Aerospace Defence Companies in Leicester: 42 Active Firms (2026)
Aerospace and defence companies design, manufacture, maintain or supply aircraft, systems and controlled components around Leicester.
Procurement usually sits with engineering, quality and programme teams rather than a single buyer, with commercial approval tied to certification, traceability and export status. Around Leicester, the main buying centres tend to be precision manufacturing, maintenance and repair, systems integration, and specialist component distribution. Customers are usually prime contractors, tiered suppliers, maintenance operators, public-sector defence buyers and export-led industrial groups. Engagements are often qualification-led, with small-batch production, repair schedules or controlled component supply agreed through framework, project or programme contracts rather than short transactional purchasing.
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In and around Leicester, 42 aerospace and defence companies are actively trading, making this a compact supplier base rather than a broad national cluster. Reported employment totals 1,162 people, so the local footprint is large enough to include production, inspection and programme-management capacity, but still reads as specialist supply-chain activity rather than prime-contractor scale. The cohort is likely to matter most where Midlands engineering skills, controlled-component handling and proximity to UK manufacturing customers intersect.
Civil aviation work sits under the UK Civil Aviation Authority for safety oversight and certification. ADS notes that the CAA has gained greater rulemaking and certification authority, while alignment with EASA and closer FAA cooperation remain relevant for market access. Defence and dual-use exports sit under UK strategic export controls: exporters must check whether items, end use or sanctions require licensing through the Export Control Joint Unit. Exporting controlled items without the correct licence is a criminal offence, making compliance capability part of the commercial proposition rather than an administrative afterthought.
Growth appears more likely to come from qualification wins, export permissions and maintenance demand than from broad new-company formation. Suppliers with documented quality processes, controlled-component traceability and export-control discipline tend to have a clearer route into defence and civil aviation programmes, but sales cycles can be slow and buyer concentration limits room for speculative expansion. Consolidation pressure may build where owner-managed engineering businesses need succession options, while younger specialists are likely to focus on narrower subsystems, inspection services or regulated distribution niches.
What’s in the file
One row per company, 50+ columns — everything below plus each company’s verified directors, from Companies House filings.
Company data
Verified directors — included
Active director count is the full Companies House board, so it can be higher than the number of names listed — we leave out nominee and formation-agent directors, who aren’t worth contacting. It’s blank for the small number of companies whose officers we haven’t fetched yet.
You’re charged per business, not per row. Where a business trades through several registered companies you get every one, and the Group Primary column marks one row per business — filter to those and the count matches your invoice. Rows sharing a website are not automatically one business: franchises and multi-site operators each count separately, and where names don’t prove a relationship we count them apart rather than guess.
42
Active firms
2026
4
Companies over £5M
Reported revenue
9
Incorporated since 2022
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Key facts
About 9% of the trading cohort reports turnover above £5M (4 of 42 firms) — the rest sits below that revenue band.
21% of the cohort was incorporated since 2022 (9 firms), so a sizeable share is in its first few filing cycles.
The UK Civil Aviation Authority oversees civil aviation safety and certification, and its greater rulemaking role makes regulator alignment a market-access issue for aerospace suppliers.
Exporters of controlled defence or dual-use items must check the consolidated list and apply to the Export Control Joint Unit where licences are required; exporting controlled items without the correct licence is a criminal offence.
ADS’ 2024 aerospace outlook puts UK aerospace employment at 104,000 people.
GOV.UK reports UK defence export orders of £13.2 billion in 2024, up from £11.9 billion in 2023.
Aerospace products accounted for 53% of UK defence export orders over 2020–2024, the largest product category across the period.
Top Leicester Aerospace Defence companies
Provides maintenance, repair and overhaul (MRO) services for aircraft avionics systems. Sells and modifies cockpit displays, navigation and communication equipment, instruments and recorders, and…
Serves B2B aviation customers, including fixed- and rotary-wing aircraft operators worldwide and Airbus, Boeing, Embraer and Dornier fleet operators needing OEM-approved avionics support.
Location
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Manufactures high‑precision machined components for aerospace and power generation industries, specialising in gas turbine ring components and complex structures. Provides turning, milling, mill‑turn…
Serves B2B customers in the aerospace and power generation sectors, including advanced engineering companies and supply chains needing high-precision fabricated and machined components.
Financial Health
N/AN/A · 1% CAGR over 1y
Location
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Computed from 2 filingsFinancial Health
StableStable
Location
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Develops nuclear power technologies for space and terrestrial applications, including radioisotope power systems, microreactors, and advanced nuclear fuels. Focuses on providing energy solutions for…
Serves space and non-space organisations requiring power solutions for extreme environments, including customers in space science, exploration, and Earth-Moon ecosystem infrastructure.
Financial Health
N/AN/A
Location
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Computed from 4 filingsDevelops and supplies composite material solutions and product development services, including tooling boards, pastes and high‑performance structural composites. Supports design, material…
Serves B2B manufacturers and product development teams in wind energy, Formula 1, marine, automotive, aerospace, rail/mass transport and infrastructure, especially those building high-performance…
Financial Health
WeakWeak · Hiring · 36% CAGR over 3y
Location
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Computed from 5 filingsProvides CNC machining and subcontract manufacturing services including CNC turning, 3–5 axis milling, wire and spark EDM, centreless grinding, and laser marking to produce precision components,…
Serves B2B customers in aerospace, petrochemical, motorsport, medical, marine and rail sectors, including firms needing machined components, fasteners, fittings, prototypes and short-turnaround…
Financial Health
StableStable · -2% CAGR over 4y
Location
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Computed from 3 filingsDesigns and manufactures metal forming machinery including CNC spinning, flow forming, and truck disc forming systems. Develops associated control software and provides custom machine engineering,…
Serves B2B manufacturers in aerospace, military and defense, robotics and automation, and automotive sectors, targeting production and engineering teams with specialised metal forming requirements.
Financial Health
HealthyHealthy · Hiring · 22% CAGR over 2y
Location
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Computed from 5 filingsProvides precision engineering and CNC machining services, including CNC milling and turning, wire EDM, grinding, and heat and surface treatments. Manufactures precision components and tensile…
Sells to B2B customers needing precision-machined components, including manufacturers and engineering buyers in aerospace, medical, marine, pharmaceutical, vehicle, transport, machinery, defence and…
Financial Health
StrongStrong
Location
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- Sigma10145833
Manufactures precision‑engineered aerospace components for civil and military aircraft, including tube and pipe assemblies, ducts, manifolds, sheet and machined parts, and specialist fasteners, and…
Serves aerospace B2B customers, including airframe OEMs, Tier 1 suppliers and engine OEMs involved in civil and military aircraft platforms.
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Computed from 5 filingsDesigns and manufactures fast hole EDM drilling machines for precision drilling of cooling holes in aerospace and industrial gas turbine components. Also develops laser drilling, laser ablation, ECM…
Serves aerospace and industrial gas turbine OEMs, tier-one suppliers, and component repair/manufacturing firms producing or refurbishing turbine blades, vanes and segments.
Financial Health
StrongStrong · Growing, Hiring · 14% CAGR over 4y
Location
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Computed from 3 filingsDevelops and supplies tactical unmanned aerial systems for military and defence applications. Integrates UAV platforms with surveillance sensors and payloads to provide ISTAR capabilities for land…
Serves military and defence-sector customers, including armed forces and public-sector defence procurement teams in international markets, with emphasis on land and maritime mission requirements.
Financial Health
DistressedDistressed · -88% CAGR over 2y
Location
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Computed from 3 filingsDesigns and manufactures precision ballscrews for aerospace, defence and industrial applications, including miniature and high‑temperature components for actuators. Provides ballscrew repair,…
Serves B2B OEMs, primes and engineering teams in aerospace, defence, space, automotive, food and beverage, and machine tool sectors, including customers needing specialist ballscrew manufacture,…
Financial Health
StrongStrong · Hiring · 32% CAGR over 2y
Location
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Computed from 5 filingsProvides electroplating services specialising in hard chromium and silver deposition. Plates components including aluminium and Inconel parts for aerospace and defence engineering, supplying surface…
Serves aerospace and defence manufacturers, repair providers and UK Ministry of Defence contractors, including aircraft, aero-engine, braking systems, hydraulics and nuclear submarine supply chains.
Financial Health
StrongStrong · Hiring · 6% CAGR over 4y
Location
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Computed from 2 filingsDesigns and manufactures precision elastomer sealing products, including aerodynamic seals, bellows, ducting seals, fire seals and moulded components. Supplies engineered sealing solutions used in…
Serves B2B aerospace and aviation manufacturers, particularly airframe and aircraft engine manufacturers operating in demanding environments.
Financial Health
HealthyHealthy · Growing, Hiring · 15% CAGR over 1y
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Provides precision metal finishing services for aerospace and industrial components, including polishing, deburring, blasting, barrelling, vibro and super polishing, titanium component finishing, and…
Serves global B2B customers in aerospace, nuclear and power generation, particularly manufacturers and suppliers needing finishing of precision metal components and high-volume parts.
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Computed from 5 filingsDistributes tangless wire threaded inserts and installation tooling from Kato Precision, and supplies specialist fasteners and fittings made from materials such as titanium and Inconel, with…
Serves B2B engineering, procurement and manufacturing customers in aerospace, motorsport, petrochemical and telecoms industries, particularly those sourcing specialist fasteners, fittings and tooling…
Financial Health
WeakWeak · Hiring · 6% CAGR over 4y
Location
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Computed from 5 filingsManufactures precision‑engineered components for the aerospace and marine industries. Provides CNC machining and engineering production of high‑tolerance parts, operating to AS9100 and ISO 9001…
Serves B2B aerospace and marine customers, including prime contractors and engineering manufacturers requiring precision components and certified supplier standards.
Financial Health
WeakWeak · -6% CAGR over 4y
Location
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Computed from 3 filingsProvides metal surface treatment and finishing services for engineering and aerospace components, including anodising, electroplating, conversion coatings, painting, bonding and assembly,…
Serves B2B customers in aerospace, defence and general engineering, particularly first-tier engineering companies and engineering primes requiring approved metal finishing supply partners.
Financial Health
DistressedDistressed · -90% CAGR over 2y
Location
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Computed from 5 filingsManufactures technical narrow fabrics including webbings, tapes and elastics. Provides dyeing, finishing, testing and product development services, and produces 3D woven composite fibre…
Serves global B2B clients in defence, aerospace, aviation, fire safety, fall arrest, healthcare, sports and leisure, and industrial sectors needing technical textile and composite components.
Financial Health
WeakWeak · -60% CAGR over 5y
Location
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Manufactures piezoresistive pressure sensors, transducers, and pressure test and calibration instruments, including portable calibrators, pressure controllers, and air data test sets. Products are…
Serves B2B engineering, maintenance and calibration teams in aerospace/aviation, energy, electronics/semiconductor, environmental/meteorology, healthcare, industrial, metrology and transportation…
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- JJ Churchill12747384
Financial sub-scores
Computed from 3 filingsProvides precision engineering and manufacturing of gas‑turbine blades and complex components. Offers new product development, volume production and spare parts manufacturing for aerospace, power…
Serves B2B customers in aerospace, power generation and med-tech, including OEMs and Tier 1 supply chains requiring precision-engineered components, new product development, volume manufacture and…
Financial Health
WeakWeak · Hiring · 10% CAGR over 2y
Location
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Computed from 5 filingsProvides non-destructive testing services including magnetic particle, penetrant and visual inspection for engineering and aerospace components. Also manufactures and supplies NDT equipment and…
Serves B2B manufacturing and engineering organisations, from small firms to international groups, with emphasis on aerospace, power generation, motorsport and companies operating or setting up NDT…
Financial Health
WeakWeak · -6% CAGR over 4y
Location
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Computed from 2 filingsFinancial Health
HealthyHealthy · 0% CAGR over 1y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed · 0% CAGR over 4y
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Manufactures and supplies welding wire, brazing alloys, soldering fluxes, and related consumables. Also provides metal powders and wire for additive manufacturing, along with speciality and precious…
Serves global B2B customers in high-tech, quality-critical sectors, including aerospace, aviation MRO, power generation, thermal management, automotive, medical, scientific and emerging technology…
Financial Health
N/AN/A
Location
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Computed from 4 filingsFinancial Health
HealthyHealthy · 0% CAGR over 3y
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Computed from 5 filingsFinancial Health
StrongStrong · Growing · 0% CAGR over 4y
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Computed from 5 filingsProvides avionics support for helicopter and fixed‑wing aircraft, including scheduled maintenance, repair, installation and fault diagnosis of avionics and autopilot systems, delivered through mobile…
Sells to UK helicopter and fixed-wing aircraft owners and operators needing avionics support, including maintenance, repairs and installations. Serves aviation customers with fleets or individual…
Financial Health
WeakWeak · -65% CAGR over 4y
Location
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Computed from 3 filingsDesigns and develops robotic control systems, unmanned ground vehicles and remote operation technology. Provides engineering consultancy and R&D, and supplies control platforms such as the Marionette…
Sells primarily to B2B and public sector buyers in defence, nuclear, agriculture and health, including government defence agencies, laboratories, prime contractors, nuclear agencies, universities,…
Financial Health
StableStable · Hiring · 26% CAGR over 2y
Location
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Computed from 3 filingsProvides contract electronics design and manufacturing services, including product development, prototyping, PCB surface‑mount assembly, cable assembly, testing and turnkey production, supporting…
Serves B2B electronics customers, including established brands and start-ups in medical and life sciences, aerospace and defence, oil and gas, scientific instrumentation, industrial controls,…
Financial Health
StableStable · -1% CAGR over 2y
Location
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Computed from 4 filingsProvides maintenance and repair services for light aircraft, including Rotax engine servicing, gearbox and carburettor work, aircraft inspections, weighing and permit-to-fly renewals. Also…
Serves private pilots, light aircraft and microlight owners/operators, and aviation businesses using Rotax-powered aircraft, plus buyers of light sport aircraft parts through its online shop.
Financial Health
StableStable · 0% CAGR over 3y
Location
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Computed from 5 filingsFinancial Health
DistressedDistressed · 0% CAGR over 4y
Location
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Financial Health
N/AN/A
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Computed from 5 filingsProvides manufacture and supply of knitted and woven fire‑barrier fabrics and interlayer scrims. Offers commission knitting, material sourcing and product development of technical fabrics for…
Serves B2B manufacturers and product developers in aviation, automotive, rail, protective equipment, fire protection and health markets with requirements for technical fire barrier fabrics and…
Financial Health
HealthyHealthy · Hiring · 9% CAGR over 4y
Location
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Computed from 5 filingsFinancial Health
StrongStrong
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Computed from 5 filingsDesigns and manufactures precision machining systems and provides component manufacturing services. Technologies include laser drilling, cutting and welding, micro‑machining, and electrical discharge…
Serves B2B manufacturing organisations in aerospace, energy, medical devices and semiconductor/electronics, including teams producing turbine components, fuel cells, implants, catheters and precision…
Financial Health
StableStable · -70% CAGR over 4y
Location
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Computed from 5 filingsManufactures patterns, moulds, tooling and composite components for prototype and production use. Provides CAD design, 3D scanning, 5‑axis CNC machining, carbon fibre fabrication, resin casting and…
Serves B2B clients in motorsport, automotive and aerospace, alongside artists, sculptors, theatre/dance companies and luxury bespoke furniture/design commissioners.
Financial Health
HealthyHealthy · Growing · 1% CAGR over 4y
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Computed from 4 filingsManufactures precision engineered and engraved tooling, including heading punches, engraved metal and silicone rubber dies, type and wordblocks, branding irons, and nameplates. Supplies components…
Serves B2B manufacturers and printers worldwide, including aerospace fastener producers, food and pharmaceutical packaging firms, cosmetics packaging decorators, security printers, and hot foil…
Financial Health
StableStable · -2% CAGR over 3y
Location
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Computed from 5 filingsDesigns and manufactures bespoke electrical control panels and control systems for marine, aerospace, oil and gas, and industrial equipment. Provides panel building, electromechanical assembly,…
Serves B2B customers in marine, oil and gas, aerospace, engineering, machine tools and material handling, including manufacturers and engineering firms needing custom control system builds.
Financial Health
StrongStrong · Hiring · 22% CAGR over 3y
Location
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- Preci-Spark00661746
Provides precision engineering and manufacturing services including laser machining, electro discharge machining, conventional machining, vacuum brazing and welding. Produces components such as…
Serves B2B engineering and manufacturing customers across multiple industrial sectors, including semiconductor buyers and OEMs needing precision metal components, complex fabrications and assemblies.
Financial Health
N/AN/A
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Computed from 3 filingsProvides precision engineering and CNC machining services, manufacturing machined metal components and parts for industries including oil and gas, aerospace, security, military, and commercial…
Serves business customers in oil and gas, aerospace, security, military and wider commercial sectors seeking precision-engineered components.
Financial Health
StableStable · 0% CAGR over 2y
Location
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Computed from 5 filingsFinancial Health
StrongStrong · Hiring · 19% CAGR over 4y
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How Leicester Aerospace Defence companies work and how to sell to them
What they do
Revenue usually comes from qualified production work, repair and overhaul labour, controlled component supply, and engineering services around test, inspection or integration. Many Leicester-area suppliers mix physical output with documentation-heavy service revenue: tooling charges, non-recurring engineering fees, unit pricing for batches, time-and-materials repair, margin on stocked parts, or call-off work under a framework. Subscription income is less common, although support, maintenance and availability contracts can create recurring revenue. Pricing tends to reflect certification burden, material traceability, low-volume set-up time and the cost of staying on an approved supplier list, not just the part or labour hour.
Who they sell to
Most customers are business or government-side buyers rather than consumers: prime contractors, tiered manufacturers, maintenance operators, defence procurement teams, security programmes and export-facing industrial groups. The buying committee typically includes engineering, quality, programme management, procurement and finance, with export-control or commercial specialists involved where controlled items are in scope. Smaller orders may start as a technical request for quotation, but material programmes usually pass through approved-supplier checks, audits, drawings, sample inspection and contract review. Sales cycles therefore tend to be measured in months, especially where a new supplier must prove traceability, capacity and conformity before commercial terms are signed.
What they buy
Spend tends to follow the audit trail. Aerospace and defence suppliers usually need quality-management systems, document control, contract review, inventory and lot-traceability tools, calibration management, inspection equipment, secure file exchange, cyber security, export-control screening and finance systems that can handle project work, deposits and staged invoices. Manufacturers may also buy shop-floor scheduling, materials planning, tooling, metrology, logistics and specialist insurance. Service providers can pitch recruitment for machinists, quality engineers and programme managers, as well as legal, accounting and grant advisory support. The useful angle is usually risk, proof and margin control, rather than generic productivity claims.
Why and how to sell to them
Commercial intent often appears when a supplier wins a new programme, prepares for an audit, adds controlled stock, takes on export work, changes ownership, hires quality or programme staff, or outgrows spreadsheet-led traceability. Leicester-area aerospace and defence buyers tend to listen when outreach maps to an immediate compliance or delivery risk: failed paperwork, late inspection packs, licence uncertainty, supplier onboarding delays, scrap, rework or cash tied up in small-batch production. Sellers should expect technical validation before budget discussion, and should lead with evidence, implementation effort, integration with existing workflows and a credible route through procurement.
How this list is built
Data sources
This list is built from UK Companies House filings, XBRL accounts data, and semantic analysis of each company's public website. Revenue and headcount figures come from the most recent filed accounts; where the company has not filed, values are estimated using a model trained on filed history and peer benchmarks and are labelled as estimates.
Classification
Rather than relying solely on SIC codes, Firmbase classifies each company semantically: the company's website is crawled, an AI model reads what the company actually sells, and the company is placed into the relevant industry and subsectors. SIC codes are used as one signal but not the only one. This means a company that registered under a generic SIC code but pivoted into (for example) fintech is correctly identified as fintech, not as its original SIC category.
Freshness
The underlying company data is refreshed from Companies House continuously; filings appear in the list within days of submission. The curated list ordering is regenerated when the underlying data moves meaningfully (company count changes by more than 5%, a new company enters the top-ranked segment, or the filed-revenue numbers for the top firms change). You can see the last-updated timestamp near the top of the page.
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Frequently asked questions
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