Agile SIP Trunking
Supporting Microsoft Teams, Webex, 3CX and traditional telephony environments like your PBX.
Why Choose Callroute SIP Trunking?
Using Callroute SIP Trunking, you can connect your phone numbers to the environment of your choice in minutes.
You won’t have to worry about porting your numbers ever again.
Simplify migrations with our self-service portal.
Enjoy 99.99% availability with our robust network.
Connect Teams, Webex, 3CX, and your PBX.
Easily map numbers across different services.
Hybrid SIP Trunk Pricing
Hybrid SIP Trunk - PAYG
£5.95 monthly per SIP channel
Add onto any plan!
Ideal for businesses that don’t make many outbound calls
- Minimum 5 channels
- Pay-as-you-go outbound calling minutes
- No set up fees (excludes number porting)
- Access to detailed reporting
- Access to self serve portal to facilitate migrations to Teams or other UCaaS platforms
- Add call recording for an additional £4.95 a channel
- Add floating minute bundles - refer to FAQs for pricing
£1 per phone number monthly rental applies.
Hybrid SIP Trunk - 300
£9.95 monthly per SIP channel
Add onto any plan!
Everything you need to enable hybrid telephony for your business.
- Minimum 5 channels
- 300 domestic mins (01, 02, 03 and mobiles) per channel inclusive
- No set up fees (excludes number porting)
- Access to detailed reporting
- Access to self serve portal to facilitate migrations to Teams or other UCaaS platforms
- Add call recording for an additional £4.95 a channel
£1 per phone number monthly rental applies.
SIP Trunk Features
Highly available SIP trunk solutions for organizations of any size.
Flexible pricing
Pay as you go month-to-month or fixed annual commitment
Inclusive minutes
Flexible options around inclusive minutes or simply pay for the calls you make
Auto scaling
Temporarily burst beyond licensed capacity (conditions apply)
Secure Calling
Ensure your conversations are secure with encryption
Reporting
Detailed call reports enable you to track your usage
Call recording
Record PSTN calls for customer success training & compliance (optional)
Integration
Spread your SIP trunk capacity across cloud and on-premise telephony
Availability
99.99% availability built-in with multi-layered resiliency
SIP Trunking FAQs
What is SIP Trunking?
SIP Trunking replaces the traditional phone line (ISDN or analogue) and typically uses the internet to connect your on-premises phone system (E.G. PBX) to the PSTN.
SIP trunking is widely available from many vendors. What differentiates Callroute’s SIP trunking service from others?
It’s true that SIP trunking is a widely available service, but Callroute goes beyond simply providing connectivity. We make SIP trunking a strategic enabler for digital transformation rather than a commodity.
No set-up fees and flexible contracts: Unlike many vendors, we don’t lock customers into long-term commitments or burden them with upfront costs. Our contract terms can be as short as a 30-day rolling agreement, giving you maximum flexibility.
Seamless migration capabilities: One of our biggest differentiators is how we position the Callroute SIP trunk as more than just a voice pipe. Once we are in the calling path, our platform makes it simple to migrate services away from legacy PBXs towards modern cloud calling solutions such as Microsoft Teams Phone or Webex Calling.
Click-to-migrate number management: Through the Callroute portal, customers can move phone numbers from one service (e.g., SIP trunk) to another (e.g., Teams) at the click of a button. This eliminates the complexity of number porting projects and makes transformation smooth, low-risk, and fast.
Pooled channel capacity across sites: Unlike many providers who allocate fixed channels per trunk, Callroute allows capacity to be pooled. This means you can deploy SIP trunks to multiple sites while sharing overall capacity, ensuring more efficient utilisation and reduced cost.
By combining flexible commercial terms, simplified migration, and innovative capacity management, Callroute elevates SIP trunking from a commodity to a strategic tool for business communications.
By combining flexibility, cost transparency, and powerful migration tools, Callroute transforms SIP trunking from a commodity into a catalyst for cloud adoption.
What is the UK PSTN switch off?
In 2017 Openreach announced that they are turning off the old analogue based PSTN in 2025. PSTN telephone lines include ISDN which many businesses have, these could be ISDN2 (BRI) or ISDN30 (PRI). Additional information can be found on BT’s website.
If I pay per user for Callroute Direct Routing, do I also need to pay for SIP trunking?
No. The SIP channel pricing includes the per-user fee. However, if you still have your PBX (or similar) connected via Callroute, you are still required to pay for the associated channel capacity towards that environment.
Are there any setup costs for a SIP Trunk?
There are no set-up costs for SIP Trunks as our platform is self-service. However, there may be costs associated with number porting (if required).
How many phone numbers can I get with a SIP Trunk?
There is no maximum number of phone numbers. Port or buy as many phone numbers as you need.
How many phone lines do I get with a SIP Trunk?
There is no maximum number of phone lines (channels) per SIP Trunk, you can have as many as you like. There is, however, a minimum count of 5 channels per deployment.
How do I migrate numbers from my PBX to Teams, or other supported services in Callroute?
All numbers and associated assignments will be visible in the callroute.io portal. Numbers can be remapped individually or in bulk. Changes take 1 to 2 minutes to take effect.
Can I see how many channels I am using?
Yes, this can be viewed in the reporting section of the Callroute.io portal.
Get Started Today
Speak with our experts to discover how Callroute SIP Trunking can transform your telephony.
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