UK electrical equipment: the multinationals book the turnover, the specialist makers keep the profit

About 191 UK electrical-equipment makers publish a full profit-and-loss, booking £6.9bn of combined turnover — switchgear, grid kit, control systems, fire detection, test instruments and the odd DJ deck. The headline of the map is a split that runs straight down the giants table: the biggest turnover lines belong to global groups’ UK arms, whose 1–3% margins are set by transfer pricing rather than the market, while the real profit pool sits one tier down with UK-based specialist manufacturers — generator controllers, grid sensors, electrical test gear — earning 20–50%; note that the ownership of several of the best of them already sits overseas. The electrification story (grid upgrades, EV infrastructure, data centres) shows up clearly in the growth lines; it just pays out in the mid-market, not at the multinationals’ UK plants. Figures are approximate — verify against a company’s own accounts before relying on any single number.

Read the giants table like a customs officer

Most of the biggest names here are not really competing in a UK market — they are the local limb of a global group, and their UK profit line is whatever the group’s transfer-pricing policy says it should be. Robert Bosch books £494M through its UK company for a 2% margin; Domino, the Cambridge coding-and-marking printer business owned by Brother, shows £4.6M on £359M; Eaton Electric — switchgear, exactly the kit the grid build-out needs — grew 21% and still shows a 2.3% margin. These are cost-plus and distribution economics, not a verdict on the businesses. A couple aren’t even manufacturers in any meaningful UK sense: AlphaTheta moves £158M of Pioneer DJ hardware through 78 people — a distribution hub — and Canon Europe is an imaging group’s European head-office entity that happens to land in this category.

…and 181 more, including Apollo Fire Detectors (£124.8M, £39.2M — fire detection, Halma group) and Canon Europe (£123.9M).

Two lines in that table deserve a second look. KLA Corporation UK’s £142M of profit on £368M — a 39% margin inside a US group structure — is the reverse of the cost-plus pattern and almost certainly reflects where the group chooses to recognise the value of UK-built semiconductor kit; treat it as group accounting, not a UK market signal (and note KLA’s UK company reports in US dollars — the sterling figures here are converted at an approximate period-average rate). And Anord Mardix is the purest demand read-out in the sector: it builds switchgear for data centres, and it grew turnover 17% while hiring 12% more people — 1,041 staff and climbing. That’s the electrification boom, visible in payroll. (Its data-centre customers are mapped in our data-centres report.)

The shape of the market

This is a healthy, mid-market-heavy industry. The centre of gravity is the £5–25M specialist maker — 92 companies, 82% profitable — and profitability rises with size: 83% in the £25–100M band, 94% above £100M. There is barely a struggling small tier on the map, partly because genuinely small workshops don’t publish full accounts, and partly because the survivors of this old industry tend to own a niche.

Where the money is: instruments, controls and detection

Set aside the multinationals’ cost-plus arms and the pattern in the best-run tier is unmistakable: the profits belong to companies that make the clever box, not the big box — controllers, sensors, test instruments and detection systems where the intellectual property is the product. One honesty note first: several of these specialists are themselves foreign-owned, so “one tier down” describes where they make things, not who owns them. Deep Sea Electronics — built in North Yorkshire, owned by US generator group Generac — turns £67.6M of generator control modules into £29.6M of pre-tax profit, a 43.7% margin even in a down year (turnover fell 17%). Megger Instruments, the Dover electrical test-equipment maker, runs at 31.6%. CRFS, a Cambridge radio-spectrum-monitoring specialist in the US Silvus group, posts a 51.2% margin and 41% growth. N.J. Froment, the manufacturing arm of US-owned Avtron Power Solutions, makes 35.9% building load banks and generator test kit with 93 people.

…and ten more £5–100M operators clearing 5%+, including Hochiki Europe (fire detection, 15.5%), CPI TMD Technologies (microwave tubes, 12.8%), RMSpumptools (downhole electrical tools for oil wells, 30.6%), CRFS (51.2% — and a live example of the acquisition thesis below: its US parent Silvus was bought by Motorola Solutions in August 2025) and SRL Traffic Systems (portable traffic signals, 20.4% — hire-fleet economics rather than pure manufacture).

Three caveats on this table. The Camlin group appears twice in the raw ranking — Camlin and Camlin Energy (£47.9M at 24.8%) are entities of the same Lisburn grid-monitoring business, so count it once. Emerson Process Management Distribution (£68.7M, 19.0%) is what its name says — a global group’s distribution arm — and is left out above. And fire detection’s strong showing (Apollo at 31%+, Advanced at 35.7%, both Halma-owned, plus Japanese-owned Hochiki) says as much about Halma’s famous acquisition discipline as about the UK market: the best British specialist makers tend to get bought, and these margins are why.

Growth, read with care

The growth table splits into three different stories, and only one of them is healthy demand.

Story one: the energy-transition cash burn. The top of the growth table is the venture tier of the electrification boom, growing fast and losing multiples of its revenue. ITM Power, the Sheffield hydrogen-electrolyser maker, appears twice — the listed group and its trading subsidiary both land on this map, so don’t add the two losses together; the group line is the real read-out: £26.0M of revenue against a £45.4M pre-tax loss — of which £13.1M is a one-off Linde settlement — on a headcount that held roughly flat at ~312. Mobile Power (pay-per-use battery hire) and BD Auto and Energy are the same shape smaller. This tier is buying position in markets that don’t pay yet.

Story two: contract-driven surges. Kelvin Hughes’ +68% at a 0.3% margin is a radar maker inside a German defence group shipping more at roughly breakeven — order-book timing, not a business inflection. In-Space Missions (+52%, loss-making) is a satellite builder scaling inside a defence prime.

Story three — the signal: profitable growth backed by hiring. CRFS (+41% turnover, +11% staff, 51% margin) and Veripos (+43%, 29% margin, offshore positioning systems) are the genuine article, and further up the size scale Anord Mardix (+17%, +12% staff) is the same signal at ten times the revenue. Note what those three sell into: defence spectrum monitoring, offshore energy, and data centres.

Market structure: a genuinely fragmented industry

Concentration here is low by the standards of the markets we map — the top 5 hold just 24% of visible turnover and it takes 100 companies to reach 90%. That flatness is the structural point: beneath a thin layer of multinational UK arms sits a broad, old, specialist mid-market where dozens of £20–100M firms each own a defensible niche. For a buyer — trade or private equity — this is what a target-rich environment looks like, and the 9% of the map already carrying Holdings/Bidco-style names suggests the buyers know it.

An old industry with almost no new entrants

Nearly 40% of the map — 74 of 191 companies — predates 1990, and only 16 companies were incorporated in the last decade. The high-margin specialists are overwhelmingly old: Megger’s company dates from 1923, Dewhurst’s from 1919, Lucy Electric’s line goes back to a Victorian Oxford ironworks. Decades of accumulated product trust is the moat in safety- and grid-critical kit — nobody buys a fire panel or an 11kV switch from a startup. The few young companies on the map are the venture tier (ITM’s trading entity, In-Space, Mobile Power), which is exactly where you’d expect the new-technology risk to sit. Ownership splits 102 corporate / 85 individual, with about 9% carrying the Holdings/Bidco/Topco naming that fingerprints a buyout or a planned exit.

What the map shows

1. Turnover and profit live in different places. The multinationals’ UK arms book the biggest revenue lines at 1–3% transfer-priced margins; UK-based specialist manufacturers one tier down earn 20–50% — though several of the best (Deep Sea, CRFS, Froment) are themselves foreign-owned.
2. The clever box beats the big box. Deep Sea Electronics (43.7%), N.J. Froment (35.9%), Megger (31.6%) and CRFS (51.2%) make controllers, test kit and sensors — IP-dense products where the margin is in the engineering, not the metal.
3. Electrification demand is visible and hiring-backed. Anord Mardix (data-centre switchgear) grew 17% with staff up 12%; Eaton’s UK switchgear arm grew 21%; grid-monitoring and grid-switchgear specialists anchor the best-run table.
4. The hydrogen tier is the map’s cash furnace. ITM Power lost £45.4M on £26M of revenue — 1.7× its turnover, and that includes a one-off £13.1M Linde settlement — the energy-transition ventures are buying position, not earning yet.
5. Fire detection is a quiet British profit machine — Apollo and Advanced (both Halma-owned) and Hochiki UK together clear £60M+ of profit — and it shows why the best UK specialists keep getting acquired.
6. It’s one of the flattest markets we’ve mapped — top 5 = 24% — an old, fragmented specialist mid-market with almost no new entrants, which is exactly the profile consolidators hunt.

Methodology and caveats

This covers the 191 UK electrical-equipment companies that publish a full profit-and-loss; smaller workshops file abridged accounts with no figures and don’t appear, and several electrical-adjacent giants report through companies mapped elsewhere — see our electrical contractors, electricity generation and data-centres reports. Group structures matter throughout: the UK arms of global groups report margins set by intragroup pricing (thin at Bosch, Domino and Eaton; unusually fat at KLA), so their profit lines are not comparable with independents’, and a few groups appear through more than one entity (ITM Power’s listed group and trading subsidiary; the two Camlin companies), which we count once in the narrative. Business descriptions are directional. Figures are approximate — verify against a company’s own accounts before relying on any single number. This is analysis, not financial advice.