Scalability To Grow With You
Free Calls Across Our SIP Trunks
Use Any Geographical Number
Multiple Options Of SIP Trunk Disaster Recovery
All Modern PBX Supported
Supported By SIP Designed Data Connections
Business Grade SIP Trunks Overview
Take advantage of our low cost SIP Trunk line rental and call charges which are compatible with all types of telephone systems that can use SIP Trunks.
Our SIP trunks allow you to relocate your business without the call diversion costs associated with changing to a new geographic number. This not only provides continuity of service, yet removes the costs associated with changing numbers on literature, stationery, business listings etc. Equally we can provide any 01/02 geographic number into your SIP account, providing your business with a presence anywhere across the UK.
Continuity Of Service
Combining our SIP trunks with our Inbound platform will offer your business a secondary level of disaster recovery. DR can be added within the SIP setup to enable an instant divert to a secondary destination if required.
Future Proof And Rationalisation
With BT withdrawing ISDN services in 2025, SIP trunks is a future proof alternative to any ISDN30e or ISDN2e solution. For businesses with multiple sites SIP trunks provides ISDN rationalisation, which is a great way to reduce the number of phone systems requiring maintenance.
Free UK Calls And Fraud Prevention
Our SIP trunking service provides free call termination to UK fixed destinations, including 01, 02 and 03 number ranges. In addition, SIP provides free calls between connected sites, including international locations. We also provide fraud protection and alerting at no cost with all our SIP trunks.
Assured Voice Calls
Assured IP is a voice only broadband connection created for SIP trunks. These connections are 1:1 contended, have QoS, and prioritise voice traffic. Our SLA includes a target service availability of 99.95% from the core network.
Converged Broadband is a voice and data circuit, allowing SIP trunks and web browsing on a single connection. They are provided with QoS using the Cisco 800 series routers, and are backed by a performance SLA, ensuring clarity in voice on our SIP trunks.
Business Grade SIP Trunks Benefits
Free calls between SIP sites
Low SIP trunk rental per month inclusive of 01, 02 & 03 calls
Free Mobile Calls
2,000 minutes of free mobile calls per SIP trunk
Fully scalable on a per SIP channel basis, unlike ISDN
Low Initial Cost
Minimum order is only 2 SIP Trunks/Lines
Any UK Range
Flexible number ranges on our SIP service
Easy to order and provision to your Equipment and integration strengths
Any Internet Technology
SIP is available over LLU/ADSL, EFM or Ethernet
Offers emergency services support
Voice Internet Circuits
SIP designed data connections offering QoS, including Assured & Converged
Frequently Asked Questions
Discover the answers to our most popular questions below
SIP stands for session Initiation protocol which is the protocol that controls setting up the call and tearing it back down again.
A SIP trunk is a virtual telephony line that connects your office to the outside world using a data connection instead of an ISDN or analogue phone line. SIP trunks carry your voice calls like an ISDN circuit would, generally at a lower cost. SIP calls between two SIP enabled sites are zero cost as the call remains on-net.
A SIP Trunk is carried across your existing data network. This removes the requirement to have expensive BT Openreach line rentals. SIP trunks are more flexible than normal PSTN lines. They allow you to present multiple numbers to your customers, and the number your business uses day-to-day is not subject to your location – it can be any number.
Whilst you can run SIP Trunks on any data connection we recommend using one of our designed data circuits, either assured IP, converged or Ethernet. SIP calls require bandwidth, and if you do not have sufficient bandwidth on your existing data circuit it is likely you will experience disconnected calls and jitter.
Providing you choose the right partner, YES. SIP calls can become problematic if:
- The data connection cannot support the number of concurrent calls
- The SIP network is not reliable with the necessary failover equipment
- The end user equipment is not up to date to support your SIP trunks
Generally the answer would be YES. SIP trunks are cheaper than ISDN30e and ISDN2e line rental, and call costs are lower when utilising SIP trunks, including zero cost site-to-site calls. However what is sometimes overlooked is the internet connectivity to deliver your SIP calls. As mentioned in the SIP reliability question, to try and push SIP calls across a low-end data connection could have a disastrous impact on your business.
If your phone system is new, it is likely you will have the capabilities to connect SIP trunks without too much fuss or cost. What you may need is an additional SIP card or licenses which you will need to obtain from your phone system supplier or Maintenance Company.
If your phone system cannot support SIP then now may be the time to look at a hosted solution. We have 1000’s of users currently enjoying the benefits of Horizon today.
In most cases, YES. Geographic number porting is quite simple and painless. We can port your geographic number from most Tier 1 carrier networks. 95% of the time customers port their geographic number from ISDN or analogue BT Openreach lines to our SIP trunking solution.
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