What Is Full-Fibre Broadband?

The Difference Between Full-Fibre and "Fibre Broadband"

The UK's most widely advertised "fibre broadband" product is actually a hybrid technology called FTTC — Fibre to the Cabinet. With FTTC, a fibre-optic cable runs from the telephone exchange to a green street cabinet on the pavement. From that cabinet onwards, the signal travels to your home over the existing copper telephone wire.

Copper is slower and more susceptible to signal degradation than fibre. The further your property is from the street cabinet, the slower the maximum achievable speed. A house 50 metres from the cabinet might receive close to 80 Mbit/s; a house 400 metres away might only reach 30–40 Mbit/s; a house 800 metres or more away might receive considerably less. This variability makes FTTC an inconsistent technology from one street to the next.

Full-fibre broadband — formally known as FTTP (Fibre to the Premises) or occasionally FTTH (Fibre to the Home) — eliminates the copper segment entirely. A fibre-optic cable runs unbroken from the exchange or local aggregation node all the way to the wall of your building. There is no cabinet handoff, no copper tail, and no distance-related speed penalty.

Because both products are often marketed as "fibre broadband" by providers, many consumers do not realise they have a copper-based connection until they look at the technical details. Ofcom's data — and PlainBroadband's coverage maps — distinguish the two precisely: a full-fibre figure refers strictly to FTTP infrastructure, not FTTC.

How Full-Fibre Speeds Compare

Full-fibre connections are sold at a range of speed tiers, most commonly 100 Mbit/s, 500 Mbit/s, and 1 Gbit/s (1,000 Mbit/s) download, often with matching upload speeds. This symmetry — equal upload and download — is a defining characteristic of FTTP. FTTC services typically deliver upload speeds of only 10–20 Mbit/s even when the download reaches 80 Mbit/s.

Ofcom defines superfast broadband as any connection capable of at least 30 Mbit/s download. FTTC qualifies under this definition, which is why superfast coverage figures in the UK are high — above 95% nationally by the time of the Connected Nations 2025 report — while full-fibre coverage is lower, because FTTC does not count as full-fibre.

Ofcom defines ultrafast broadband as connections capable of at least 300 Mbit/s, and gigabit-capable broadband as connections capable of at least 1,000 Mbit/s. Full-fibre infrastructure qualifies under all three definitions. For a deeper comparison of these tiers, see our guide to Full-Fibre vs Gigabit-Capable Broadband.

Why Full-Fibre Is Considered Future-Proof

The physics of fibre optics give full-fibre infrastructure a significant advantage over copper-based alternatives. A single strand of optical fibre has theoretical capacity many times greater than any current broadband product. Upgrading a full-fibre network to support faster speeds typically requires only changes to the electronic equipment at each end of the fibre — the physical cable itself can remain in place indefinitely.

Copper wire, by contrast, is approaching its practical speed limits. FTTC networks that currently deliver 80 Mbit/s can be enhanced with technologies such as G.fast and XGFast, but these are stop-gap improvements. Each enhancement requires new equipment at street level and still cannot match the sustained performance or upgrade headroom of pure fibre.

This is why the UK government's Project Gigabit programme — which funds broadband build-out in commercially unviable areas — specifies full-fibre as its required technology standard. Public subsidy goes only to full-fibre deployments, not to FTTC upgrades, reflecting the policy view that FTTP is the infrastructure to build once and keep for decades.

Coverage vs Take-Up: An Important Distinction

When Ofcom reports that a given local authority has, say, 75% full-fibre coverage, it means that 75% of premises in that area have full-fibre infrastructure physically passing the building — a cable exists that could deliver a full-fibre connection. It does not mean 75% of residents have subscribed to a full-fibre service.

Take-up — the proportion of premises that have actually ordered a full-fibre product — is consistently lower than coverage. This gap exists because:

• Many residents are still under contract with a legacy FTTC or cable provider.
• Some residents are unaware that full-fibre is now available to them.
• Newly built networks take time to attract subscribers; coverage naturally precedes take-up.
• Price differences between full-fibre and copper-based products can influence switching decisions.

On PlainBroadband, the full-fibre take-up figures shown on local authority pages measure what share of all premises in an area have subscribed to a full-fibre service — a different and typically lower number than coverage. An area with high coverage but low take-up has the infrastructure in place but residents still on older products.

Why Availability Varies So Much Across the UK

Building full-fibre to a premises costs broadly the same per connection regardless of location. However, the revenue potential per connection varies enormously with population density. In a city centre, a single trench may pass hundreds of flats; in a remote rural hamlet, the same expenditure might reach only twenty houses.

This commercial logic explains why London boroughs, metropolitan districts, and urban areas in England have consistently high full-fibre coverage, while rural local authorities in Scotland, Wales, and South West England lag significantly. Operators build where the economics work first. Publicly funded programmes such as Project Gigabit and, in Northern Ireland, Project Stratum exist specifically to reach premises that the commercial market will not serve unaided.

Premises that cannot receive a connection capable of at least 10 Mbit/s download and 1 Mbit/s upload may be entitled to request one under the Universal Service Obligation. Our dedicated guide on the broadband Universal Service Obligation explains how the USO works and who the eligible providers are.

How to Check Whether Full-Fibre Is Available at Your Address

PlainBroadband shows coverage at the level of local authority districts and Westminster constituencies, using Ofcom's Connected Nations 2025 dataset. These area-level figures are useful for understanding the local connectivity landscape, but they cannot tell you whether a specific address has full-fibre available.

For address-level availability checking, the following routes are available:

• Ofcom's broadband availability checker — Ofcom publishes a postcode-level checker that draws on the same network data as its Connected Nations reports.
• Provider postcode checkers — Openreach, CityFibre, Hyperoptic, Gigaclear, and other network builders publish online tools that show whether their full-fibre network passes a given address.
• Comparison services — Uswitch, MoneySavingExpert's Broadband Unbundled, and similar services aggregate provider availability and pricing by postcode.

If multiple providers show full-fibre available at your address, it is worth comparing not just headline speeds but contract length, setup fees, and the network operator underlying the service — some retail ISPs sell products on the same underlying Openreach or CityFibre infrastructure.

Full-Fibre on PlainBroadband

Every local authority and constituency page on PlainBroadband displays the full-fibre coverage percentage for that area, derived from Ofcom's Connected Nations 2025 data. You can use the local authority browser to sort all 361 districts by full-fibre coverage and identify where in the national league table any given area sits. The rankings page also shows how take-up compares to coverage, which reveals where infrastructure investment is ahead of consumer adoption.