ET Top 50 2025

THE TOP

50

ELECTRICAL CONTRACTORS REPORT 2025

IN ASSOCIATION WITH:

T502025.indd 1

20 years of protecting your vital electrical systems 25/11/2025 17:00:00

14:21:14

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

A SECTOR ON THE MOVE

Navigating growth in a changing landscape

E

very year, the Top 50 Electrical Contractors report gives us a snapshot of where the industry is heading, and this year’s list tells a story of a sector that is anything but static.

Growth, change, and a fair bit of reshuffling define the 2025 results, with several contractors making big leaps thanks to acquisitions, expanding workloads, and the continued boom in data centres and energy-related projects.

One of the standout themes this year is momentum. Even though the top 50 as a whole delivered steady turnover growth, the top of the table saw dramatic movement, with a handful of companies posting especially strong results. Acquisitions played a noticeable role here, bringing new opportunities and sizeable project backlogs into the mix.

Profitability has also improved across much of the list. More businesses returned positive figures this year, and many saw stronger profit growth than we’ve typically seen in recent editions of

LISA PEAKE EDITOR, ELECTRICAL TIMES

the report. It’s a reminder that, even in a market shaped by shifting regulations and economic pressure, contractors are still finding ways to strengthen their positions.

We also saw higher profit per employee and improved return on sales among the top performers, hinting at greater efficiency and a more confident sector overall. With office construction gaining pace again and continued demand from energy, housing, and data infrastructure, the outlook remains upbeat. There’s a sense that the industry is adjusting well to new legislation, new expectations, and the changing shape of the built environment.

As always, this year’s Top 50 highlights not only the numbers but the wider direction of travel. The electrical contracting sector continues to show resilience, adaptability, and an ability to make the most of the opportunities in front of it — and that’s reflected clearly in the pages that follow.

GROWTH IN PROFIT RANK

TRADING NAME

PREVIOUS PRE-TAX PROFIT (£‘000)

MOVEMENT IN PRE-TAX PROFIT (£‘000)

RANK

9,370 5,277

345 1,261

9,025 4,016

26 27 28 29 30 31 32 33 34 35

CBES Limited The Castle Building Services Gratte Brothers Limited Stothers (M. & E.) Limited Carter Synergy Limited Premier Electrics Limited Irwin M&E Limited Skanska Rashleigh Weatherfoil Ltd Purdy Contracts Limited Emcor Group (UK) Plc

36 37 38 39 40 41 42 43 44 45 46 47 48

Vaughan Engineering Group Limited HF Group Limited P.I.P. Electrics Limited Atalian Servest Amk Limited Lorne Stewart Plc Derry Building Services Limited Clarkson Evans Limited Equans FM Limited Integral Uk Limited Enerveo Limited LJJ Ltd Dalkia Group Limited Mace Construct Specialist Services

49

Renelec Limited

-69

576

-645

50

FES Ltd

315

-776

1,090

LATEST PRE-TAX PROFIT (£‘000)

1 2

Halsall Electrical Limited Dalkia Operations Limited

3

DMG Engineering Limited

5,184

1,355

3,830

4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

AVK/SEG (UK) Limited Systems adi Group Limited Dornan Engineering Services Limited Halsion Limited Bancroft Limited Carmel (Group) Limited John Turner Construction Group Ltd The James Mercer Group Limited Quartzelec Ltd Dodd Group Limited Essex Services Group Limited The Barnes Group Limited NG Bailey Group Limited SES (Engineering Services) Limited Gloster MEP Limited

23,891 2,637 3,379 4,669 3,913 1,137 4,850 3,632 9,124 6,681 7,015 5,472 17,700 9,305 3,889

7,429 866 1,212 1,758 1,501 511 2,335 1,882 4,757 3,537 3,860 3,172 10,700 5,807 2,643

16,462 1,771 2,167 2,911 2,411 626 2,515 1,750 4,367 3,144 3,155 2,300 7,000 3,498 1,246

19 20 21 22 23 24 25

Phoenix Me Limited Actemium UK Limited Whitehead Building Services Limited Munro Building Services Limited Wingate Electrical Plc Tilbury Douglas Engineering Limited EJ Parker Technical Services

10,671 4,515 1,383 2,647 7,446 4,477 8,103

7,402 3,161 973 1,897 5,506 3,564 6,495

3,269 1,354 410 749 1,941 913 1,608

TRADING NAME

PREVIOUS PRE-TAX PROFIT (£‘000)

MOVEMENT IN PRE-TAX PROFIT (£‘000)

5,282 4,218 2,669 2,751 1,190 9,772 4,964 17,062 3,027 21,054

4,631 3,806 2,500 2,581 1,130 9,340 4,900 18,238 3,343 24,012

652 411 169 170 60 433 65 -1,176 -316 -2,958

240 610 4,241 -12,075 -1,643 1,783 1,386 1,944 -8,784 -1,700 11 312 -263

291 763 5,359 -15,881 -2,398 2,761 2,829 4,293 -31,687 -10,200 130 21,503 4,364

-50 -153 -1,118 3,806 755 -978 -1,442 -2,349 22,903 8,500 -119 -21,191 -4,627

Halsall Electrical Limited have hit the top highest profit growth for this year showing a remarkable 2,618 per cent increase in profit, a surprising recovery since last year’s profit loss. Dalkia Operation Limited with a profit growth of 318 per cent and DMG Engineering Limited with 283 per cent, are in second and third place respectively. This growth may be related to their involvement in the emerging energy sector. Compared to last year, where only 10 companies showed 50 per cent growth, this year, 16 companies show profit growth, with a combined average of 145 per cent (excluding the first-place contender as it is an outlier on this data).

There is a comparative higher number of companies achieving a higher profit growth level with more than 30 companies showing some manner of growth this year.

02

T502025.indd 2

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

25/11/2025 17:00:02

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

PROTECTING WHAT MATTERS MOST

K

eeping your electrical systems and essential technology safe is what we’re all about. At Surge Protection Devices Ltd, we’re proud to be the UK’s go-to team for lightning and surge protection.

With almost twenty years under our belts, we’ve solved all kinds of tricky problems, and in the past seven years, our experience matters more than ever, especially since the UK’s BS7671 wiring rules started calling for extra surge protection in our installations.

Trusted worldwide You will fi nd our surge protection devices just about everywhere— military bases, historic landmarks, factories, and family homes.

These devices are built to protect your electrical setup from sudden surges and lightning strikes. Nowadays, with everything from smart fridges to smart phones running on sensitive electronics, reliable surge protection is critical for keeping electrical installations safe and running smoothly.

All about safety We’re not just about making and selling products—we care about the safety and reliability of the entire electrical industry. Our Technical Director, Kirsty Johnson MIET, brings her expertise to the British Standards Wiring Regulations committee, focusing on lightning and surge protection. We are dedicated to making sure our industry sticks to the highest safety standards, which is why we were thrilled to be announced as the Innovation & Excellence Awards – Electrical Safety Specialists of the Year 2025!

Sharing knowledge We love helping everyone in the electrical fi eld get better at what they do. That is why we don’t just offer top-quality surge protection devices—we also give away free, indepth CPD training. Whether you’re part of a big-name consultancy or you’re just starting out as an apprentice, we’re here to share valuable technical know-how with you, explained in a way that makes surge protection easy to understand and easy to apply to your electrical installation, no matter how complicated the infrastructure may seem.

Raising the bar The electrical world is always changing and absolutely crucial, with safety always in the spotlight. As top-notch electrical design becomes more important for every kind of infrastructure, and as we work towards Net Zero goals in renewables, Surge Protection Devices Ltd is here to help. We’re not just delivering great products—we’re here with outstanding support and expertise, pushing safety standards higher for everyone.

What’s next?

Here at Surge Protection Devices, we are entering in to our 20th year in business in 2026, which is a massive milestone. As such, you will see us out and about celebrating with the electrical industry that has helped us grow. If you see any of the team out in 2026, please come and say hello!

If we can be of any help with any aspect of surge protection, feel free to get in touch via info@surgedevices.co.uk or 01484 851 747.

THE TOP 50 ELECTRICAL CONTRACTORS 2025

T

he Top 50 Electrical Contractors is analysed each year using a previously agreed pool of 60 contractors, to allow annual comparisons. This list is updated periodically to allow for new entrants into the data set.

Providing an overview of the performance of the market in this context is challenging, as the table includes different annual reporting periods and, in some cases, covers activities other than electrical contracting.

The recent analysis of turnover, profit growth, profit per employee, and return on sales within the electrical contracting sector shows significant advancements and shifts in performance reflective of mergers and acquisitions reported recently for those same companies.

Turnover growth reached an impressive average of 77 per cent among the top

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

T502025.indd 3

10 companies, with the highest performer showing a remarkable increase of 183 per cent, an average that should be carefully appraised as it is the likely result of acquisition of the number one ranker by an American company, who has a heavy backlog or projects (among them data centres) and plans for expansion. The overall top 50 companies maintained an 18 per cent average turnover growth. This growth balance indicates consistent opportunities within the market.

Further supporting this optimistic scenario, profit per employee across the top 50 companies averaged at 16 per cent, with fewer companies reporting negative figures since last year. The return on sales also highlighted strong performance, with the average for the top 10 being 11.16 per cent, alongside a corresponding increase among the top 50.

Lastly, more than just the shifts in rank, the top 35 profit rank averaged £6,932 million, an increase in last year and one more factor to encourage further investment in the sector.

The continued effects of office construction gaining momentum along with key sectors such as energy and data warehouses severely contributing to growth in the sector have influenced this year’s observed results. The market is estimated to continue to grow from 2025 to 2026 largely due to the pressures coming from new legislation regarding safety standards requiring remodelling of existing buildings and the government mandate for new house building.

The sector’s resilience and adaptability in face of recent challenges underscores a promising outlook for the coming years.

03

25/11/2025 17:00:04

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

YOUR GUIDE TO SPDS UNDER BS 7671

B

y this point, I should imagine that you are quite familiar with the term SPD (surge protection device) but there are still so many questions surrounding the use and application of surge protection devices, below details an introduction to what type of device is needed and when surge protection is required under BS7671.

For all other circumstances, a type 2 device will be sufficient to provide adequate protection for distribution boards.

Where protection against overvoltages is required for specific equipment, a type 3 device may be used to provide protection.

When are SPDs required Protection against transient overvoltages shall be provided where the consequence caused by overvoltage could:

What to install There are three types of SPDs depending on what you want to protect.

If you are looking to protect a distribution board or consumer unit, it will be a type 1 or type 2 SPD. If you wanted to protect a specific piece of equipment, such as a fuse spur or single socket, it would be a type 3.

A Type 1 device would only be required where there is an external lightning protection system or the installation has an overhead supply

i. Result in serious injury to, or loss of life ii. Deleted by Corrigendum May 2023 iii. Result in significant financial loss or data loss For all other cases, SPDs shall be fitted to protect against transient overvoltages, unless the installation’s owner declines such protection

GROWTH IN TURNOVER RANK

TRADING NAME

LATEST TURNOVER (£‘000)

PREVIOUS MOVEMENT RANK TURNOVER IN T/O (£‘000) (£'000)

TRADING NAME

LATEST PREVIOUS MOVEMENT IN T/O TURNOVER TURNOVER (£‘000) (£‘000) (£‘000)

Gloster MEP Limited DMG Engineering Limited Premier Electrics Limited EJ Parker Technical Services Stothers (M. & E.) Limited Gratte Brothers Limited CBES Limited The Barnes Group Limited Dalkia Group Limited Clarkson Evans Limited Atalian Servest Amk Limited

54,172 50,144 52,355 85,236 62,030 226,679 183,351 101,286 608,993 69,236 232,249

50,755 47,221 49,530 80,808 59,111 219,642 178,625 100,701 607,215 70,227 237,586

3,417 2,924 2,825 4,428 2,920 7,037 4,726 585 1,778 -990 -5,337

38 39 40 41 42 43 44 45 46 47 48 49

Mace Construct Specialist Services Emcor Group (UK) Plc Purdy Contracts Limited Systems adi Group Limited HF Group Limited Irwin M&E Limited Renelec Limited Lorne Stewart Plc Enerveo Limited Skanska Rashleigh Weatherfoil Ltd Integral Uk Limited Equans FM Limited Halsall Electrical Limited

69,897 332,980 49,507 130,071 43,665 53,184 54,481 101,566 218,400 247,050 293,603 104,672 53,204

73,563 350,941 53,118 143,319 48,368 58,944 61,876 118,745 256,700 296,640 362,399 131,325 70,407

-3,666 -17,961 -3,611 -13,248 -4,703 -5,760 -7,394 -17,179 -38,300 -49,590 -68,796 -26,653 -17,203

50

Dalkia Operations Limited

109,412

146,019

-36,607

1 2 3 4 5 6 7 8 9 10

Dornan Engineering Services Ltd AVK/SEG (UK) Limited The Castle Building Services Halsion Limited Phoenix Me Limited SES (Engineering Services) Ltd Munro Building Services Limited Vaughan Engineering Group Ltd P.I.P. Electrics Limited Carmel (Group) Limited

222,582 325,851 52,792 74,131 295,275 463,739 53,824 46,380 91,339 41,612

78,715 141,927 27,425 41,232 170,175 298,602 37,940 33,346 66,324 30,368

143,866 183,924 25,367 32,899 125,100 165,137 15,884 13,034 25,014 11,244

11 12

Whitehead Building Services Ltd John Turner Construction Group

58,670 101,297

45,283 79,900

26 27 28 29 30 31 32 33 34 35 13,387 36 21,397 37

13 14 15 16 17 18 19 20 21 22 23 24 25

LJJ Ltd Essex Services Group Limited Actemium UK Limited Derry Building Services Limited The James Mercer Group Limited Dodd Group Limited Quartzelec Ltd Bancroft Limited Wingate Electrical Plc FES Ltd Tilbury Douglas Engineering Ltd Carter Synergy Limited NG Bailey Group Limited

58,689 207,019 52,048 84,311 47,128 249,436 88,593 69,592 65,073 119,080 100,963 74,494 661,700

46,563 167,340 42,083 69,335 38,867 206,744 73,879 59,617 56,294 103,108 89,006 67,448 600,100

12,126 39,679 9,965 14,975 8,261 42,692 14,714 9,976 8,778 15,972 11,957 7,046 61,600

Dornan Engineering Services Limited has had an outstanding turnover this year showing a turnover growth of 183 per cent, a likely result of its acquisition by an American construction company. Among the top 10 companies, the average turnover growth reached 77 per cent. This average might be slightly inflated by our first place taker as growth from 4th to 10th place only ranges between 80 per cent to 37 per cent. But still, a great reflection of rising opportunities within this sector as the overall average for the top 50 this year has maintained a similar score to last year (18 per cent growth).

04

T502025.indd 4

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

25/11/2025 17:00:06

T502025.indd 5

25/11/2025 17:00:07

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

and wishes to accept the risk of damage to both wiring and equipment as tolerable.

The requirement to install SPDs where the consequences could result in serious injury to, or loss of human life is the most onerous requirement. This will mean that any distribution board supplying electrical equipment that is installed to protect life or prevent injury will require an SPD. Indent three is similar to the previous requirement where an SPD should be installed where commercial or industrial activity could be interrupted, the requirement now is that an SPD shall be provided where the consequence caused by overvoltage could result in significant financial or data loss.

The basic position of section 443 is now that SPDs shall be installed. In practical terms, most installations will have distribution boards that require surge protection due to the indents above, so it would only be distribution boards that did not require surge protection, as no circuits outlined in regulation 443.4.1 were

present. Then a discussion is encouraged between the electrical designer and the client to ensure that no unacceptable losses occur from overvoltage, while also considering the requirements to protect against switching overvoltages from regulation 443.4.2.

Something important to remember is that if the building has an external lightning protection system, then the requirements of BS EN 62305 apply, which means that a Type 1 SPD is a requirement in these cases and BS 7671 do not apply. Where the building has an external lightning protection system, a Type 1 SPD will be required on the main incomer and any distribution boards supplying external circuits.

I hope this article has provided some guidance on the requirements from BS 7671:2018, if you have any further questions, please do not hesitate to get in touch.

If you wish to discuss this topic further, or want to know more about the use of SPD’s, contact the surge protection experts on 01484 851747, or email us at info@surgedevices.co.uk.

PROFIT PER EMPLOYEE RANK

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

TRADING NAME

AVK/SEG (UK) Limited Halsall Electrical Limited Halsion Limited Gloster MEP Limited P.I.P. Electrics Limited The Castle Building Services Bancroft Limited EJ Parker Technical Services Stothers (M. & E.) Limited The Barnes Group Limited Phoenix Me Limited Skanska Rashleigh Weatherfoil Ltd Wingate Electrical Plc Essex Services Group Limited John Turner Construction Group Ltd Tilbury Douglas Engineering Limited The James Mercer Group Limited Irwin M&E Limited Quartzelec Ltd Purdy Contracts Limited Munro Building Services Limited Gratte Brothers Limited Dornan Engineering Services Limited Carmel (Group) Limited SES (Engineering Services) Limited

LATEST PRE-TAX PROFIT (£‘000)

LATEST NO. OF STAFF

PROFIT RANK PER EMPLOYEE

23,891 9,370 4,669 3,889 4,241 4,218 3,913 8,103 2,751 5,472 10,671 17,062 7,446 7,015 4,850 4,477 3,632 4,964 9,124 3,027 2,647 2,669 3,379 1,137 9,305

191 108 89 97 107 115 117 308 107 214 420 677 299 285 232 233 191 291 593 198 179 191 276 122 1,228

125 87 52 40 40 37 33 26 26 26 25 25 25 25 21 19 19 17 15 15 15 14 12 9 8

TRADING NAME

LATEST PRE-TAX PROFIT (£‘000)

LATEST NO. OF STAFF

PROFIT PER EMPLOYEE

26 27 28 29 30 31 32 33 34 35 36

Emcor Group (UK) Plc Derry Building Services Limited Whitehead Building Services Limited CBES Limited Dodd Group Limited Systems adi Group Limited NG Bailey Group Limited Carter Synergy Limited Dalkia Operations Limited Equans FM Limited HF Group Limited

21,054 1,783 1,383 5,282 6,681 2,637 17,700 1,190 5,277 1,944 610

3,009 259 215 845 1,109 494 3,411 292 1,818 797 333

7 7 6 6 6 5 5 4 3 2 2

37

Clarkson Evans Limited

1,386

762

2

38 39

Vaughan Engineering Group Limited LJJ Ltd

240 11

174 103

1 0

40 41 42 43 44 45 46 47 48 49 50

Dalkia Group Limited FES Ltd Mace Construct Specialist Services Premier Electrics Limited Actemium UK Limited DMG Engineering Limited Renelec Limited Enerveo Limited Lorne Stewart Plc Integral Uk Limited Atalian Servest Amk Limited

312 315 -263 9,772 4,515 5,184 -69 -1,700 -1,643 -8,784 -12,075

4,064 0 0 79 257 71 228 1,097 563 1,690 1,359

0 0 0 0 0 0 0 -2 -3 -5 -9

This year, AVK/SEG (UK) Limited is leading on profit per employee showing a £125k, further reinforcing their performance on other categories. Halsall Electrical Limited with 87 per cent and Halsion Limited with 52 per cent follow up in second and third respectively. The top 10 electrical contractors averaged approximately 49 per cent profit (including the first place contender) showing an increase since last year’s figures and a positive outlook for the sector. Among the top 50 companies, the average profit per employee stands at 16 per cent, marking an increase and a positive trend compared to last year, as fewer companies are reporting negative profit per employee.

06

T502025.indd 6

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

25/11/2025 17:00:08

T502025.indd 7

25/11/2025 17:00:09

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

SURGE PROTECTION IN SOLAR PV SHOULDN’T BE AN AFTERTHOUGHT The number of solar PV installations is on the rise, but one of the aspects of PV system design that is often overlooked is surge protection. BS7671:2018 section 443.4, which gives the requirements for when surge protection shall be installed, covers both AC and DC installations, this is something that is often not considered when we consider where surge protection is required. In section seven for special locations, we also have regulation 712.443.101 states that where protection against transient overvoltage is required by section 443, such protection shall also be applied to the DC side of the PV installation. So, if the solar installation as on the roof of a building where the regulations in section 443 require SPD’s to be installed, SPDs also need to be installed on the DC side of the installation to protect the inverter.

Some inverters state that they include overvoltage protection. For an incorporated SPD to fulfil the requirements of the wiring regulations, the manufacturer must specify that it is installed on the DC side of the inverter, as this ensures that it is providing protection on the correct side of the inverter. There are quite a few inverters on the market

which say they have overvoltage protection included, when in actual fact, it is only providing protection on the AC side of the system. It must also state the type of SPD, the reason it is important for the type of SPD to be mentioned is that once a device is specified as a type it must conform to the product standard BS EN 61643-31 as some manufacturers incorporate individual varistors, which are not considered to be a complete surge protection device. If you are unsure and want to check the technical credibility of an inverter, I would advise you to request a certificate of conformity, which will list the standards that the equipment conforms to.

Another consideration is that the inverter will only ever include a Type 2 surge protection device, so if the building has an external lightning protection system, the installation will always require the use of external Type 1 SPDs to conform to BS EN 62305, as the cables will cross between the lightning protection zones.

When a PV system is installed on a building with an external lightning protection system (LPS) the PV system should be separated from all parts of the LPS in accordance with BS EN 62305-3. This is referred

RETURN ON SALES TRADING NAME

LATEST TURNOVER (£’000)

PREVIOUS PRE-TAX PROFIT (£‘000)

RETURN ON SALES (%)

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Premier Electrics Limited Halsall Electrical Limited Wingate Electrical Plc DMG Engineering Limited Quartzelec Ltd EJ Parker Technical Services Irwin M&E Limited Actemium UK Limited The Castle Building Services The James Mercer Group Limited AVK/SEG (UK) Limited Gloster MEP Limited Skanska Rashleigh Weatherfoil Ltd Emcor Group (UK) Plc

52,355 53,204 65,073 50,144 88,593 85,236 53,184 52,048 52,792 47,128 325,851 54,172 247,050 332,980

9,772 9,370 7,446 5,184 9,124 8,103 4,964 4,515 4,218 3,632 23,891 3,889 17,062 21,054

18.67 17.61 11.44 10.34 10.30 9.51 9.33 8.67 7.99 7.71 7.33 7.18 6.91 6.32

15 16 17 18 19

Halsion Limited Purdy Contracts Limited Bancroft Limited The Barnes Group Limited Munro Building Services Limited

74,131 49,507 69,592 101,286 53,824

4,669 3,027 3,913 5,472 2,647

6.30 6.12 5.62 5.40 4.92

20 21 22 23 24 25

Dalkia Operations Limited John Turner Construction Group Ltd P.I.P. Electrics Limited Stothers (M. & E.) Limited Tilbury Douglas Engineering Limited Phoenix Me Limited

109,412 101,297 91,339 62,030 100,963 295,275

5,277 4,850 4,241 2,751 4,477 10,671

4.82 4.79 4.64 4.43 4.43 3.61

RANK

TRADING NAME

LATEST TURNOVER (£’000)

PREVIOUS PRE-TAX PROFIT (£‘000)

RETURN ON SALES (%)

26 27 28 29 30 31 32 33 34

Essex Services Group Limited CBES Limited Carmel (Group) Limited Dodd Group Limited NG Bailey Group Limited Whitehead Building Services Limited Derry Building Services Limited Systems adi Group Limited SES (Engineering Services) Limited

207,019 183,351 41,612 249,436 661,700 58,670 84,311 130,071 463,739

7,015 5,282 1,137 6,681 17,700 1,383 1,783 2,637 9,305

3.39 2.88 2.73 2.68 2.67 2.36 2.11 2.03 2.01

35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

Clarkson Evans Limited Equans FM Limited Carter Synergy Limited Dornan Engineering Services Limited HF Group Limited Gratte Brothers Limited Vaughan Engineering Group Limited FES Ltd Dalkia Group Limited LJJ Ltd Renelec Limited Mace Construct Specialist Services Enerveo Limited Lorne Stewart Plc Integral Uk Limited Atalian Servest Amk Limited

69,236 104,672 74,494 222,582 43,665 226,679 46,380 119,080 608,993 58,689 54,481 69,897 218,400 101,566 293,603 232,249

1,386 1,944 1,190 3,379 610 2,669 240 315 312 11 -69 -263 -1,700 -1,643 -8,784 -12,075

2.00 1.86 1.60 1.52 1.40 1.18 0.52 0.26 0.05 0.02 -0.13 -0.38 -0.78 -1.62 -2.99 -5.20

RANK

The average return on sales across the top 10 is 11.16 per cent and across the top 50 contractors is 4.33 per cent, an increase versus last year. The top three performers show a return on sales of 18,67 per cent (Premier Electrics Limited), 17,61 per cent (Halsall Electrical Limited) and 11.44 per cent (Wingate Electrical Plc) DMG Engineering Limited and Quartzelec Ltd are two noteworthy entrants as they rise to notoriety versus last year with a 10.34 per cent and 10.30 per cent return on sales respectively. This year is filled with new names and is swayed by some transitions in the market seen by new growth, and some mergers and acquisitions.

08

T502025.indd 8

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

25/11/2025 17:00:10

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

to as the separation distance. This distance must be adhered to between the LPS and any metal work to ensure that no dangerous arcing can occur. If the separation distance is not met, then the metal work must be bonded to the LPS, therefore becoming part of the lightning protection system. More information on separation distances can be found in BS EN 62305, but it is important to note that the separation distance depends on different parts of the lightning protection risk assessment carried out for each individual building, and therefore will be included in the LPS paperwork, if available. This calculation should only be carried out by someone with experience in the lightning protection field. If the separation distance is not met and therefore the PV system has become part of the LPS then the SPD required will need to be a Type 1, as mentioned above, this will always be external from the inverter.

From experience, there are not many installations that correctly conform to these separation distances, so as a general rule, if the building has an LPS a Type 1 SPD should be installed on the DC side of the installation. For all other PV systems, a Type 2 SPD will provide adequate protection.

Although the SPDs are still defined as Type 1 and Type 2 devices, they are different to the SPDs we see used on the AC electrical systems and only SPDs that are designed for the specific use on the

DC side of a solar PV installation should be used.

This is due to the continual loading and higher voltages of PV systems. The devices designed for the use on the DC side of PV systems are clearly marked with the PV symbol, as per the requirements in BS EN 61643-31. Also, they look slightly different, with the live and neutral terminals being replaced by a positive and negative terminal.

Selection of a PV SPD is quite simple. From the above, you should know what type of SPD you need. The only other information needed is the operating capacity of the inverter, which is usually 600V or 1,000V. There are some specialist systems which are different, and there are devices available for those too, but for simplicity we will stick with the 600V & 1,000V options. That gives four options of devices.

Now we have the correct device selected, we can move on to installation. As with our AC SPDs, our DC SPDs are installed in parallel with the string. Usually a DC isolator would be used. DC SPDs should be installed one per string to provide protection, although in some situations it may be possible to protect multiple strings with one SPD, depending on the installation design.

For more information, call 01484 851747, or email us at info@ surgedevices.co.uk.

PROFIT RANK TRADING NAME

LATEST PRE-TAX PROFIT (£‘000)

1 2 3 4 5 6 7 8

AVK/SEG (UK) Limited Emcor Group (UK) Plc NG Bailey Group Limited Skanska Rashleigh Weatherfoil Limited Phoenix Me Limited Premier Electrics Limited Halsall Electrical Limited SES (Engineering Services) Limited

23,891 21,054 17,700 17,062 10,671 9,772 9,370 9,305

9 10 11 12 13 14

Quartzelec Ltd EJ Parker Technical Services Wingate Electrical Plc Essex Services Group Limited Dodd Group Limited The Barnes Group Limited

9,124 8,103 7,446 7,015 6,681 5,472

15 16 17 18 19 20 21 22 23 24 25

CBES Limited Dalkia Operations Limited DMG Engineering Limited Irwin M&E Limited John Turner Construction Group Ltd Halsion Limited Actemium UK Limited Tilbury Douglas Engineering Limited P.I.P. Electrics Limited The Castle Building Services Bancroft Limited

5,282 5,277 5,184 4,964 4,850 4,669 4,515 4,477 4,241 4,218 3,913

RANK

RANK

26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

TRADING NAME

LATEST PRE-TAX PROFIT (£‘000)

Gloster MEP Limited The James Mercer Group Limited Dornan Engineering Services Limited Purdy Contracts Limited Stothers (M. & E.) Limited Gratte Brothers Limited Munro Building Services Limited Systems adi Group Limited Equans FM Limited Derry Building Services Limited Clarkson Evans Limited Whitehead Building Services Limited Carter Synergy Limited Carmel (Group) Limited HF Group Limited FES Ltd Dalkia Group Limited Vaughan Engineering Group Limited LJJ Ltd Renelec Limited Mace Construct Specialist Services Ltd Lorne Stewart Plc Enerveo Limited Integral Uk Limited Atalian Servest Amk Limited

3,889 3,632 3,379 3,027 2,751 2,669 2,647 2,637 1,944 1,783 1,386 1,383 1,190 1,137 610 315 312 240 11 -69 -263 -1,643 -1,700 -8,784 -12,075

AVK/SEG (UK) Limited is a top ranker once more on general profit rank, occupying the first place with £23,891 million in profit Emcor Group (UK) Plc occupies second place with £21,054 million in profit, falling from first place since last year, and it is followed by NG Bailey Group Limited in third place with £17,700 million in profit. The average pre-tax profit for the top 35 companies this year is approximately £6,932, reflecting an increase from last year and indicating ongoing sequential growth following a rise in the previous year as well.

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

T502025.indd 9

09

25/11/2025 17:00:12

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

THE TOP 50 MOVEMENT IN TURNOVER (£’000)

CHANGE IN TURNOVER (%)

600,100

61,600

10

607,215

1,778

0

463,739

298,602

165,137

55

Emcor Group (UK) Plc

332,980

350,941

-17,961

-5

141,927

183,924

130

LATEST TURNOVER

RANKING 2022

RANKING 2021

TRADING NAME

1

2

NG Bailey Group Limited

661,700

2

1

Dalkia Group Limited

608,993

3

9

SES (Engineering Services) Limited

4

4

PREVIOUS TURNOVER (£’000)

5

29

AVK/SEG (UK) Limited

325,851

6

11

Phoenix Me Limited

295,275

170,175

125,100

74

362,399

-68,796

-19

7

5

Integral Uk Limited

293,603

8

10

Dodd Group Limited

249,436

206,744

42,692

21

9

8

Skanska Rashleigh Weatherfoil Limited

247,050

296,640

-49,590

-17

10

7

Atalian Servest Amk Limited

232,249

237,586

-5,337

-2

11

21

Gratte Brothers Limited

226,679

219,642

7,037

3

12

41

Dornan Engineering Services Limited

222,582

78,715

143,866

183

13

6

Enerveo Limited

218,400

256,700

-38,300

-15

Essex Services Group Limited

207,019

167,340

39,679

24

CBES Limited

183,351

178,625

4,726

3

143,319

14 15

19 15

16

17

Systems adi Group Limited

130,071

-13,248

-9

17

18

FES Ltd

119,080

103,108

15,972

15

18

12

Dalkia Operations Limited

109,412

146,019

-36,607

-25

19

16

Equans FM Limited

104,672

131,325

-26,653

-20

20

13

Lorne Stewart Plc

101,566

118,745

-17,179

-14

21

24

John Turner Construction Group Ltd

101,297

79,900

21,397

27

22

20

The Barnes Group Limited

101,286

100,701

585

1

89,006

11,957

13

23

30

Tilbury Douglas Engineering Limited

100,963

24

45

P.I.P. Electrics Limited

91,339

66,324

25,014

38

Quartzelec Ltd

88,593

73,879

14,714

20

80,808

4,428

5

14,975

22

25

27

26

25

EJ Parker Technical Services

85,236

27

32

Derry Building Services Limited

84,311

69,335

28

34

Carter Synergy Limited

74,494

67,448

7,046

10

29

39

Halsion Limited

74,131

41,232

32,899

80

30

23

Mace Construct Specialist Services Limited

69,897

73,563

-3,666

-5

31

37

Bancroft Limited

69,592

59,617

9,976

17

32

28

Clarkson Evans Limited

69,236

70,227

-990

-1

56,294

8,778

16

33

40

Wingate Electrical Plc

65,073

34

38

Stothers (M. & E.) Limited

62,030

59,111

2,920

5

46,563

12,126

26

35

31

LJJ Ltd

58,689

36

0

Whitehead Building Services Limited

58,670

45,283

13,387

30

37

33

Renelec Limited

54,481

61,876

-7,394

-12

38

42

Gloster MEP Limited

54,172

50,755

3,417

7

39

43

Munro Building Services Limited

53,824

37,940

15,884

42

40

22

Halsall Electrical Limited

53,204

70,407

-17,203

-24

41

48

Irwin M&E Limited

53,184

58,944

-5,760

-10

The Castle Building Services

52,792

27,425

25,367

92

Premier Electrics Limited

52,355

49,530

2,825

6

42,083

9,965

24

42 43

0 0

44

0

Actemium UK Limited

52,048

45

46

DMG Engineering Limited

50,144

47,221

2,924

6

46

36

Purdy Contracts Limited

49,507

53,118

-3,611

-7

47

0

The James Mercer Group Limited

47,128

38,867

8,261

21

48

0

Vaughan Engineering Group Limited

46,380

33,346

13,034

39

49

44

HF Group Limited

43,665

48,368

-4,703

-10

50

47

Carmel (Group) Limited

41,612

30,368

11,244

37

10

T502025.indd 10

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

25/11/2025 17:00:12

NGE IN NOVER

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025 PROFIT (£’000)

LATEST PRE-TAX PROFIT (£’000)

PREVIOUS PRE-TAX PROFIT (£’000)

MOVEMENT IN PRE-TAX PROFIT (£’000)

CHANGE IN PRE-TAX PROFIT (%)

LATEST NO. OF EMPLOYEES

PREVIOUS NO. OF EMPLOYEES

PROFIT PER EMPLOYEE

RETURN ON SALES

17,700

10,700

7,000

65

3,411

3,216

5

2.7

312

21,503

-21,191

-99

4,064

4,019

0

0.1

9,305

5,807

3,498

60

1,228

960

8

2.0

24,012

-2,958

-12

3,009

3,241

7

6.3

222

191

175

125

7.3

44

420

373

25

3.6

21,054 23,891 10,671

7,429 7,402

16,462 3,269

-8,784

-31,687

22,903

-72

1,690

1,985

-5

-3.0

6,681

3,537

3,144

89

1,109

977

6

2.7

17,062

18,238

-1,176

-6

677

899

25

6.9

-12,075

-15,881

3,806

-24

1,359

1,279

-9

-5.2

2,669

2,500

169

7

191

179

14

1.2

3,379

1,212

2,167

179

276

215

12

1.5

-1,700

-10,200

8,500

-83

1,097

1,444

-2

-0.8

7,015

3,860

3,155

82

285

248

25

3.4

803

6

2.9

5,282

4,631

652

14

845

2,637

866

1,771

205

494

474

5

2.0

315

-776

1,090

-141

0

0

n.a.

0.3

5,277

1,261

4,016

318

1,818

1,834

3

4.8

1,944

4,293

-2,349

-55

797

947

2

1.9

-1,643

-2,398

755

-31

563

565

-3

-1.6

4,850

2,335

2,515

108

232

233

21

4.8

5,472

3,172

2,300

73

214

208

26

5.4

3,564

913

26

233

224

19

4.4

-21

107

107

40

4.6 10.3

4,477 4,241

5,359

-1,118

9,124

4,757

4,367

92

593

562

15

8,103

6,495

1,608

25

308

334

26

9.5

1,783

2,761

-978

-35

259

241

7

2.1

1,190

1,130

60

5

292

306

4

1.6

4,669

1,758

2,911

166

89

87

52

6.3

-263

4,364

-4,627

-106

0

0

n.a.

-0.4

3,913

1,501

2,411

161

117

108

33

5.6

2,829

-1,442

-51

762

794

2

2.0 11.4

1,386 7,446

5,506

1,941

35

299

288

25

2,751

2,581

170

7

107

100

26

4.4

11

130

-119

-91

103

127

0

0.0

1,383

973

410

42

215

196

6

2.4

-69

576

-645

-112

228

235

0

-0.1

3,889

2,643

1,246

47

97

105

40

7.2

2,647

1,897

749

39

179

173

15

4.9

9,370

345

9,025

2,618

108

107

87

17.6

4,964

4,900

65

1

291

229

17

9.3

11

115

121

37

8.0

80

124

18.7

213

18

8.7

4,218

3,806

411

9,772

9,340

433

5

79

4,515

3,161

1,354

43

257

5,184

1,355

3,830

283

71

77

73

10.3

3,027

3,343

-316

-9

198

182

15

6.1

3,632

1,882

1,750

93

191

192

19

7.7

240

291

-50

-17

174

157

1

0.5

610

763

-153

-20

333

339

2

1.4

1,137

511

626

122

122

127

9

2.7

TOP 50 ELECTRICAL CONTRACTORS REPORT 2025

T502025.indd 11

11

25/11/2025 17:00:13

T502025.indd 12

25/11/2025 17:00:14