Dark Fibre

Fully control your high capacity optical network with near-limitless scalability.

If you’re a hyperscaler, wholesale network provider or large organisation, you sometimes need complete control over your connectivity.

Dark Fibre is unused fibre with no active traffic. You design and operate a private, high capacity network on your own dedicated infrastructure, ideal for:

  • Core network expansion or backhaul
  • Data centre interconnect (DCI)
  • Real-time cloud, AI and IoT workloads
  • Customised, high‑security networks for regulated data

Choose your own hardware, network architecture, routing and security protocols. Extend your reach across the UK with our extensive Dark Fibre network.

Get a Dark Fibre quote today.

Why Dark Fibre?

Unlike managed fibre services, Dark Fibre gives you maximum control over your network, with:

Total flexibility

Leverage our UK-wide fibre network built for Critical National Infrastructure, custom-built fibre, or a third-party option.

Near-limitless scalability

Scale up your bandwidth and network reach nationwide.

Bespoke specification

Choose G652 and/or G655 fibre with duct and sub-duct options.

Built-in resilience

Customise your network architecture and route diversity for maximum resilience.

Availability and SLAs

Leading network availability and fault restoration agreements.

Outstanding support

24/7 helpdesk, ISO-certified cyber security, and industry-leading +75 NPS.

What our customers say

Looking for a Dark Fibre solution?

Leverage our high capacity UK-wide network to deploy Dark Fibre for data centre interconnects, backhaul or core networks nationwide.

Our specialists work with you to map the optimal route, overcome challenges and plan for future growth. The result is Dark Fibre infrastructure designed for your long-term success.

Dark Fibre FAQs

  • When should you choose Dark Fibre over managed Optical Wavelengths (“lit fibre”)?

    Dark Fibre is the right choice when you need full control over how your network is designed, operated and scaled. Managed Optical Wavelengths offer high capacity connectivity without the need to run and maintain the underlying infrastructure.

  • Is Dark Fibre more cost-effective than managed wavelength services?

    Dark Fibre can be more cost-effective over time if you need very high capacity and can fully utilise the infrastructure, as costs don’t scale with bandwidth. Managed Optical Wavelengths offer lower upfront investment and fixed, defined capacity, making them a better fit when you want predictable costs without managing your own network.

  • Where is Dark Fibre available in the UK?

    Dark Fibre is available across our extensive UK-wide network, connecting key cities, data centres and exchanges nationwide. Where coverage isn’t in place, we can also support custom builds or access via third-party networks where needed.

    Explore our UK-wide Dark Fibre network

  • Is Dark Fibre suitable only for large organisations?

    Dark Fibre is best suited to organisations with high bandwidth demands and the capability to design, operate and maintain their own network. However, it can also work for smaller organisations with specific performance or control requirements.

  • What equipment do you need to use Dark Fibre?

    To use Dark Fibre, you need your own equipment such as routers, switches and optical hardware including transceivers and transponders, along with supporting transmission components. Together, these light the fibre and give you direct control over capacity, routing and performance.

  • Who is responsible for maintaining a Dark Fibre network?

    With Dark Fibre, you’re responsible for operating and maintaining the equipment you deploy. Neos Networks maintains the underlying fibre infrastructure, including network availability and fault repair, with defined restoration SLAs.

  • What speeds can you achieve with Dark Fibre?

    Speeds on Dark Fibre are determined by the equipment you deploy and the capacity of the fibre. In practice, that means you can run at whatever bandwidth your infrastructure supports, rather than being limited to the predefined speeds of a managed service.

  • How long does it take to deliver Dark Fibre?

    If the route is on‑net, Dark Fibre delivery typically takes around 30 to 90 days. New builds requiring civil works or permits usually take 90 to 180 days. More complex projects, such as those involving wayleaves or major construction, can take longer.

  • How can I get a Dark Fibre quote?

    Fill in the Get a Dark Fibre quote form above. Or if you’d like to discuss your project with a Dark Fibre expert, contact us. We'll work with you to design the right solution and provide pricing based on your route and network requirements.

Questions?

Get in touch to talk to one of our Dark Fibre experts.

Contact us

Discover more

Check out our Dark Fibre brochure

Download Dark Fibre brochure