any on-premise equipment

Discover how Trustmarque’s Enterprise Connectivity team and Kent County Council migrated 10,000 users to a simplified Teams telephony solution: Read the full case study

Kent County

“Migrating 5,000 users quickly and seamlessly was no mean feat. But Gamma and Trustmarque worked so well together, we felt that we were in safe hands. The project was executed quickly and efficiently, our telephony solutions are now simplified, and we can operate within a fixed budget.”

Stuart Cockett, Interim Head of Kent Public Services Network


Telephony users supported across the UK


Users enabled for MS Teams Direct Routing

1/3 billion

Calls delivered for clients each year

Our voice and collaborative working partners

Our long-standing partnerships enable Trustmarque to deliver industry-leading solutions so we can help you maintain and grow a competitive edge within voice and connectivity. Our partners include Gamma Telecom, Microsoft, Geomant, Buzzeasy, Cirrus, Colt and Cisco.

Microsoft Gold Partner
Cisco Gold Partner

How Trustmarque’s solutions help

Our experts will work with you to develop and implement a strategy to help improve your business effectiveness and return on investment. We use the most innovative collaboration tools and technology solution providers available allowing us to offer unrivalled flexibility, deployment speed, intuitive adoption strategies and control of business intelligence.

Whatever your organisation’s long-term goal, whether it be voice enablement of Microsoft Teams or replacement of legacy telephone systems, Trustmarque is here to get the wheels in motion. Our long-standing partnerships give us access to industry-leading solutions meaning we can help your business maintain and grow a competitive edge.

During the project lifecycle, we will guide you from strategic planning through to design, implementation, management and support. We’ll ensure you minimise risk and get the most from your communication and collaboration tools.

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