A new electricity or gas connection has two contestable layers you can shop: the firm that designs and builds the network (the ICP or UIP) and the operator that adopts and owns it for life (the IDNO or IGT). This directory lists established, identifiable UK firms in both layers, with the accreditations each publishes and the public registers to check them. It is a reference, not a ranking.
This is not a ranking, a league table or a scored comparison, and inclusion is not endorsement. These are established, identifiable UK firms, listed with the legal entity and the accreditations each one publishes, corroborated against Companies House, the Ofgem public register and the Independent Networks Association (INA) member list. Accreditation scopes change, so always confirm the live scope on the relevant public register (see verify it yourself) before you appoint anyone. Purely Energy is independent and is not paid by any firm listed here. Compiled on 2026-06-22.
The two layers you can actually shop
Your regional network monopoly (the DNO for electricity, the GDN for gas) is fixed by location and cannot be competed. What can be competed sits in two layers, and a good tender shops both.
Who builds it: the ICP or UIP
The contestable construction (cabling, jointing, ducting, civils, substations, gas mains and service pipes) can be put out to a NERS or GIRS accredited firm in competition with the network. This is where tendering moves the price. The detail by fuel sits on our guides to a new electricity connection and a new gas connection.
Who owns it: the IDNO or IGT
An Ofgem-licensed independent operator can adopt and own the new network instead of the regional monopoly. Because it earns future use-of-system revenue, it can return a capitalised asset value that offsets your build cost. How that offset weighs against the build sits in our guide to new connection costs.
Some firms hold both: they build as an ICP or UIP and adopt through their own IDNO and IGT licences. That is convenient, but the independence of the asset-value offer is worth protecting. New to the acronyms? Start with the new energy connections hub or our new connections FAQs.
How to choose: what actually makes one firm the right one
There is no single best provider, because the right firm depends on your voltage, your fuel and your region. The defensible way to choose is to check each one against the same criteria, and to verify every claim on a public register rather than a brochure.
NERS accreditation with the right scope (electricity)
NERS proves an ICP can design and build electricity connections to network standards. It is scoped: a firm accredited only for LV design is not qualified to self-deliver an 11kV or 33kV connection.
Verify: Search the LRQA NERS register and check the listed scope covers your voltage, activities and DNO region, not just that the firm appears.
GIRS accreditation with matching scope (gas)
GIRS is the gas equivalent for new infrastructure up to 7 bar, scoped into categories (mains, services, alterations). Wrong-scope gas work is a safety and liability risk.
Verify: Search the LRQA GIRS register and confirm the category and pressure tier match your works.
Ofgem licence for the adopting IDNO or IGT
The operator that owns and runs your network for its life must hold a valid Ofgem distribution or gas transporter licence. Only a licensed IDNO or IGT can make an asset-value payment to adopt a network.
Verify: Search the Ofgem public register for the licence, then cross-check the Companies House number to confirm the entity and that it is solvent.
ISO 9001, 14001 and 45001 (verified, not just a logo)
These show disciplined quality, environmental and health-and-safety processes, the highest-risk dimension of live cable and gas works. They matter most when UKAS-accredited.
Verify: Verify the certificate, not the logo, on UKAS CertCheck.
SSIP / CHAS health-and-safety pre-qualification
A current SSIP-member certificate (CHAS, SMAS, SafeContractor, Constructionline) shows the firm has passed third-party health-and-safety pre-qualification, often a hard requirement for larger works.
Verify: Ask for the certificate and check it on the scheme's portal, with an expiry date in the future.
NRSWA / street-works qualifications
Any excavation in or alongside the public highway needs operatives and supervisors holding the correct street-works qualifications. Unqualified work is illegal and invalidates reinstatement guarantees.
Verify: Ask for the names and card numbers of the supervisor and operatives who will be on your site and check them against the Street Works Qualifications Register.
Asset-value offer quality and financial ring-fencing
An IDNO funds its asset-value payment from future use-of-system revenue and becomes your site's permanent network owner. A bigger headline figure with weak service terms or a thin entity is not the better deal.
Verify: Ask each IDNO to itemise the asset-value calculation, the adoption-agreement terms, the guaranteed standards of service and the ring-fencing arrangements, and confirm solvency at Companies House.
Insurance, references and a comparable track record
Civil and electrical or gas works carry real liability. References on comparable schemes (same voltage, similar complexity, same region) are the best predictor of delivery.
Verify: Request current insurance certificates and two or three references on recent comparable jobs, then call them about programme adherence and cost certainty against the original quote.
Red flags to walk away from
Claims an accreditation (NERS, GIRS, WIRS) but does not appear on the LRQA register, or appears with a narrower scope than the works need.
An adopting IDNO or IGT you cannot find on the Ofgem public register, or whose Companies House entity differs from the one named in the contract.
Displays an ISO logo but cannot produce a UKAS-accredited certificate that verifies on CertCheck.
Cannot name the street-works-qualified operatives and supervisor for your site.
Pressure to sign quickly on a headline asset value without itemising the assumptions, adoption terms or financial ring-fencing.
A single very low quote with no scope breakdown and no clarity on who adopts the network long-term.
Bundles the ICP build and IDNO adoption from one group without letting you compare the asset value against other licensed adopters.
The directory
Connection providers and independent network owner-operators, in no particular order. Each card shows the role each firm plays, the utilities it connects, the accreditations it publishes, its coverage and its ownership. Confirm the live accreditation scope on the public register before appointing. For the groundworks and civils layer, see our directory of utility siteworks companies.
Eclipse Power Networks
Eclipse Power Networks Ltd (Milton Keynes)
IDNO
Utilities: Electricity
A pure-play independent distribution network operator. Designs, owns and maintains electricity networks across Great Britain, adopting assets built by NERS-accredited ICPs, and serving industrial sites, EV hubs, battery storage and data centres.
Accreditations published
Ofgem IDNO licenceAdopts only from NERS-accredited ICPs
Coverage
Great Britain-wide.
Ownership
Owned by the Octopus Sky Fund; acquired the Vattenfall UK IDNO (2025).
Energy Assets Networks Ltd / Energy Assets Pipelines Ltd (Livingston)
ICPIDNOIGTMAM
Utilities: Electricity, Gas, Fibre
Nationwide multi-utility connections provider and final-mile network owner, and a major independent meter asset manager. Delivers large-scale contestable electricity and gas connections, then owns the adopted network.
Accreditations published
NERSGIRSWIRSOfgem IDNO licenceOfgem IGT licenceOfgem-accredited MAM
Coverage
Great Britain-wide; large-scale industrial, commercial and residential.
Ownership
Infrastructure consortium (sale to Macquarie Asset Management agreed 2026).
ESP Utilities Group Ltd (Leatherhead); water NAV via ESP Water Ltd
IDNOIGTNAV
Utilities: Electricity, Gas, Water
A long-established last-mile network owner-operator, with over a million live connections. Adopts, owns and operates electricity, gas and water networks built by accredited third-party ICPs and UIPs rather than building them itself.
Accreditations published
Ofgem IDNO licenceOfgem IGT licenceOfwat NAV (ESP Water)
Coverage
UK-wide; predominantly residential with industrial and commercial.
NG Bailey Ltd; connections delivered as Freedom / Power Solutions
ICPCivils
Utilities: Electricity
NERS-accredited ICP delivering end-to-end electrical connection and infrastructure works (substations, overhead lines, underground cables) at 11kV, 33kV and up to 132kV for DNOs, critical national infrastructure, data centres and private network owners, with associated civils.
Independent multi-utility connections provider that designs and builds electricity, gas and water connections and can adopt and own the assets through its own IDNO and IGT licences. Covers residential, industrial, commercial, EV and HV work.
Accreditations published
NERSGIRSOfgem IDNO licenceOfgem IGT licence
Coverage
Mainland UK.
Ownership
Fulcrum group (formerly Fulcrum Utility Services).
Part of BUUK Infrastructure (Woolpit, Bury St Edmunds)
UIPICPIDNOIGT
Utilities: Electricity, Gas, Water, Fibre, Heat
One of the UK's pioneering multi-utility infrastructure businesses, and the first company licensed as an independent gas transporter. Designs, builds, owns and operates networks for new developments and adopts the finished assets.
Accreditations published
NERSGIRSWIRSMURSISO 9001/14001/45001CHAS
Coverage
UK-wide; residential, commercial and mixed-use developments.
Independent network owner that adopts, owns and operates last-mile electricity (and gas) networks for new developments, working with NERS-accredited ICPs from design and build through commissioning and adoption.
Accreditations published
Ofgem IDNO licenceAdopts from NERS-accredited ICPs
Coverage
UK-wide.
Ownership
Indigo Networks group (Indigo Power, Indigo Gas, IndigoWater).
Last Mile Infrastructure Group Ltd; networks via Last Mile Electricity / Last Mile Gas
UIPICPIDNOIGTNAV
Utilities: Electricity, Gas, Water, Fibre, Heat
A major last-mile network business in Great Britain. Build delivery runs through the Energetics and UKPS brands; adoption and long-term ownership run through its IDNO, IGT and water (NAV) licences.
Accreditations published
NERSGIRSWIRSOfgem IDNO licenceOfgem IGT licenceOfwat NAV
Coverage
Great Britain-wide.
Ownership
Infracapital and Macquarie Asset Management (full Macquarie ownership agreed 2026).
Independent multi-utility network operator that adopts, owns and maintains last-mile electricity, gas and water connections for new developments, licensed to adopt low voltage through to 132kV electricity and gas at 7 bar and below.
Accreditations published
Ofgem IDNO licence (LV to 132kV)Ofgem IGT licenceWater NAV
Coverage
Great Britain-wide.
Ownership
Joint venture between J. Murphy & Sons (Murphy) and SGN.
The Independent Connection Provider Ltd (Northampton)
ICP
Utilities: Electricity, Gas
Independent connection provider accredited to design and construct new electricity and gas networks, from single connections and EV chargers to commercial developments and housing estates, with in-house cabling, jointing, substation and civils capability.
Accreditations published
NERSGIRSGas Safe Register
Coverage
UK-wide; electricity LV to 132kV plus routine gas connections.
UK Power Networks Services (Contracting) Ltd; the commercial arm, distinct from the regulated DNO
ICP
Utilities: Electricity
Established national ICP delivering high-voltage connections with extensive in-house design and engineering. Manages both the contestable and non-contestable elements of a connection, and adopts and operates private electricity networks for owners.
Accreditations published
NERS-accredited ICP for contestable works
Coverage
UK-wide; complex and large-scale connections up to 132kV.
Multi-utility connections provider and one of the few firms that is both an ICP and an Ofgem-licensed IDNO. Installs electricity, gas, water, fibre and heat infrastructure on developments, including district heat networks, with its own civils delivery.
Do not take a logo or a brochure at face value. Every accreditation above is checkable on a free public register, and the scope listed there is what counts, not the claim. Confirm a firm holds the right accreditation, at the right scope, for your voltage, fuel and region before you appoint it.
Confirms an ISO 9001/14001/45001 certificate is real, live and UKAS-accredited (not just a logo).
How Purely runs a connection tender
A list of firms is only useful if you know how to put them against each other. We run the tender as one managed process, with every margin disclosed and every claim checked on the registers above.
01One voltage-correct scope. We write a single technical scope that matches your load and fuel, so every firm quotes the same job and the numbers are genuinely comparable.
02Tender the build. We put accredited ICPs and UIPs against the network price on the contestable works, on both cost and programme, with the non-contestable line shown separately because it cannot be competed.
03Compete the asset value. We split the IDNO or IGT adoption out as its own competition, so the asset-value offset is won on its merits rather than bundled in by whoever built the network.
04Verify every claim. We confirm each NERS, GIRS, Ofgem licence and ISO certificate on the public register, and check the legal entity at Companies House, before anyone is appointed.
Send us the site address and the anticipated load. We write the scope, tender the build, compete the IDNO or IGT adoption, verify every accreditation, and place the supply contract at the end, with every margin disclosed.