Infrastructure companies in the UK

Whito directory

Infrastructure companies in the UK

41 firms listed, 23 September 2026. Each checked at Companies House. We add firms one at a time and publish the real count here.

This is a directory of the companies behind UK infrastructure: the firms that build it, run it, own the networks and advise on it. It is not a directory of projects. For projects, the government publishes the UK Infrastructure Pipeline: 734 projects worth £718bn, as at its 9 March 2026 edition.

The listings

41 firms. Listed A to Z: none has been claimed yet, so none is marked Verified. Browse by group: Contractors (10) · Utilities (20) · Operators and concessionaires (5) · Advisers (6).

FirmLegal nameCompany numberGroup
AECOMAECOM LIMITED01846493Adviser
Anglian WaterANGLIAN WATER SERVICES LIMITED02366656Utility
Associated British PortsASSOCIATED BRITISH PORTSZC000195Operator
AtkinsRéalisATKINSRÉALIS UK LIMITED00688424Adviser
Balfour BeattyBALFOUR BEATTY GROUP LIMITED00101073Contractor
CadentCADENT GAS LIMITED10080864Utility
Connect PlusCONNECT PLUS (M25) LIMITED06683845Operator
CostainCOSTAIN LIMITED00610201Contractor
Eastern Power NetworksEASTERN POWER NETWORKS PLC02366906Utility
Forth PortsFORTH PORTS LIMITEDSC134741Operator
Galliford TryGALLIFORD TRY CONSTRUCTION LIMITED02472080Contractor
HS1HS1 LIMITED03539665Operator
JacobsJACOBS U.K. LIMITED02594504Adviser
KierKIER CONSTRUCTION LIMITED02099533Contractor
Laing O’RourkeLAING O’ROURKE DELIVERY LIMITED04309402Contractor
London Power NetworksLONDON POWER NETWORKS PLC03929195Utility
Morgan Sindall InfrastructureMORGAN SINDALL CONSTRUCTION & INFRASTRUCTURE LTD04273754Contractor
Mott MacDonaldMOTT MACDONALD LIMITED01243967Adviser
MurphyJ. MURPHY & SONS LIMITED00492042Contractor
National Grid Electricity TransmissionNATIONAL GRID ELECTRICITY TRANSMISSION PLC02366977Utility
NGED East MidlandsNATIONAL GRID ELECTRICITY DISTRIBUTION (EAST MIDLANDS) PLC02366923Utility
NGED South WalesNATIONAL GRID ELECTRICITY DISTRIBUTION (SOUTH WALES) PLC02366985Utility
NGED South WestNATIONAL GRID ELECTRICITY DISTRIBUTION (SOUTH WEST) PLC02366894Utility
NGED West MidlandsNATIONAL GRID ELECTRICITY DISTRIBUTION (WEST MIDLANDS) PLC03600574Utility
Northern Gas NetworksNORTHERN GAS NETWORKS LIMITED05167070Utility
Severn TrentSEVERN TRENT WATER LIMITED02366686Utility
Sir Robert McAlpineSIR ROBERT MCALPINE LIMITED00566823Contractor
SkanskaSKANSKA CONSTRUCTION UK LIMITED00191408Contractor
South Eastern Power NetworksSOUTH EASTERN POWER NETWORKS PLC03043097Utility
SP DistributionSP DISTRIBUTION PLCSC189125Utility
SP ManwebSP MANWEB PLC02366937Utility
SP TransmissionSP TRANSMISSION PLCSC189126Utility
SSEN Distribution (North)SCOTTISH HYDRO ELECTRIC POWER DISTRIBUTION PLCSC213460Utility
SSEN Distribution (South)SOUTHERN ELECTRIC POWER DISTRIBUTION PLC04094290Utility
SSEN TransmissionSCOTTISH HYDRO ELECTRIC TRANSMISSION PLCSC213461Utility
Thames WaterTHAMES WATER UTILITIES LIMITED02366661Utility
TidewayBAZALGETTE TUNNEL LIMITED09553573Operator
Turner & TownsendTURNER & TOWNSEND LIMITED06468643Adviser
United UtilitiesUNITED UTILITIES WATER LIMITED02366678Utility
VolkerFitzpatrickVOLKERFITZPATRICK LIMITED02387700Contractor
WSPWSP UK LIMITED01383511Adviser

Each was checked at Companies House on 23 September 2026. Two more firms are held until their Companies House filings update.

Who can be listed

Four kinds of firm, as described on the infrastructure hub:

  1. Contractors, main and specialist
  2. Operators and concessionaires
  3. Utilities
  4. Advisers, such as engineering, cost, planning and legal firms

A firm goes in the group that matches the work it has done, not the one it would like to be in.

The listing rules

These rules are stricter than the ones for our trade listings. We expect the people checking these firms to need the legal entity, not just the trading name, so the rules start there.

1. A Companies House number, or no listing. Every firm here must match an active company, LLP or other registered entity at Companies House. We show the legal name, the number, the status and the date we checked. If a firm trades under a brand, we show both names and say which one holds the contracts. A firm that is dissolved, or in liquidation on the day we check, is not listed.

2. What they actually build, from a public source. We describe work a firm has completed or is delivering now. That means work named on its own website, in a published contract award, or in a regulator’s record. We do not publish capability statements (“we can deliver schemes of any size”). If we cannot find public evidence of a type of work, we leave it out.

3. Region, in plain words. We show the registered office town and the regions the firm says it works in. Where a firm works nationally, we say “UK-wide” and nothing grander.

4. No paid rank. Nobody can pay to appear, to move up, or to be left out. The default order is the same as on every Whito directory page. Verified listings, where the firm has claimed its listing and confirmed its details, come first. After that the list is alphabetical. Claiming is free.

5. Figures only from filings. If a profile shows turnover or headcount, it comes from accounts filed at Companies House, with the period stated. We do not repeat figures from press releases or pitch decks.

6. No stars, no reviews, no badges for sale. We do not host reviews. Scheme and framework memberships are shown only where we can point to a public record, and are labelled “stated” where we cannot.

7. Public bodies are explained, not listed. Public bodies that commission infrastructure are explained in our research notes, not listed as businesses. HS2 Ltd and National Highways buy the work rather than supply it, so none of the four groups fits them.

What a listing shows

FieldWhere it comes from
Legal name and company numberCompanies House
Status and date checkedCompanies House, on the date shown
Trading nameThe firm’s own website
GroupContractor, operator, utility or adviser
What they build or runPublic source, linked
Registered office and regionsCompanies House, plus the firm’s own statement
Schemes and registersPublic record, or labelled “stated”
Claimed or unclaimedWhether the firm has confirmed its details with us
Listing last updatedDate

What a listing is not

It is not a recommendation, a prequalification or a sign that a firm is on any framework. It is not a credit check. It is a dated, checkable description of a real company. Anyone buying infrastructure work should still run their own due diligence.

Want to be removed, or corrected?

Email hello@whito.co.uk. We correct facts against the source, free, and we will remove a listing on request without asking why.

Method and limits

Method. Each firm is looked up by name at Companies House. We record the company number, status, incorporation date, SIC codes and registered office on the date of the check. Work examples come from the firm’s own site, published contract awards or regulator records, and are linked.

Limits. A Companies House match confirms that a company exists and is active. It says nothing about the quality of its work, its insurance or its finances. SIC codes are chosen by the company and can be broad. Public contract awards do not cover private work, so some firms will look smaller here than they are. Counts on this page are updated when listings are added, not in real time.

List your firm free →

Free to list, free to claim, and paying cannot move a listing.

Sources, each read on 23 September 2026