UK car-parts manufacturing: the profit is in petrol, the losses are in electric

About 119 UK car-parts manufacturers publish a full profit-and-loss, booking £7.19bn of combined turnover — and between them they keep about a penny in the pound. The profitable companies earned roughly £393M; the loss-makers burned £314M; the whole industry netted just £79M. Where the profit sits tells you exactly where British parts-making stands in the electric transition. The most profitable company on the map, by a distance, is Phinia Delphi UK — £100.2M of pre-tax profit, a quarter of everything earned across all 119 companies — and it makes fuel-injection systems, the technology electrification retires. The biggest loss is Fortescue Zero — £159.7M in its newest accounts, to June 2025 — half of all the losses on the map, more than double the £72.6M it burned the year before, on just £80.7M of turnover: the price the Oxfordshire battery-technology house formerly known as Williams Advanced Engineering is paying to chase batteries. And the plants in between, the ones that feed Jaguar Land Rover and Nissan, mostly earn next to nothing in either direction. Figures are approximate — verify against a company’s own accounts before relying on any single number.

Rule one: most of these companies don’t set their own prices

Before reading any margin below, ask who the customer is. This map holds three different kinds of business:

• Captive plants of global groups, supplying one or two carmakers just-in-time. ZF Chassis Modules (Solihull) is the purest specimen: £166.9M of turnover with 73 employees, assembling sequenced axle modules a few miles from the JLR lines, at a margin of roughly zero. Adient Seating UK delivers £235.8M of seats for a pre-tax result of −£21k — a rounding error on a quarter of a billion. These entities’ “margins” are negotiated inside supply agreements and group transfer pricing, not won in a market.
• Group accounting vehicles. Wanfeng MLTH Holdings reports £23.9M of turnover, £23.9M of profit and no employees — that is dividend income wearing a manufacturer’s label. The Tenneco group splits its UK friction-and-sealing business across several companies, with the profit landing where the group puts it (see below). Profit sits on this map where a group chooses to book it, not always where the work is done.
• Genuine independents and aftermarket makers — remanufacturers, catalytic-converter and turbo-parts specialists, vehicle converters. This is the only tier where a margin measures the business, and it is where most of the reliable profit lives.

Two neighbours are worth naming for what they are not. The warehouses, factor chains and tyre importers that sell parts are a different and much bigger trade — £13bn of it, mapped in our motor parts report. And the carmakers’ own engine and pressing plants don’t appear here at all; they report inside the vehicle-makers.

The giants: cost-plus country

*Artifex’s figures are as filed for a 15-month period (January 2024 to March 2025) after a year-end change — roughly £321M annualised, which would still rank it third — so no growth is shown against its 12-month 2023 year (£248.4M of turnover, £8.7M of profit). †Schrader reports in US dollars ($300.1M of turnover, $31.3M of profit), converted here at the period-average rate. ‡SAI’s and Hiab’s rows carry their December-2025 accounts, which reached the register in the days before publication; headcounts from those newer accounts are not yet in our data. Year-ends differ across the table — most run to December 2024 — so adjacent rows can be up to a year apart.

Seven of the twelve biggest either lose money or keep less than a penny in the pound. Strip Phinia out and the other eleven earned £55M on £2.8bn of sales — 2.0%. That is the economics of being a tier-1 supplier in Britain: the giants of this map are mostly local limbs of global groups (ZF, Adient, Marelli, Forvia, Grupo Antolin, Opmobility), planted next to the carmakers they serve and paid roughly what it costs to run them. The West Midlands rows read as one JLR supply corridor — Artifex and ZF in Solihull, SAI at Fradley, Antolin in Redditch — and the hardest contraction is there and in the Nissan orbit in the North East. SAI’s newest accounts took away what looked like the corridor’s one bright spot — sales down 17% to £141.4M and a swing from £7.9M of profit to a £1.7M loss — while in the Nissan orbit Highly Marelli (climate systems, Washington) lost £13.4M on turnover down 9% and Snop UK (pressings, Sunderland) lost £4.6M on turnover down 24%.

The exceptions prove the rule. Phinia Delphi’s 17% margin is combustion legacy — fuel-injection systems sold worldwide, with group technology income behind it, on a product line the electric transition is scheduled to retire. Schrader and BorgWarner earn real double-digit margins on proprietary product (tyre-pressure sensors; engine and emissions kit) rather than sequenced assembly. Marelli’s UK loss came in a year its global parent went through a court-supervised restructuring. And Multimatic’s +24% is the niche-vehicle business booming — at a 0.5% margin.

One more name near the top of the raw ranking isn’t a factory at all in the UK sense: CT Automotive Group is a London-listed (AIM) interior-trim designer that reports in dollars — $119.7M of revenue and $7.5M of pre-tax profit in its 2024 year, roughly £94M and £6M at that year’s average rate — and its ~1,900 employees mostly work in its plants overseas. Read it as a global business with a British flag, not British manufacturing output.

The shape of the market

The entry ticket to parts-making is a plant, and it shows: the £1–5M band — where most industries keep a crowd of small firms — holds just four companies. Below £1M sit legacy shells and run-off entities, not businesses. The real market starts at £5M and runs to about £600M, with profitability decent by headcount (63–73% of companies in each band make money) but thin by margin — the median company keeps about 3.5p of every pound.

Where the money is: the aftermarket and the niches

The mid-market companies that earn a genuine margin mostly share one trait: their customer is not a carmaker’s purchasing department. They convert vehicles, remanufacture parts, or own a specialist product sold into the aftermarket and commercial-vehicle world.

…and four more profitable £25–45M operators behind them. *Knorr-Bremse’s 47 staff on £51M of sales says supply-and-support economics, not a factory; Truck-Lite’s 28.5% is far above anything a lighting plant normally earns — treat both margins as group arithmetic until the accounts say otherwise.

Two names the raw ranking would include are left out. Federal-Mogul posts a 35% margin on £55.3M — but its Tenneco sister companies F-M Motorparts and Federal-Mogul Controlled Power lost £9.6M and £13.6M in the same year; where the UK profit lands in that group is a corporate decision, not a market verdict. And ADV Brightware Manufacturing’s 32% margin on shrinking sales is too rich for trim-making — something else is in that profit line.

The standout is the top row. GM Coachwork converts vehicles for wheelchair users from a Devon village — £98.3M of turnover, up 27%, staff up 18%, at a 9.1% margin, riding the boom in mobility-scheme demand. The best business in British parts-making isn’t supplying a car plant; it’s modifying the cars afterwards.

Growth, read with care — in a market where 60% shrank

The growth table below is the exception, not the trend: of the 99 companies above £2M with a comparable prior year, 59 shrank, and a third lost 10% or more of their revenue. Companies representing 56% of the sector’s comparable turnover went backwards. The contraction is concentrated exactly where you’d expect — the OEM-facing plants: Futaba (Burnley, −30%), Aisin (Birmingham, −32%), Magna Exteriors (Liverpool) (−71%), MSSL (GB) (Gateshead, −84%) — model changeovers and lost platforms hitting one plant at a time.

The genuine, hiring-backed profitable growers are GM Coachwork (+27%, staff +18%), Grayson (+27%, +11%), Sideline Design (+21%, +10%) and Welsh trim-maker Matikon (+52%, +14%). Motion Applied’s +62% — the Woking advanced-engineering house that grew out of the McLaren group’s technology arm — came with headcount down 6%: contract wins, not capacity building. Richmond Design & Marketing is buying growth at a 29% loss.

And then there’s the fastest-hiring “car-parts maker” in Britain, which makes Formula 1 engines. Three companies on one Milton Keynes campus — Red Bull Powertrains (£136.9M), Red Bull Powertrains 2026 (£139.8M, staff up 55% to 565) and Red Bull Advanced Technologies (£10.5M) — book £287M between them, billed within the racing group as the team brings its new-era engine in-house. It is cost-plus economics like the tier-1 plants, with one difference: this customer is hiring.

Market structure: the flattest top of any map we’ve drawn

No one consolidates this industry. The top five companies hold just 28.8% of visible turnover — against ~66% in pubs and ~38% in road freight — because the “market” is really dozens of separate plants, each tied to its own customer and platform, with no reason to merge at the UK level. What concentration exists is corporate, not competitive: the Red Bull trio, the three Autocraft companies in Grantham, the Auria and Tenneco clusters and the two SAI entities are single organisations reporting through multiple names.

Old factories, few founders

This is one of the oldest cohorts we’ve mapped: 45 of the 119 companies predate 1990, and another 28 date from the 1990s — the era Japanese transplants and their suppliers arrived. Then it stops. Just four companies were founded between 2010 and 2015. The 2016–20 cohort of 16 is mostly restructuring vehicles and renamed group entities rather than new factories, and the four 2021+ arrivals are dominated by the Red Bull engine companies. Ownership says the same thing: 71 of 119 are corporate-owned, most of them by overseas groups, and only about 8% carry a Holdings/Bidco-style name — private equity has little appetite for cost-plus plants either.

What the map shows

1. The whole industry keeps about a penny in the pound. Roughly £393M earned by the profitable, £314M burned by the rest — £79M net on £7.19bn of turnover, with a median margin near 3.5%.
2. The profit is combustion legacy; the losses are electric. Phinia’s fuel-injection business earned £100.2M — a quarter of all profit on the map — on technology the EV transition retires, while the battery-technology bet Fortescue Zero produced the map’s biggest loss: £159.7M in its newest accounts, more than double the £72.6M it burned the year before, and half of all the losses on the map.
3. Tier-1 Britain is cost-plus country. Seven of the twelve biggest companies lose money or keep under a penny per pound; without Phinia, the top of the table earns 2.0%. ZF’s 73-person, £167M Solihull module plant is the model in miniature.
4. The sector is shrinking. 60% of comparable companies had falling revenue — 56% of the sector’s turnover went backwards — with the JLR corridor and the Nissan orbit contracting hardest.
5. The reliable money avoids the carmakers’ purchasing departments — remanufacturing, catalytic converters, turbo parts, truck kit and above all vehicle conversion: GM Coachwork’s £9M on wheelchair-accessible vehicles is the best genuine business on the map.
6. Nobody is building new parts-makers. Four companies founded in 2010–15; the newest significant arrivals make Formula 1 engines, not car parts.

Methodology and caveats

This covers only the 119 UK parts-and-accessories manufacturers that publish a full profit-and-loss; smaller makers publish abridged accounts with no figures, the carmakers’ own component plants report inside the vehicle groups, and some large component businesses report through companies classified elsewhere — the parts distribution trade appears in our motor parts map. Group structures report at several levels: the Red Bull, Autocraft, Auria, Tenneco and SAI clusters each place multiple related companies on this map, so combined-turnover figures overstate the distinct-group total, and captive plants’ margins reflect intra-group pricing rather than market performance — never compare them with an independent’s. Year-ends differ by up to a year across the tables; companies without a comparable prior period show no growth figures; zero-employee holding vehicles and extreme proportional outliers are excluded from the charts. The map was drawn from each company’s latest accounts in our dataset in early July 2026; a wave of December-2025 and June-2025 year-ends reached the register in the days before publication, and where a newer filing materially changes the picture — Fortescue Zero, SAI Automotive Fradley, Hiab — the text and the giants table carry the newer figures, while the charts and the distribution, concentration and cohort tables reflect the earlier cut. Accounts presented in foreign currencies (Schrader Electronics, CT Automotive) are converted at the period-average exchange rate for the filing year. Artifex Interior Systems’ latest accounts cover a 15-month period to March 2025 after a year-end change; its as-filed figures sit in the tables and totals, with the annualised equivalent footnoted. Figures are approximate and business descriptions are directional — verify any specific figure against the company’s own accounts. This is analysis, not financial advice.