Company lists · Data refreshed September 2026

Top 25 Electrical system design companies based in the United Kingdom

Name: Electrical system design companies based in the United Kingdom
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 19, 2026 2,948 companies tracked

RevenueBase identified 2,948 electrical system design companies headquartered in the United Kingdom as of September 2026 and tracks 19,459 professional contacts across them, including 6,912 with verified work emails. London is the largest hub.

This list covers electrical system design companies headquartered in the United Kingdom, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 19, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 19, 2026 86% judged on-target in blind review

2,948Companies

19,459Contacts tracked

6,912Verified emails

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The 25 largest electrical system design companies based in the United Kingdom

Ranked by team size

Top 25 of 2,948 electrical system design companies based in the United Kingdom, ranked by team size, largest first. Data refreshed Sep 19, 2026. RevenueBase Smart Search rates how each company's information relates to electrical system design companies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Hoare LEA	Partial evidence	London, United KingdomHQ checked Sep 19, 2026	501-1,000	1,103 contacts →
	Partial evidence “We are an award-winning engineering consultancy with a creative team of engineers, designers, and technical specialists.” Source: RevenueBase Database · checked Sep 19, 2026
2	Z-Tech Control Systems LTD	Indirect evidence	Swavesey, United KingdomHQ checked Sep 19, 2026	201-500	156 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 19, 2026
3	Asee Group	Partial evidence	Newry, United KingdomHQ checked Sep 19, 2026	51-200	151 contacts →
	Partial evidence “ASEE Group is a leader in mechanical and electrical engineering, specialising in generator integration and full-service installations for 45+ years.” Source: RevenueBase Database · checked Sep 19, 2026
4	Cilantro Engineering UK Limited	Strong evidence	London, United KingdomHQ checked Sep 19, 2026	201-500	123 contacts →
	Strong evidence “Cilantro Engineering is a multi-discipline Building Services Contractor offering a vast range of Mechanical and Electrical Design & Installation services.” Source: RevenueBase Database · checked Sep 19, 2026
5	AF Switchgear	Indirect evidence	Sutton-in-ashfield, United KingdomHQ checked Sep 19, 2026	201-500	117 contacts →
	Indirect evidence “AF Switchgear is one of the UK's largest switchgear manufacturers and set the standard for LV Switchgear and Power Distribution.” Source: RevenueBase Database · checked Sep 19, 2026
6	LJJ LTD	Partial evidence	Stockton On Tees, United KingdomHQ checked Sep 19, 2026	201-500	114 contacts →
	Partial evidence “LJJ formed in 2001 as a private limited company and is a multi-disciplined organisation capable of completing major mechanical, electrical and public health service contracts in a…” Source: RevenueBase Database · checked Sep 19, 2026
7	Darke & Taylor LTD	Strong evidence	Oxfordshire, United KingdomHQ checked Sep 19, 2026	51-200	112 contacts →
	Strong evidence “Our mission is to excel in the design, installation and maintenance of the electro-technical systems that connect to create fit for purpose building environments.” Source: RevenueBase Database · checked Sep 19, 2026
8	G & A Barnie Group LTD	Indirect evidence	Inverness, United KingdomHQ checked Sep 19, 2026	201-500	109 contacts →
	Indirect evidence “Premier quality workmanship and personal attention are characteristics of G&A Barnie.” Source: RevenueBase Database · checked Sep 19, 2026
9	Alan Wood & Partners	Indirect evidence	Hull, United KingdomHQ checked Sep 19, 2026	51-200	106 contacts →
	Indirect evidence “Established in 1968 as a firm of Consulting Civil & Structural Engineers Alan Wood & Partners now have 7 offices in the UK.” Source: RevenueBase Database · checked Sep 19, 2026
10	Rock Power Connections LTD	Partial evidence	Bromsgrove, United KingdomHQ checked Sep 19, 2026	51-200	105 contacts →
	Partial evidence “Rock Power Connections are experts in electrical connections with a proven track record of quality and safety.” Source: RevenueBase Database · checked Sep 19, 2026
11	JCW Energy Services LTD	Indirect evidence	Melbourn, United KingdomHQ checked Sep 19, 2026	201-500	103 contacts →
	Indirect evidence “JCW Energy Services is a privately held SME business operating in the building services engineering sector throughout the UK.” Source: RevenueBase Database · checked Sep 19, 2026
12	Hulley And Kirkwood	Indirect evidence	Glasgow, United KingdomHQ checked Sep 19, 2026	51-200	98 contacts →
	Indirect evidence “We are an independent Building Services Consultancy providing national coverage.” Source: RevenueBase Database · checked Sep 19, 2026
13	Sinewave	Partial evidence	Swindon, United KingdomHQ checked Sep 19, 2026	51-200	96 contacts →
	Partial evidence “Sinewave are a specialist engineering company who provide High and Low voltage electrical services across the UK.” Source: RevenueBase Database · checked Sep 19, 2026
14	Services Design Solution SDS	Strong evidence	South West, United KingdomHQ checked Sep 19, 2026	51-200	87 contacts →
	Strong evidence “SDS is a forward-looking, dynamic construction consultancy specialising in the design of sustainable, mechanical and electrical engineering systems for buildings.” Source: RevenueBase Database · checked Sep 19, 2026
15	GTDS	Indirect evidence	Hill, United KingdomHQ checked Sep 19, 2026	51-200	82 contacts →
	Indirect evidence “GTDS was established in July 2004 to provide specialist installation and commissioning services to the major manufacturers, National Grid and the Distribution Network Operators…” Source: RevenueBase Database · checked Sep 19, 2026
16	Grant Walker Engineering	Strong evidence	London, United KingdomHQ checked Sep 19, 2026	51-200	81 contacts →
	Strong evidence “Grant Walker Engineering specialise in the complete installation of Electrical and Mechanical systems across all work sectors including quality office developments, commercial and…” Source: RevenueBase Database · checked Sep 19, 2026
17	AKD	Indirect evidence	Edinburgh, United KingdomHQ checked Sep 19, 2026	51-200	79 contacts →
	Indirect evidence “AKD’s clients get quick results, normally leading to reduced costs and gaining an improved service.” Source: RevenueBase Database · checked Sep 19, 2026
18	Global Substation Solutions LTD	Partial evidence	Hebburn, United KingdomHQ checked Sep 19, 2026	51-200	75 contacts →
	Partial evidence “Established in 2006, Global Substation Solutions Ltd (GSS) are a dynamic power system engineering company, providing turnkey project services to the UK and international…” Source: RevenueBase Database · checked Sep 19, 2026
19	AQ Wiring Systems Rockford	Strong evidence	Rendlesham, United KingdomHQ checked Sep 19, 2026	51-200	74 contacts →
	Strong evidence “AQ Wiring Systems Rockford designs and manufactures high-reliability electrical systems, cable assemblies, and electro-mechanical solutions for defence, aerospace, and advanced…” Source: RevenueBase Database · checked Sep 19, 2026
20	Delap & Waller	Partial evidence	Antrim /, United KingdomHQ checked Sep 19, 2026	51-200	73 contacts →
	Partial evidence “Delap & Waller Mechanical and Electrical Building Services Engineers was founded in 1911, and to this day we remain a leader in the field of Mechanical and Electrical Building…” Source: RevenueBase Database · checked Sep 19, 2026
21	RSE Control Systems Saftronics	Strong evidence	Leeds, United KingdomHQ checked Sep 19, 2026	51-200	68 contacts →
	Strong evidence “Established in 1979 and located in Leeds in a purpose built 2,400m² design, manufacturing and testing facility, Saftronics specialise in process control systems and LV…” Source: RevenueBase Database · checked Sep 19, 2026
22	DSSR	Partial evidence	Manchester, United KingdomHQ checked Sep 19, 2026	51-200	67 contacts →
	Partial evidence “DSSR is a forward-thinking, award-winning company of Consulting Engineers specialising in all aspects of Building Services and Sustainability design.” Source: RevenueBase Database · checked Sep 19, 2026
23	ETA Projects LTD	Indirect evidence	London, United KingdomHQ checked Sep 19, 2026	11-50	62 contacts →
	Indirect evidence “Chosen to deliver, trusted to care - for 30 years we’ve worked with clients across a diverse range of sectors to deliver safe and sustainable engineering solutions that prioritise…” Source: RevenueBase Database · checked Sep 19, 2026
24	CBG Consultants LTD	Indirect evidence	London, United KingdomHQ checked Sep 19, 2026	51-200	61 contacts →
	Indirect evidence “As an ambitious building services consultancy, at CBG Consultants we have a strong commitment to excellence.” Source: RevenueBase Database · checked Sep 19, 2026
25	Banyards	Strong evidence	London, United KingdomHQ checked Sep 19, 2026	51-200	58 contacts →
	Strong evidence “We are a specialist consultancy business delivering mechanical and electrical design and commissioning consultancy.” Source: RevenueBase Database · checked Sep 19, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: electrical system design companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names electrical system design companies.
Partial evidence: Its own public description names part of electrical system design companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name electrical system design companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 2,948 electrical system design companies based in the United Kingdom

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Electrical system design companies based in the United Kingdom at a glance

As of Sep 19, 2026

35.5%Verified-email coverage

6.6Average contacts per company

1-10Median size (employees)

7.2%Largest-city concentration · London

Sep 19, 2026Page data refreshed

Companies by employee count

1-10

1,704

11-50

1,001

51-200

167

201-500

501-1,000

1,001-5,000

10001+

Email recency for this list is measured worldwide rather than for United Kingdom, so it is reported there. Company counts and contact totals on this page are exact for United Kingdom, over 2,948 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among electrical system design companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in the United Kingdom whose own description of what they do matches “electrical system design companies”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names electrical system design companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among electrical system design companies, and records with no verified work email. Companies headquartered outside United Kingdom are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every listed company carries at least one verified work email, 6,912 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on September 19, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Electrical system design companies by metro

Electrical system design companies in London213
Electrical system design companies in Manchester52
Electrical system design companies in Nottingham39
Electrical system design companies in Glasgow38
Electrical system design companies in Bristol36
Electrical system design companies in Southampton29
Electrical system design companies in Birmingham28
Electrical system design companies in Leeds27
Electrical system design companies in Sheffield27

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names electrical system design companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many electrical system design companies are there based in the United Kingdom?

RevenueBase identified 2,948 electrical system design companies headquartered in the United Kingdom as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Hoare LEA, headquartered in London, tops this list with the largest team on record.

Which city has the most electrical system design companies?

London leads with 213 headquartered companies, followed by Manchester (52) and Nottingham (39).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 6,912 verified decision-maker contacts tracked across these 2,948 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 19, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.