- Physical Infrastructure Access (PIA) is a regulated product that Ofcom requires Openreach to offer, letting other providers use its ducts and poles to deploy their own fibre.
- Ofcom designed PIA so it can be used for any purpose, including residential and business broadband, not only to serve Openreach's own network.
- Charges for duct and pole access are price-controlled by Ofcom under its Wholesale Fixed Telecoms Market Review, with a published charge control framework.
- PIA forms part of Ofcom's strategy to support competing fibre networks, often called altnets, building infrastructure across the UK.
- Openreach publishes a PIA Reference Offer setting out the technical and commercial terms operators must follow when accessing ducts and poles.
A duct and pole agreement lets a rival builder run its fibre through Openreach's existing ducts and poles under Ofcom's Physical Infrastructure Access regime, cutting build costs and widening consumer choice.
Last reviewed: June 2026
What a duct and pole agreement actually covers
Beneath most UK streets sits a hidden network of plastic ducts, and along many roads run timber and steel poles. For decades this passive infrastructure carried only the incumbent network. A duct and pole agreement is the commercial and regulatory arrangement that allows a separate communications provider to thread its own fibre cables through those same ducts and string them along those same poles, rather than digging fresh trenches or planting new poles of its own.
The arrangement matters because civil engineering is by far the largest cost in building a fibre network. Trenching across a town can absorb most of a deployment budget. By reusing existing ducts and poles, a builder avoids much of that expense and disruption. The agreement governs how that sharing happens: which assets can be used, how a builder surveys and reserves space, what it pays, and who is responsible for repairs and safety. In the UK this sharing is not left purely to private negotiation. Ofcom regulates it through a framework known as Physical Infrastructure Access.
How the Physical Infrastructure Access regime works
Physical Infrastructure Access, usually shortened to PIA, is a regulated wholesale product. Ofcom has determined that Openreach holds significant market power in the relevant fixed telecoms markets, and one of the remedies it imposes is an obligation on Openreach to give other providers access to its ducts and poles on fair and reasonable terms. This is set out in Ofcom's Wholesale Fixed Telecoms Market Review, the periodic decision document that defines the rules for the wholesale broadband market.
A crucial feature of the current regime is that PIA can be used for any purpose. Earlier versions of duct and pole access were restricted to specific use cases, which limited their value to competitors. Ofcom removed that restriction so that an operator can use the ducts and poles to build a full fibre network serving homes and businesses, including in competition with Openreach itself. To make the obligation workable, Openreach publishes a PIA Reference Offer, a detailed document covering surveys, capacity checks, repair responsibilities, and the process for adding cables and equipment.
The mechanism in practice runs through a defined operational pipeline. An operator first uses Openreach data and survey tools to plan a route, then raises a request to check whether a given duct or pole has spare capacity. Where ducts are blocked or collapsed, the regime allows for repair and clearance work so the route can be made usable, and Ofcom has pressed for the costs and timescales of that work to be reasonable so they do not become a hidden barrier. Pole access is treated separately from underground duct access, because loading a pole with additional cabling raises distinct structural and safety questions that the Reference Offer addresses. The intention across all of this is that a competitor faces a predictable, repeatable process rather than ad hoc negotiation each time it wants to extend its network down another street.
What altnets do with the infrastructure
Alternative network providers, commonly called altnets, are the main users of PIA. These are companies building fibre networks independently of Openreach, often focusing on particular towns, cities, or rural areas. Using PIA, an altnet surveys a route, identifies usable duct and pole capacity, reserves it, and then installs its own fibre. The fibre, electronics, and customer relationships belong to the altnet; only the underlying ducts and poles are shared.
This model changes the economics of entering the market. A new builder no longer has to replicate the entire passive network from scratch, which historically created a near-insurmountable barrier. Instead it can concentrate investment on the active fibre and on connecting premises. The result has been a wave of fibre deployment by competing networks across the UK, supported by Ofcom's deliberate policy of encouraging infrastructure competition rather than relying on a single national builder.
How PIA shapes the broadband market
The table below sets out the main ways the PIA regime influences the broadband market and, ultimately, the choices available to households and businesses. The figures and mechanisms described are framework features defined by Ofcom rather than guaranteed outcomes in any single area.
| Market factor | Effect of the PIA regime | Who benefits |
|---|---|---|
| Build cost | Reuse of ducts and poles avoids most trenching, the largest cost in deployment | Altnets and investors |
| Barriers to entry | New builders no longer need to replicate the full passive network | New entrants |
| Network coverage | Faster fibre roll-out, including to areas a single builder might deprioritise | Consumers and businesses |
| Pricing tension | Charge-controlled access keeps wholesale input costs predictable | Retail providers |
| Retail choice | More competing networks can mean more providers at a single address | Households |
What it means for consumer choice and pricing
For a household, the PIA regime is largely invisible, yet it underpins much of the choice now appearing on the market. Where an altnet has built fibre using shared ducts and poles, an address may have a genuine alternative to the incumbent network, sometimes more than one. That competition can influence pricing, package design, and service quality, because providers know a dissatisfied customer may have somewhere else to go.
It is worth being clear about what the regime does not guarantee. PIA makes competing builds cheaper and easier, but it does not promise that every street will gain multiple networks. Commercial decisions, local geography, and the practical availability of duct and pole capacity all play a part. The role of the regime is to remove an artificial barrier, not to dictate where each cable is laid. Ofcom monitors the market through successive reviews and adjusts the rules where it judges competition is not developing as intended.
How the rules are kept fair
The fairness of duct and pole access rests on regulation rather than goodwill. Because Openreach owns the assets and also competes downstream, Ofcom imposes obligations designed to stop it favouring its own retail and wholesale arms. These include the requirement to publish a Reference Offer, equivalence principles so that competitors are treated comparably to Openreach's own divisions, and a charge control that limits what can be charged for access.
Disputes about the terms or operation of PIA can be brought to Ofcom, which has statutory powers to investigate and resolve disagreements between communications providers. The combination of a published offer, price control, and a dispute route is intended to give altnets enough certainty to invest while preventing the asset owner from quietly undermining the competition the regime is meant to foster.
Equivalence is the technical heart of the fairness model. Under Ofcom's rules, Openreach is expected to provide PIA on terms, and through processes and systems, comparable to those it uses for its own fibre build. That means an altnet should not face slower surveys, worse data, or higher effective costs than Openreach's own deployment teams. Ofcom also gathers performance information and can require Openreach to report on how the product is operating, so that any drift away from genuine parity becomes visible. The charge control itself is set within the Wholesale Fixed Telecoms Market Review and is periodically reset, which keeps the access price tethered to underlying costs rather than allowed to float upward. For households this regulatory plumbing is unseen, yet it is the reason a competing network can appear at an address at all.
Frequently Asked Questions
What is a duct and pole agreement?
It is the commercial and regulatory arrangement that lets one communications provider run its fibre through ducts and along poles owned by another, usually Openreach. In the UK these agreements operate within Ofcom's Physical Infrastructure Access framework, which sets the terms and prices. The arrangement covers surveys, capacity, charges, and repair responsibilities.
How do altnets use BT's infrastructure?
Altnets survey a route, identify spare capacity in existing ducts and on poles, reserve it, and install their own fibre and equipment. Only the passive ducts and poles are shared; the fibre and the customer relationship belong to the altnet. This lets them build networks without digging most of their own trenches.
What is Physical Infrastructure Access?
Physical Infrastructure Access, or PIA, is a regulated wholesale product that Ofcom requires Openreach to offer. It obliges Openreach to let competing providers use its ducts and poles on fair terms and for any purpose, including building rival broadband networks. Ofcom sets the rules through its Wholesale Fixed Telecoms Market Review.
Does PIA help consumers?
PIA lowers the cost of building competing fibre networks, which can lead to more providers and more choice at a given address. It does not guarantee multiple networks everywhere, because commercial and geographic factors still apply. Its purpose is to remove an artificial barrier to competition rather than to dictate where cables are laid.
Who regulates duct and pole access?
Ofcom regulates duct and pole access in the UK. It defines the obligations on Openreach, controls the prices that can be charged, requires a published Reference Offer, and can resolve disputes between providers. These powers come from its role as the communications regulator under the relevant legislation.
