Reliable, High-Performance SIP Trunks
Powerful, cost-effective, and 3CX-certified SIP Trunks—delivering clear and reliable call quality for UK businesses.
What are SIP Trunks and how do they work?
Designed to replace traditional phone lines, SIP Trunks use broadband internet connections to connect your business phone system (PBX) to the traditional phone network (PSTN) without needing to replace your existing hardware.
With the PSTN network due to be switched off by 2025, now is an ideal time to experience the benefits of connecting your business phone system to the internet.
Benefits of SIP Trunks
Cost effective
Lower installation fees and monthly costs, including DID provisioning and call charges for both national and international numbers.
Improved service levels
Ensure that customers can reach you, wherever they (and you) are at a lower cost and via a quality connection.
Flexibility
Change location, expand into new markets and forward calls at a moment’s notice without any business disruption.
Easy management
Instantly provision additional resource as needed, on a permanent or temporary basis.
Flexible numbering
Regardless of physical location – even if this changes – present local, non-geographical or international numbers as needed.
Easy to scale
SIP Trunks are a cost-effective way to easily scale up or down depending on your business requirements.
Why Choose Gradwell SIP Trunks?
We are the UK’s SIP pioneers and we take pride in the resilience of our network. We have a team of over 20 developers who are constantly evolving and advancing our technologies. That’s why we’re trusted by hundreds of organisations for business-critical SIP services. See what else makes Gradwell stand out from the crowd…
Our own network
We operate and optimise our own network, security and systems directly from our HQ.
Cloud based
All of our SIP Trunks operate in the cloud and can be setup in minutes.
Resilient and secure
We are ISO 27001 certified and our Network Operations Centre monitors our systems at all times.
Trusted by thousands
Thousands of UK businesses rely on us for secure and cost effective SIP Trunks every single day.
Recommended by 3CX
We are one of only a handful of suppliers to have 3CX preferred status, with a native 3CX integration and set-up.
Easy management
Manage your SIP channels through our easy-to-use centralised portal.
Specialist SIP services
- Direct Routing
- Specialist 3CX SIP
- High Volume
Use Microsoft Teams as your business phone system. Direct Routing is the process of connecting Microsoft Teams to the traditional phone network, or PSTN. It is an increasingly popular way to turn Teams from a powerful internal communications tool to a full-scale unified communications platform.
We are a market-leading 3CX solutions provider – from onboarding and setup to support and maintenance, we help businesses feel secure when purchasing the 3CX system. Our end-to-end packages all include UK-based support, SIP trunks, connectivity and hardware. Deployed in a highly resilient cloud to guarantee service levels – not included in most suppliers’ standard offering.
We have designed our own high-volume SIP Trunks specifically for customers needing high call-per-second and high channel capacity. Integrating directly with your existing PBX, our high-volume SIP Trunks allows you to take advantage of the cloud-based solutions, without replacing your existing equipment.
Frequently asked questions
What are SIP Trunks?
Designed to replace traditional phone lines, SIP trunks use broadband internet connections to connect your business phone system (PBX) to the traditional phone network (PSTN) without needing to replace your existing hardware. With the PSTN network due to be switched off by 2025, now is an ideal time to experience the benefits of connecting your business phone system to the internet.
What makes Gradwell SIP different?
Built in the UK, we have a team of over 25 developers who are constantly evolving and advancing our SIP infrastructure. Our SIP trunks are performance tested with all major PBX vendors, deployed in a highly resilient cloud environment (AWS) across multiple carriers and come with a range of flexible packages including PAYG and bundle options.
What is a SIP Channel?
A SIP channel is the capability to support incoming and outgoing calls. Every SIP trunk contains a number of channels, which are virtual versions of telephone lines. The number of channels you need depends on how many concurrent calls your business makes.
What’s the difference between SIP and VoIP?
VoIP or Voice Over Internet Protocol makes and receives phone calls over the internet or internal networks. SIP is an application layer protocol used to make, manage and terminate multimedia sessions, including voice, video and messaging. While SIP is an initiation in its own right, it is mainly used to support IP technology, like VoIP calls.
What requirements do I need for a SIP Trunk?
The basic requirement for SIP trunks is an internet connection, with good bandwidth and speed. This is determined by the number of calls you expect to be making and other web applications. You also need an IP PBX that is compatible with the SIP protocol required. If you do not have this, you may require a SIP card or license installation.
How do I set up a SIP Trunk and how much does it cost?
Setting up SIP is easy. Costs can vary depending on your specific requirements and usage. Contact us today and we’ll set up everything for you and give you a competitive price.
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