› connectivity & telecoms
leased lines & wan
Leased LinesDedicated, uncontended fibreDedicated Internet AccessGuaranteed, SLA-backedFTTP & Full FibreUltrafast full fibreSD-WANIntelligent multi-site WANMulti-Site ConnectivityOne secure networkBackup ConnectivityAutomatic 4G/5G failovermobile
Business MobilesO2, Vodafone & EE airtimeSIM Only DealsFlexible 30-day & 24-monthMobile Broadband4G / 5G data-only SIMsStatic IP SIMsFixed IP for IoT & failovertelecoms
Cloud Hosted PBXVoIP phone system, powered by VoipingerSIP TrunkingConnect your PBX, cut call costsMicrosoft Teams PhoneCalling inside TeamsBusiness Phone NumbersLocal numbers in 145+ countriesCRM Integration250+ apps, click-to-dialAI Receptionist24/7 AI voice agentAI Contact CenterAI voice & chat at scale› cyber security
Wifinger
Our own guest Wi-Fi platform: a branded login page on the access points you already have, plus consent, analytics and marketing — designed, installed and managed by us.
Explore guest Wi-Fi› design · deploy · support
› surveillance & data infrastructure
Business connectivity you can rely on
Fibre broadband, leased lines, business mobile and cloud telephony — one partner for every connection.
Always-on connectivity and calling
From ultrafast full fibre to VoIP and Teams Phone, we keep your business connected and talking — with SLAs that mean it.
› what you get
- Full fibre (FTTP) & leased lines
- VoIP & Microsoft Teams Phone
- Business mobile on Vodafone & O2
› what's included
One partner for business internet, mobile & phone systems
Most London businesses juggle a broadband provider, a mobile network and a phone-system vendor — then chase three help desks when something breaks. CLI Secure brings connectivity and telecoms under one roof, so your internet, business mobile and cloud telephony are designed, installed and supported by a single accountable UK team. Explore each service below.
Business Internet & Leased Lines
Dedicated, SLA-backed connectivity that keeps every site online — from ultrafast full fibre and uncontended leased lines to intelligent SD-WAN and automatic 4G/5G failover.
Business Mobile & SIMs
Flexible airtime and data on O2, Vodafone and EE — from single SIM-only plans and mobile broadband to shared data pools and static-IP SIMs for IoT and failover.
Cloud Telephony & VoIP
Modern business phone systems — cloud-hosted PBX, Microsoft Teams calling, international phone numbers, CRM click-to-dial and 24/7 AI voice agents.
Why businesses choose CLI Secure
Ultrafast fibre
Symmetrical, future-proof connectivity.
Cloud telephony
VoIP and Teams Phone that scale with you.
Business mobile
Flexible airtime and SIM-only deals.
Guaranteed SLAs
Dedicated bandwidth with real uptime promises.
› how we deliver
A proven, low-risk process
Assess
We check availability and your bandwidth needs.
Quote
The right circuit and telephony plan for your budget.
Install
Provisioning and porting managed end-to-end.
Support
Proactive monitoring and rapid fault resolution.
› faq
Questions, answered
› let's talk
Ready to hand off the IT headaches?
Leave your details and a London-based engineer will call you back — usually within one business hour. No sales scripts, no obligation.
Or explore Managed IT →