G.Fast Broadband: The Business Guide

G.Fast — sometimes stylised as G.fast — is a broadband technology that emerged as a stepping stone between FTTC and full fibre FTTP. By moving the fibre closer to premises and using a short copper run from a smaller distribution point rather than a street cabinet, G.Fast can deliver download speeds up to 330Mbps and upload speeds up to 50Mbps. In theory, it offers near-fibre performance without the full cost of laying fibre all the way to each building.

How G.Fast Works

G.Fast builds on the FTTC model but with a critical difference: the copper run is much shorter. Where FTTC uses a street cabinet serving potentially hundreds of premises within a few hundred metres, G.Fast uses small distribution point units (DPUs) that are placed much closer to the building — sometimes attached to telegraph poles or lamp posts just metres away.

The shorter copper run makes a significant difference to achievable speeds. DSL technologies like FTTC are highly sensitive to line length — every 100 metres of additional copper costs speed. With a 50–100 metre copper run from a G.Fast DPU, speeds in the hundreds of megabits per second become achievable on standard copper infrastructure.

G.Fast Speeds in Practice

BT Openreach has deployed G.Fast in selected areas, typically delivering:

• Download speeds: 100–330Mbps, depending on copper run length and line quality
• Upload speeds: 30–50Mbps

These speeds are substantially better than standard FTTC but fall short of the symmetric gigabit speeds that FTTP delivers. The asymmetry between download and upload — while much improved over FTTC — remains a characteristic of the technology.

G.Fast Availability

G.Fast has had a limited and somewhat disappointing rollout in the UK. Openreach deployed G.Fast in a series of trial areas and some commercial deployments, but the programme was not scaled to the nationwide level that was initially anticipated. The reasons are partly commercial (FTTP delivers better long-term value and Openreach has shifted investment focus) and partly technical.

As a result, G.Fast is available in a relatively small number of UK premises. If your business is in a G.Fast coverage area, it may appear as an option in your ISP's availability checker alongside FTTC and FTTP products.

G.Fast vs FTTP: Should You Wait for Full Fibre?

For businesses in areas where both G.Fast and FTTP are becoming available, the recommendation is clear: prioritise FTTP. Full fibre delivers:

• Higher maximum speeds (up to 1Gbps and beyond)
• Better symmetry (upload speeds proportionally much closer to download)
• Future-proof infrastructure that will not require replacement
• More consistent performance regardless of line conditions

G.Fast is most relevant for businesses in areas where FTTC is delivering inadequate speeds but where FTTP is not yet available. In that specific scenario, G.Fast can be a meaningful improvement. However, given the continuing pace of FTTP rollout, waiting for full fibre is often the better strategic decision for businesses that can sustain their current connection in the interim.

G.Fast for Business Pricing

Where G.Fast is available, business pricing is typically in the range of £40–£65/month for a 24-month contract — broadly similar to FTTP pricing at equivalent speeds. The overlap in pricing makes FTTP an even more compelling choice where both are available, since FTTP offers superior performance at comparable cost.

Should Your Business Invest in G.Fast?

For most UK businesses considering a connectivity upgrade, G.Fast is not the primary focus. The more relevant question is whether FTTP is available at your premises via Openreach, CityFibre or other networks. If not, and your current FTTC is genuinely inadequate, G.Fast may be worth evaluating. But in most scenarios, the combination of limited availability and the proximity of FTTP to most UK premises makes G.Fast a niche consideration rather than a mainstream recommendation.