Colt
London carrier offering enterprise SIP trunking tested with Genesys, Webex, Talkdesk and Microsoft Teams
Quick Overview
| Company | Colt Technology Services Group Limited |
|---|---|
| Category | SIP Trunking and Virtual Number Providers |
| Headquarters | London, United Kingdom |
| Founded | Not stated |
| EU Presence | Yes - United Kingdom (UK) |
| Data Location | Not stated on the pages checked |
| Open Source | No |
| GDPR Compliant | Yes |
| Self-Hosting | No |
| Main Features | SIP Trunking, SIP on Demand, number porting, local numbering, SRTP and TLS voice security, disaster recovery option, Colt Online management |
| Pricing | On request |
| Best For | Multinational enterprises consolidating voice suppliers |
| Replaces | Telnyx, Twilio Elastic SIP Trunking |
Detailed Review
Colt's website terms name Colt Technology Services Group Limited, registered number 03232904, with its address at Colt House in London. A separate page lists the wider Colt group of companies.
Its SIP Trunking page is written for large organisations, and the wholesale trunk product sits on a separate page for carriers and service providers.
Platforms it is tested against
The product page names Genesys Cloud, Cisco Webex, Talkdesk, Twilio Flex, Avaya Experience Platform and NICE CXone as interoperable contact-centre systems, and Microsoft Teams and Zoom among compatible UC platforms.
That list tells a buyer whether an existing stack is already covered without a custom integration project.
Security and resilience
Colt describes voice security with SRTP and TLS, geo-redundant architecture with automatic failover and a 99.999% uptime figure. A disaster recovery upgrade lets customers invoke and revoke services through Colt Online.
The company also says its trunking handles seven billion minutes a year and that it serves more than 3,500 customers in 29 countries, all self-reported.
Numbers and regulation
SIP on Demand supports requesting number porting or extra numbers online, and the page lists emergency call routing, lawful compliance and data retention under its regulatory features.
Number retention and acquisition across several countries is the main draw for multinational voice consolidation.
Limitations to Consider
No prices are shown, and the product page routes buyers to a contact form and datasheets. The company is built for enterprise contracts, so a ten-person office would find easybell or sipgate simpler. Which Colt group entity signs the contract in each country was not verified; the website terms name the UK parent only.
Who Should Use Colt
Large or multinational organisations that want one carrier across several countries and need compatibility with a contact-centre platform.
Pros and Cons
Pros
- UK entity named in the website terms
- Interoperability list with major contact-centre platforms
- SRTP and TLS voice security
- Number porting and local numbering in multiple countries
- Disaster recovery option
Cons
- No published prices
- Enterprise sales process
- Contracting entity per country not verified
- Wholesale trunking is a separate product
Alternatives to Colt
Other European sip trunking and virtual number providers worth comparing before you decide:
Simwood
United Kingdom · Bristol carrier that owns its voice network and exposes trunks through a portal and API
DIDWW
Ireland · Dublin-contracted wholesale supplier of SIP trunks and numbers with published per-minute rates
easybell
Germany · Berlin provider with trunk plans from two to 1,000 channels and no minimum term
sipgate
Germany · Duesseldorf provider connecting Asterisk, 3CX or Starface systems to the German network
See all European sip trunking and virtual number providers or compare them directly against Telnyx on our alternatives page.
Frequently Asked Questions
Colt Technology Services Group Limited, registered number 03232904, with its address at Colt House, 20 Great Eastern Street, London.
Its product page names Microsoft Teams and Zoom among compatible UC platforms.
No. The product page offers a contact form and datasheets instead.