01225 800 800
01225 800 888

Replacing the need for a traditional phone line, SIP Trunks run over a broadband connection and offer added control and flexibility without compromising on security. Built for businesses with existing infrastructure, this is a future-proof solution to connect your PBX to the trunks for a fraction of the cost.

Business Benefits

Reduce your costs
Reduce your costs
Take advantage of the hugely reduced costs of VoIP calling, whilst keeping your existing systems.
Infinite Scaleability
Infinite Scaleability
Simply and efficiently increase your SIP Trunks on demand, growing your business without limitations.
Keep your current systems
Keep your current systems
There is no need to replace your current hardware or PBX, simply upgrade and enjoy the additional benefits of SIP Trunk

Competitive pricing

We design bespoke packages for businesses of every size. Operating our own resilient network, we can set up new accounts quickly and easily.

Bundle in local, national and international numbers, and combine with our connectivity services for extra cost savings.

Per channel
From: £4

/ per month

Local, national and international bundles available

Why Gradwell for SIP Trunking?

The SIP experts
The SIP experts
We operate and own our own network, so know everything there is to know about connectivity and trunking.
Relied on by thousands
Relied on by thousands
Thousands of UK SMEs rely on us for secure and cost-effective SIP trunks every single day.
SME Specialists
SME Specialists
As an SME ourselves, we know better than anyone how to build communications infrastructure for growing small businesses.
UK Team
UK Support and Development
Our entire team is based in Bath, from support, to development and account management.

Our SIP Trunk Products

SIP Trunks

Take advantage of our SIP Trunk service, built for demanding SMEs.

Microsoft Teams Direct Routing

Take another step towards unified communications. Connect your calls directly to Microsoft Teams using SIP Trunks.

High Volume SIP

Purpose-built for call centres and telemarketing with high call volume.

Talk to an expert

We will use your information to keep you informed about our latest news and products. You may unsubscribe at any time using the links at the bottom of our emails. For more information, see our Privacy Policy.

Used by thousands of UK SMEs

Our systems are trusted by 8,000+ businesses from across the country


How does high volume SIP differ from the normal SIP Trunks?
High-volume SIP Trunks run on a separate dedicated platform built for high volumes of traffic and CAPS. This allows you to use the volumes you want without any issues.
How long will porting my number take?
Porting numbers can take up to two weeks depending on how many you have! We will request it as soon as possible and inform you when your number has been ported.
How quickly can I scale up my SIP Trunk?  
Simply give our team a call on 01225 800800 and they will be able to get this sorted for you in minutes.
Is there a limit on how many phone numbers I can have? 
 Not at all! You can have as many as you like from as many locations as you want.
What makes Gradwell different?
Built in the UK, we have a team of over 20 developers who are constantly evolving and advancing our technologies. With a range of packages to suit your business needs, you can tailor our products and services to suit your business needs and demands.
Can Gradwell provide me an internet connection to run the SIP trunks over?
Gradwell has a wide range of connectivity options available that are suitable for running our SIP trunking services over. In just a few questions, our team will be able to advise which connectivity option is suitable for your business.

Get in touch with an expert today.