SIP Trunking

Make savings and add scalability to your business telephony

For business telephony, SIP Trunking is typically a better choice than ISDN.

SIP Trunking can reduce your call charges and ISDN rental bill, and lets you easily scale up capacity according to your needs.

Why choose hSo SIP Trunking?

Complete solution

We can combine SIP with leased lines, WANs and Internet access to deliver an integrated solution.


hSo has multiple connections to the phone network, and soft-switches in multiple data centres to ensure reliability.


If you currently use ISDN, SIP can cut your call costs and ISDN rental charges.

24/7 UK Support

Our telephony experts are always here for you.

Proven track record

hSo has been successfully delivering SIP for more than 10 years. We’re voice technology pioneers.

Call quality

Your SIP calls can be prioritised over your data traffic by hSo’s QoS-enabled MPLS network.

Additional Benefits

Range of telephony options

hSo’s voice range includes hosted PBXs, on-site PBXs, ISDN circuits and standard phone lines. We’ll find the best match for your organisation.


Resilience options

We know how important your phone service is to your business. That's why we offer enhanced resilience options that ensure you can still make and receive calls even if your main network connection goes down.

Smooth switch-over

We can use our substantial expertise to achieve a seamless switchover to SIP. For example, we can migrate most existing numbers over to SIP.


Attractive call rates

SIP calls are typically cheaper than ISDN ones. Unlike most of our competitors, we use multiple SIP wholesale providers, so we can give you the most attractive call rates, plus additional resilience.

hSo’s guide to SIP Trunking

Get the key facts on:

  • Whether SIP Trunking is relevant to your business
  • How SIP can save you money
  • Making SIP more reliable than your ISDN lines.
Brompton’s phone calls travel over its network connection, eliminating the need for ISDN circuits, cutting call charges and boosting scalability.

Brompton Asset Management case study

Get in touch

 020 7847 4510

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