› connectivity & telecoms
leased lines & wan
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Business Leased Lines in London
A dedicated, uncontended fibre connection built for your business alone — symmetric speeds, a guaranteed SLA and rock-solid uptime. We source, install and manage it end to end.
› get a quote
Check pricing for your postcode
Tell us the speed and location — we compare every major UK carrier for your exact address and send a tailored, no-obligation quote, usually within one working day.
- Carrier-neutral — we compare the whole market
- No obligation and no sales pressure
- Fully managed install and support
Step 1 of 3
What speed do you need?
Not sure? Pick “Not sure yet” and we'll advise based on your team and apps.
Internet your business can actually rely on
A leased line is a dedicated, private fibre connection between your premises and the internet — not shared with anyone else. Unlike ordinary broadband, the bandwidth you buy is the bandwidth you get, in both directions, at every hour of the day. That means clean video calls, fast cloud apps and reliable backups even when everyone is online at once.
Because it's uncontended and backed by a Service Level Agreement, a leased line comes with guaranteed speeds, guaranteed uptime and rapid fix times if anything ever goes wrong. For businesses that live in Microsoft 365, run VoIP, or move large files, it removes the daily frustration of slow, unpredictable broadband.
CLI Secure handles the whole journey: we compare carriers to find the best price and lead time for your postcode, project-manage the install, configure your router and firewall, and then monitor and support the line for its lifetime. One partner, one bill, one number to call.
- Carrier comparison for best price & lead time
- Project-managed install with progress updates
- Router & firewall configured and secured
- Ongoing monitoring and UK-based support
› pricing
What a business leased line costs
A business leased line typically costs from £150 per month for 100Mbps, from £250 for 1Gbps and from £700 for 10Gbps in London, usually with free installation on a 36-month term. Dense carrier competition keeps London pricing well below the UK average.
"From" prices reflect typical carrier pricing across Greater London on 36-month terms; your exact price depends on your postcode and building. Free availability check — quotes usually returned the same working day.
› what's included
Built for performance and reliability
Symmetric speeds
Equal upload and download from 100 Mbps to 10 Gbps — perfect for cloud, VoIP and backups.
Uncontended & dedicated
The full bandwidth is yours alone, 24/7 — never shared or throttled at peak times.
Guaranteed SLA
Contractual uptime (typically 99.9%+) with rapid target fix times if a fault occurs.
Carrier-neutral pricing
We compare BT Openreach, Cityfibre, Virgin and more to find your best price and lead time.
Managed router & firewall
We configure, secure and monitor the edge so the line is business-ready from day one.
Scalable bandwidth
Burst or upgrade as you grow without re-cabling — future-proofed from the start.
› speed tiers
Which speed is right for you?
| Speed | Best suited to |
|---|---|
| 100 Mbps | Small-to-mid offices, ~25–50 staff |
| 500 Mbps | Growing, cloud-first teams |
| 1 Gbps | Cloud-heavy SMEs & busy multi-team sites |
| 10 Gbps | Data-intensive or multi-site aggregation |
Pricing depends on your postcode, carrier and contract term — get a tailored quote.
› is it right for you?
Signs your business is ready for leased lines
If several of these ring true, it's worth a conversation. Not sure? A quick, free call with our team will point you in the right direction.
- 25+ people share a single connection
- You rely on Microsoft 365, ERP or CRM in the cloud
- You run VoIP and need guaranteed call quality
- Broadband slows noticeably at peak times
- You host systems clients or remote workers must reach
- You need a contractual SLA for compliance or clients
› how it works
From quote to live, fully managed
Survey & compare
We check availability and compare carriers for your exact postcode, then recommend the best fit on price, lead time and SLA.
Order & plan
We place the order, run the site survey and agree a clear install plan and timeline — with progress updates throughout.
Install & configure
Carrier engineers install the circuit; we configure and secure your router and firewall, ready for day one.
Cutover & support
We manage the switch from your old connection with minimal disruption, then monitor and support the line for life.
› the difference
What changes when you switch to CLI Secure
before
- ✕Shared broadband that slows to a crawl at peak times
- ✕Slow uploads that choke video calls and cloud backups
- ✕No SLA — days of downtime with no guaranteed fix
- ✕Chasing carriers and installers on your own
with cli secure
- Dedicated, uncontended bandwidth — yours alone, 24/7
- Symmetric speeds for smooth calls, cloud and backups
- A guaranteed SLA with rapid target fix times
- One partner managing carriers, install and support
› faq
Leased Lines, answered
› explore & learn more
Related connectivity & further reading
Related services
Authoritative sources
External references for UK connectivity performance and network resilience best practice.
› 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.
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