SIP trunking provides the connection between in-house PBX systems and the internet to allow you to make calls over the internet where you have a dedicated internet connection through broadband or leased line. SIP trunking gives businesses an alternative to ISDN lines which are being phased out by 2025 as well as offering lower costs and flexibility. Below we have explored what the leading providers offer.
The table below gives a quick price comparison of the top UK providers for SIP trunking.
| Company | Price from monthly |
|---|---|
| BT | £13 |
| TalkTalk | £120 |
| Virgin Media | Not stated |
| Zen | £30 |
| KCOM | Not stated |
| O2 | No monthly charge |
| Vodafone | Not stated |
| Stream Networks | £5.50 |
| Ai Networks | Not stated |
| hSo | Not stated |
| Telecoms World | £9.50 |
| Boxx Internet | Not stated |
| Andrews & Arnold | £1.20 |
| Cerberus Networks | Not stated |
| FluidOne | Not stated |
| Gradwell | £4 |
| Southern Communications | Not stated |
| Spitfire | £4 |
| Structured Communications | Not stated |
| Best 4 Business Communications | Not stated |
| Sipgate | £4.95 |
| Focus Group | £5.99 |
| Pioneer Global Services | Not stated |
| Talking Technology | Not stated |
* The facts and figures included here come from each company’s website and were accurate at the time of writing (January 2022) but may have since changed. Also, please keep in mind these may not be apples to apples comparisons as each provider offers different solutions. This guide should be used as a starting off point for more research on your part.
Below we profile each of the companies’ services and features in a bit more detail.
Note companies are ranked in no particular order and this no way indicates one solution is better than another.
1. BT
Some of the features and benefits of BT’s SIP trunking.
- BT Cloud Voice SIP connects phone systems to the internet
- Spend less on business calls
- More flexible services
- Greater control of your calls
- Prioritisation of your calls over the internet
- Built-in resilience
- Simple transfer
- Great for remote working
- Requires an internet connection with enough bandwidth which they can supply
- UK-based support and local engineers
2. TalkTalk
Some of the features and benefits of TalkTalk’s SIP trunking.
- Business phone networks delivered over the internet
- Greater flexibility
- Can offer financial savings on either PAYG or inclusive call bundles
- Highly resilient and offers multiple disaster recovery options
- Delivered over Ethernet data circuits
- Prioritises your calls over your data traffic
- Superior call quality
- Combine your voice and connectivity
- Scalable solutions from 1 trunk upwards
- 24/7 UK-based customer support
3. Virgin Media
Some of the features and benefits of Virgin Media’s SIP trunking.
- Uses data networks for voice communication
- Optimised secure data connection
- Single connection for data and voice
- Can plug straight into your existing phone system
- Maximise your data network
- Scalable solution
- Includes a range of call handling functionality
- Future-proofed solution
- Suited to medium to large businesses and multiple sites
- 24/7 customer support
4. Zen
Some of the features and benefits of Zen’s SIP trunking.
- Replaces or works alongside traditional analogue/ISDN lines
- Offers increased flexibility
- Opportunity to make cost savings
- Choice of geographical numbers
- Provides business continuity of automatic re-routing
- Delivers fraud protection
- Highly scalable solution to quickly add capacity
- Only pay for what you use
- Good for remote workers and multiple offices
- Only available to their connectivity customers
5. KCOM
Some of the features and benefits of KCOM’s SIP trunking.
- Highly flexible voice service
- Internet-based service
- Offers significantly lower costs than traditional ISDN lines
- Will recommend a solution to meet your needs
- Consistent quality
- Provides a business continuity solution
- Full scalability
- Seamless continuity
- Internet requirements vary depending on the bandwidth
- UK-based customer support
6. O2
Some of the features and benefits of O2’s SIP trunking.
- Flexible voice and data connectivity
- Can be easily adapted
- Resilient network
- Can make cost savings compared to ISDN
- Offer three simple packages
- PAYG and inclusive minute packages
- Scalable solutions
- Combine fixed lines, mobile and data
- Will help you select the best solution for your needs
- 24/7 customer support
7. Vodafone
Some of the features and benefits of Vodafone’s SIP trunking.
- Integrated service for voice and data
- Flexible solutions
- Offers tailored support
- Reliable service
- Offers value for money with cheaper solutions
- Secure IP connection
- Provides greater control
- Offers two options
- Caters for businesses of all sizes
- Claims to deliver superior customer service and support
8. Stream Networks
Some of the features and benefits of Stream Networks’ SIP trunking.
- Connecting businesses with voice solutions
- Reduced telephony costs up to 50%
- Unified communication systems
- Lower call rates and line rental savings
- Inclusive UK calls
- Fast setup
- Choice of 2 packages
- 12 or 36-month contract lengths
- Operate their own networks
- Has a minimum of 2 SIP trunks
9. Ai Networks
Some of the features and benefits of Ai Networks’ SIP trunking.
- Combined voice and data service
- Simple ISDN alternative
- Cost-effective and competitive call costs
- Connections available on a variety of line types including ADSL, EFM, FTTC leased line and dedicated fibre
- Can be combined with their CloudPBX system
- Offers a range of business-friendly features
- Number porting available
- Designed to carry a variety of media including voice, data and video
- Scalable solutions
- 24/7 monitoring and UK-based support teams
10. hSo
Some of the features and benefits of hSo’s SIP trunking.
- Offers complete integrated solutions
- Combines SIP with leased lines, WANs and internet access
- Resilient network
- Can make significant savings
- Offers a range of telephony options
- Prioritise calls over data traffic
- Seamless switchover
- Uses multiple SIP wholesalers to offer attractive call rates
- Scalable solutions
- 24/7 UK-based customer support
11. Telecoms World
Some of the features and benefits of Telecoms World’s SIP trunking.
- SIP trunking that is compatible with all leading PBX brands
- Reduces the costs of inbound and outbound calls
- Flexible and resilient network
- High-definition calls
- Free office to office calls
- They work with some of the leading PBX vendors
- Save up to 70% on line rental
- Scalable solutions
- Built-in business continuity
- Highly rated on Trustpilot
12. Boxx Internet
Some of the features and benefits of Boxx Internet’s SIP trunking.
- Offers onsite PBX and SIP
- Flexible alternative to ISDN
- Cost-effective solution
- Compatible with all leading PBX brands
- Better call quality through IP telephony
- Improved call handling
- Provides business continuity in the event of a disaster or emergency
- Future-ready for when ISDN lines get shutdown
- Call management solutions to arm your business with the tools you need
- Highly rated on Trustpilot
13. Andrews & Arnold
Some of the features and benefits of Andrews & Arnold’s SIP trunking.
- Flexible internet call solutions
- Inbound and outbound calls for larger companies
- Replaces ageing and expensive ISDN lines
- No limit on the number of channels
- Low-cost calls and monthly charges
- No cost for internal calls
- Low setup costs
- Easily scalable
- Not restricted to physical locations
- UK-based technical support teams
14. Cerberus Networks
Some of the features and benefits of Cerberus Network’s SIP trunking.
- Next-generation telecoms designed for businesses
- Cost-effective and competitive voice solutions
- Increased functionality and scalable
- No up-front investment on system hardware
- Choice of handsets
- Can use existing hardware if supported
- Offers number flexibility
- Quick and easy setup
- Provides business continuity
15. FluidOne
Some of the features and benefits of FluidOne’s SIP trunking.
- Connectivity solution for phones over the internet
- Great for controlling multimedia communication sessions
- Can be used for voice, video, instant messaging, virtual whiteboards, file and desktop
- Cost-effective with competitive tariffs
- Offers bundles of landline and mobile minutes
- Cheaper replacement for ISDN lines
- Tailored packages that are scalable
- Resilient with business continuity built-in
- Dedicated service delivery team that will get you set up in 2-4 weeks
- 24/7 customer support
16. Gradwell
Some of the features and benefits of Gradwell’s SIP trunking.
- Replaces the need for traditional phone lines
- Connects your existing PBX to the internet
- Added control and flexibility
- Secure service
- Can reduce your costs
- Scalable solution
- Competitive pricing
- Bespoke solutions which you can bundle in local, national and international numbers
- Can combine it with the connectivity services
- UK-based customer support
17. Southern Communications
Some of the features and benefits of Southern Communications’ SIP trunking.
- Offers a flexible SIP trunking solution
- Can offer a reduction in costs
- Suitable for a single user to a large call centre
- Scalable solutions
- Resilient with back-up and disaster recovery
- Combine voice and data connectivity
- Can use desk phones and mobile devices
- Requires a dedicated broadband or leased line
- Offers connectivity solutions to complement SIP trunks
- UK-based customer service
Southern Communications website
18. Spitfire
Some of the features and benefits of Spitfire’s SIP trunking.
- Install their own SIP trunks
- Lower rental and call costs
- Seamlessly works with most phone systems
- Provides assured call quality
- Highly scalable solution with fast deployment of extra capacity
- Resilient service
- Can be utilised for voice and data
- Allows you to consolidate line usage across sites
- Can include SIP gateways to increase compatibility
- Provides a dedicated account manager
19. Structured Communications
Some of the features and benefits of Structured Communications’ SIP trunking.
- Offers SIP trunks and channels
- Flexible phones lines for internet calls
- Lower costs for line rental and calls
- Increased flexibility to add channels and users
- Internal calls are free
- Portable with number flexibility
- HD quality calls
- Offers multi-level resilience
- Highly rated on Trustpilot
- 24/7 network monitoring
Structured Communications website
20. Best 4 Business Communications
Some of the features and benefits of Best 4 Business Communications’ SIP trunking.
- Internet service for voice and streaming media
- Bespoke solutions
- Lower line rental and call charges
- Flexible system
- Built-in disaster recovery
- Scalable solution with quick deployment
- Portable numbers
- Future-proofed for the ISDN switch off
- Can facilitate unified communications
- 24/7 support and monitoring
Best 4 Business Communications website
21. Sipgate
Some of the features and benefits of Sipgate’s SIP trunking.
- Connects VoIP PBX to the telephone network
- Premium voice quality
- No setup fees
- Highly flexible solution
- Competitive outbound call rates and no inbound call charges
- Can combine it with their hosted PBX system
- Helps combine services across locations
- Assists with disaster recovery
- Can be upgraded or downgraded at any time
- Provides 24/7 network monitoring
22. Focus Group
Some of the features and benefits of Focus Group’s SIP trunking.
- Cost-effective alternative to ISDN lines
- Increased flexibility
- Lower costs with free internal calls
- Compatible with all leading IP PBX brands
- Includes business continuity support
- Competitive call charges
- No connection fee or call connection costs
- Scale-up and down whenever you need to
- Suitable for businesses of all sizes
- Award-winning provider
23. Pioneer Global Services
Some of the features and benefits of Pioneer Global Services’ SIP trunking.
- Offers the benefits and advantages of VoIP services
- Utilises your existing telecoms setup
- Replaces ageing ISDN
- More affordable call charges than traditional phone lines
- Incorporates home workers
- Number porting
- Scalable solution
- No area restrictions on numbers
- No expensive call forwarding services
- UK-based support
Pioneer Global Services website
24. Talking Technology
Some of the features and benefits of Talking Technology’s SIP trunking.
- Flexible alternative to ISDN lines
- Lower cost solution
- Quicker installation
- Robust business continuity built-in
- Free internal calls
- Offers a host of features
- Scale-up and down when needed
- Compatible with Skype for Business
- They work with a range of PBX vendors
- Caters for a range of business sizes