voice /sip trunking

SIP Trunking for business

A flexible, cost-effective way to run your business phone system over your internet connection. Reduce costs, increase flexibility and keep your teams connected – wherever they work.

Why choose SIP Trunking for your business phone system?

Cut communication costs

Lower call charges, free site-to-site calling and the ability to consolidate services over a single connection.

Scale your service

Add or remove channels so you’re always ready for peaks in demand.

Built-in resilience

Automatic call re-routing keeps your business reachable in any situation.

Expert UK-based support

Get guidance from specialists who understand voice, networks and the needs of growing businesses.

ZEN CLOUD

SIP Trunking at a glance

SIP Trunking lets you run your business phone system over your internet connection rather than traditional copper lines. If you already have a PBX you want to keep – or you’re preparing for the PSTN switch-off – SIP gives you a modern, flexible and cost-effective way to stay connected.

It’s ideal for businesses that want to make use of existing equipment, support multiple sites or enable hybrid working without adding complexity.

SIP Trunking brings together cost savings, flexibility and reliability. You can scale channels as demand changes, support multiple locations, keep your existing numbers and maintain clear, consistent call quality. It’s a simple way to modernise your voice setup without replacing the equipment you rely on.

Flexible and scalable voice

Add or remove channels as you need them, without long lead times or engineer visits.

Reliable call quality

Your calls run over Zen’s highly resilient network, delivering clear, dependable performance.

Business continuity built-in

If your office goes offline, calls automatically divert to another site, device or team.

Cost-efficient communication

Lower rental, lower ongoing charges and free calls between sites.

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How SIP Trunking works

SIP Trunking replaces traditional PSTN and ISDN lines with virtual channels that run over your internet connection. If you have a compatible IP PBX, you can continue using your existing phone system – but with far greater flexibility and lower running costs.

Because SIP sits on top of your connectivity, it’s quick to scale and simple to manage, with built-in resilience for hybrid and multi-site teams.

Who SIP Trunking is for

Businesses with an existing PBX they want to retain
Organisations preparing for the PSTN switch-off
Multi-site companies that need to route calls intelligently
Contact centres and teams with fluctuating call volumes
Hybrid or remote teams that need consistent voice services
Businesses wanting UK-wide number flexibility

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Customer Success Story

Lindab

When this UK leader needed a more resilient and flexible communications setup, they turned to Zen for a solution that keeps every site connected.

Read the full story

Simply fill in the form, and our team will be in touch to discuss your needs.

GET IN TOUCH

Talk to a Zen voice specialist

If you’re considering SIP Trunking, or want help choosing the right voice solution, our experts are here to guide you.

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