Hosted PBX & SIP Trunks for Modern Business
SIP Trunks replace traditional phone lines with secure, resilient connections over broadband internet, seamlessly linking your business PBX to the PSTN while protecting your existing telephony investment.
What are SIP Trunks and how do they work?
SIP Trunks, designed to replace traditional phone lines, utilize broadband internet connections to seamlessly connect your business phone system (PBX) to the traditional phone network (PSTN), eliminating the need to replace your existing hardware.
SIP Trunks, or Session Initiation Protocol Trunks, are virtual connections that enable the transmission of voice and other unified communications services over the internet. They replace traditional telephone lines by using the internet to carry voice and data traffic, offering cost savings, scalability, and flexibility for businesses.
SIP trunking delivers better flexibility and cost efficiencies of up to 50% by simply connecting to the phone network via the internet. It may be more budget friendly, but it’s also incredibly reliable – ensuring your calls are never lost through line faults or power cuts. Traditional phone lines are being phased out in 2025, so SIP trunks are the ideal future proof option to protect your business.
Top Features & Benefits
Discover why SIP trunking is the natural evolution of business voice.
Cost Savings
Significantly reduce line rental and call costs, including long‑distance and international traffic.
One Point of Contact
Enjoy a single provider for connectivity, SIP trunks and support, simplifying management and billing.
Keep or Choose Numbers
Port your existing numbers or select new geographic and non‑geographic ranges as your business grows.
Scalability
Quickly add or remove channels as demand changes, without the delays of installing new lines.
Flexibility
Support voice, video and unified communications services over a single IP connection.
Improved Service Levels
Build resilient call routing with failover, overflow and remote working options for your teams.
Centralised Management
Bring multiple sites, offices and numbers together onto one SIP platform and portal.
Global Reach
Reach customers and teams worldwide with international numbering and global routing options.
Integration & QoS
Integrate with PBXs, contact centre platforms and collaboration tools with quality of service controls.
Future-Proofing
Be ready for the PSTN switch‑off with all‑IP voice services designed for modern networks.
Why SIP Trunks are Good for Business
SIP trunking gives organisations a more agile, resilient and cost‑effective way to handle their voice traffic. With the ability to scale channels on demand, route calls intelligently and support hybrid or fully remote workforces, it’s an ideal choice for growing businesses that want to modernise without replacing existing PBX investments.
Why buy SIP Trunks from us?
Cost‑Effective Solutions
We provide SIP Trunks with competitive pricing, allowing businesses to reduce telecommunication expenses without sacrificing quality or reliability.
Security and Compliance
Security is a priority. Our SIP services include robust protection, encryption options and policy controls to safeguard data and support compliance with industry regulations.
Advanced Features
Unlock advanced features such as call forwarding, voicemail‑to‑email, auto‑attendants and virtual numbers to power modern business communications.
Easy Management
Manage SIP channels through an easy‑to‑use centralised portal, making it simple to add capacity, view usage and make routing changes.
Exceptional Customer Support
Our UK‑based teams provide dedicated support for setup, maintenance and troubleshooting, ensuring you always have expert help when you need it.
Recommended by 3CX
As a 3CX preferred supplier with native integration and setup, we offer end‑to‑end solutions that pair 3CX with resilient SIP trunks, connectivity and hardware.
Specialist SIP Services
We offer a wide range of bespoke SIP products to meet your specific requirements, from Microsoft Teams integration to high‑volume call environments.
Direct Routing for Microsoft Teams
Use Microsoft Teams as your business phone system. Direct Routing connects Teams to the traditional phone network (PSTN), turning your internal collaboration tool into a complete unified communications platform with external calling.
Frequently Asked Questions
A SIP trunk is a virtual connection that uses the Session Initiation Protocol (SIP) to establish a voice or multimedia session over the internet. It allows businesses to make and receive calls over an IP network rather than traditional phone lines.
SIP trunks use the internet to transmit voice, video and other multimedia communications. They connect your PBX to the SIP provider's network, enabling communication with external parties using IP‑based networks and the traditional phone system.
Key benefits include cost savings (especially for long‑distance and international calls), scalability (easily adding or removing channels), flexibility (supporting voice, video and messaging) and improved disaster recovery, with calls rerouted quickly in case of issues.
You'll need an IP‑enabled PBX or a session border controller (SBC) to manage communication between your internal network and the SIP trunk provider, plus a reliable internet connection with enough bandwidth for your call volumes.
Yes. In most cases you can port your existing numbers to SIP trunks so you keep the same contact details while moving to an IP‑based service.
SIP trunking can be highly secure when implemented with encryption, authentication and the right firewall and SBC controls. Working with a reputable SIP trunk provider helps safeguard your communications end‑to‑end.
Crucial Terms: Pricing & Policy
At CloudXVoice, we’re your go‑to partner for cutting‑edge technology solutions in the UK. Our services cover CCTV, Security Systems, Broadband, Telecom Connectivity, and more. With a reputation for reliability and innovation, we offer monthly billing per user, excluding VAT, with a 12‑month commitment. Our promotions last 6 or 12 months, returning to standard pricing thereafter. Unlimited calling is available, terms apply. Visit cloudxvoice.co.uk for details. Please note, images on our site may feature CloudXVoice CCTV Cameras and other equipment features under development.
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