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Semiconductor Companies in London: 100+ Active Firms (2026)
Semiconductor companies in London design microchips, components and related intellectual property for electronics, communications and industrial systems.
Buying centres tend to sit with engineering, product and operations teams rather than general IT, with commercial sign-off often coming from programme, procurement or finance leads inside hardware-led buyers. London suppliers in this niche usually serve business customers in electronics, communications, industrial technology, defence-adjacent, automotive, aerospace, energy and medical-device supply chains. Engagements are usually consultative: chip design support, embedded electronics, photonics, sensors or specialist intellectual property that has to pass through design-in, validation and qualification before volume revenue arrives. The fit is narrower than general hardware distribution, with more weight on R&D, prototyping and UK-based design than high-volume fabrication.
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London has 110 actively trading semiconductor and microelectronics firms in this cohort, making it a compact market by company count rather than a broad manufacturing base. Reported employment totals 520 people, which points to many design-led and specialist engineering businesses rather than large production sites. The commercial profile is also narrow: only 7 companies sit above £5M turnover, while 24 have been incorporated since 2022. That leaves a visible early-commercial tail, with a smaller group of established suppliers likely to carry most larger customer engagements.
Government treatment of semiconductors is closer to strategic infrastructure than ordinary component supply. Oversight is fragmented across investment screening, export controls and sector-specific customer requirements, rather than handled by a dedicated conduct regulator for the London market. Relevant transactions can fall under the National Security and Investment Act where control of sensitive capability, know-how or intellectual property changes hands. GOV.UK guidance places semiconductor activity within the Advanced Materials area, covering research, development, production and related services. Export-control checks also matter where components, designs or technical assistance could be used in defence-adjacent or dual-use systems.
Scale-up pathways appear uneven. London has the customer proximity and capital-market access that suit design-led semiconductor firms, but specialist hardware sales tend to move at the pace of qualification cycles, export checks and customer procurement. Early-commercial businesses are likely to keep leaning on R&D services, licensing and engineering consultancy while they prove repeatable product demand. Consolidation may come through customer acquisition, design-house roll-ups or overseas buyers seeking UK capability, though the National Security and Investment Act means some transactions will carry more scrutiny than a conventional software deal.
110
Active firms
2026
7
Over £5M turnover
Reported revenue band
24
Incorporated since 2022
Recent company formation
Key facts
About 6% of the trading cohort reports turnover above £5M (7 of 110 firms) — the rest sits below that revenue band.
21% of the cohort was incorporated since 2022 (24 firms), so a sizeable share is in its first few filing cycles.
UK semiconductor policy treats the sector as strategically sensitive, with public support focused on R&D, design and compound semiconductors.
The National Security and Investment Act can require mandatory notification for certain semiconductor acquisitions, including activity involving research, development or production, intellectual property, know-how and related services.
GOV.UK’s 2024 sector study identified 623 in-scope UK semiconductor companies, including 210 dedicated semiconductor companies.
Dedicated UK semiconductor companies generated £9.6 billion in revenues in 2022, about 2% of global semiconductor revenues.
Most semiconductor manufacturing takes place in East Asia, particularly Taiwan, leaving the UK positioned around R&D, design and related services rather than high-volume fabrication.
Top London semiconductor companies
Intrinsic Semiconductor Technologies Limited
Trajectory
5y · 2019–NowDevelops silicon oxide‑based resistive RAM (RRAM) non‑volatile memory technology for semiconductor chips. Enables direct on‑chip memory integration in microcontrollers and edge processors, supporting…
Serves semiconductor companies and chip designers developing embedded systems, next-generation microcontrollers and edge AI processors, especially teams needing integrated non-volatile memory for…
Financial Health
Insufficient historyInsufficient history · 200% CAGR over 2y
Location
Designs high‑performance semiconductor chips, providing System‑on‑Chip (SoC) architecture, IP selection, front‑end and back‑end design, and tapeout support. Develops customised ASICs for applications…
Sells to B2B semiconductor and electronics product companies in AI, automotive, 5G, networking and related advanced-technology markets, particularly engineering teams developing custom SoCs or ASICs.
Location
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDesigns and develops RISC‑V based processor core intellectual property, development boards, and software tools. Supports creation and testing of customizable microprocessor architectures for…
Serves B2B semiconductor and electronics teams designing compute platforms for AI/ML, automotive, edge, IoT/embedded, consumer devices, data centres, space/aerospace and defence, and storage…
Financial Health
StrongStrong · Growing, Hiring · 15% CAGR over 2y
Location
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDesigns and manufactures CMOS image sensors, ASICs and X‑ray detector systems for medical, industrial, scientific and security imaging. Provides wafer‑scale sensors, detector arrays and custom sensor…
Sells to B2B customers needing X-ray detectors and CMOS image sensors, including medical and dental device makers, industrial NDT firms, scientific users, veterinary and security equipment…
Financial Health
StableStable · Hiring · 7% CAGR over 2y
Location
Innosilicon Technology UK Limited
Trajectory
3y · 2022–NowFinancial sub-scores
Computed from 3 filingsProvides semiconductor IP cores and system‑on‑chip design services, including high‑speed interface, memory and SerDes IP, custom ASIC and SoC development, chiplet and packaging design, and…
Serves semiconductor and electronics companies designing AI, HPC, automotive, wireless, edge AI and AIoT chips, including teams building GPU, NPU, CPU, FPGA and custom SoC products.
Financial Health
StrongStrong · Growing, Hiring · 27% CAGR over 2y
Location
MINT NEUROTECHNOLOGIES LIMITED
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDesigns and supplies application‑specific semiconductor integrated circuits for neural implant devices, including chips for neural signal acquisition, stimulation control, signal processing, power…
Serves medical-device companies, system integrators, research institutions, clinical groups and consortia developing active implantable medical devices, brain-computer interfaces and neural interface…
Financial Health
StableStable · -87% CAGR over 2y
Location
Presto Engineering Group Uk Ltd
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsProvides ASIC design and semiconductor engineering services, including custom IC development, IP platforms, package design, testing, qualification, and foundry tape‑out support, helping companies…
Serves B2B technology companies developing products for industrial, automotive, aerospace, medical and communications markets, particularly teams needing custom microelectronics, ASICs and…
Financial Health
HealthyHealthy · -9% CAGR over 2y
Location
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDesigns and supplies analogue and mixed‑signal CMOS integrated circuits for high‑speed optical communications and networking. Products include transimpedance amplifiers, laser drivers, receivers,…
Serves B2B optical communications and networking equipment manufacturers, including FTTx/PON, datacom, wireless infrastructure and telecom suppliers.
Financial Health
StableStable
Location
KOPIN LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures microdisplays, optical modules, and integrated vision systems for wearable headsets and visual display devices. Provides custom and commercial solutions used in defense,…
Sells B2B to OEMs and product teams developing wearable vision systems, headsets and display products for defense and security, training and simulation, enterprise and industrial, medical, and…
Financial Health
DistressedDistressed
Location
SPECTRUM LOGIC LIMITED
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures CMOS X‑ray flat panel detectors for imaging applications. Products are used in medical and veterinary radiography, electronics inspection, non‑destructive testing, and…
Serves B2B customers in medical and veterinary radiography, electronics inspection, non-destructive testing, industrial/scientific X-ray imaging and life science labs using Western blot scanning.
Financial Health
StrongStrong · Hiring · 38% CAGR over 5y
Location
Manufactures thin‑film pressure sensing elements and sensors using electronic strain‑gauge technology. Produces components for pressure and temperature measurement used in automotive, industrial, and…
Sells to B2B manufacturers and OEMs in global automotive, industrial, off-highway and machinery markets that require pressure sensing elements for equipment, including safety-critical applications.
Location
Siloton Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops miniaturised optical components for medical imaging based on photonic chip technology and optical coherence tomography (OCT). Provides OCT chip development kits, customised photonic…
Sells to B2B medical device developers and imaging companies building OCT products, particularly in ophthalmology and disease monitoring. Also serves research consortia seeking customised…
Financial Health
StrongStrong
Location
Crypto Quantique Limited
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDevelops hardware security IP and device management software for IoT and semiconductor devices, including physical unclonable function (PUF) technology, root‑of‑trust components, cryptographic cores,…
Targets B2B silicon teams, SoC and IC designers, chiplet developers, and IoT device manufacturers in sectors including medical devices, Industry 4.0, automotive and radio modules.
Financial Health
WeakWeak · -9% CAGR over 3y
Location
CENTRONIC LIMITED
Trajectory
2y · 2023–NowFinancial sub-scores
Computed from 2 filingsFinancial Health
StableStable · 1% CAGR over 1y
Location
ATLANT 3D LIMITED
Trajectory
2y · 2024–NowDevelops atomic‑scale manufacturing technology for micro‑ and nano‑fabrication. Designs and supplies nanofabrication equipment, including the Nanofabricator platform, using direct atomic layer…
Serves R&D teams, universities and industrial manufacturers across the microelectronics value chain, including semiconductor, photonics, MEMS/sensor, microfluidics, RF and printed electronics…
Financial Health
Insufficient historyInsufficient history
Location
Develops, manufactures and licenses cadmium‑free quantum dot nanomaterials. Tunes optical and electronic properties of nanoparticles for use in display technologies and infrared sensing applications…
Sells to businesses developing electronics and advanced technology products, particularly device makers and OEMs in display, sensing and IoT markets, including mobile, automotive, wearables,…
Location
MARINE AIR TECH LTD
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDesigns, manufactures, assembles and tests high‑power semiconductor assemblies and thermal management products. Supplies heat sinks, thyristor controllers, semiconductor modules and discretes,…
Sells to OEMs, engineers and industrial buyers needing power semiconductor assemblies, thyristor controllers, heat sinks and thermal management components for specialist power electronics…
Financial Health
StableStable
Location
VAIRE COMPUTING LTD
Trajectory
3y · 2022–NowFinancial sub-scores
Computed from 3 filingsDevelops computer chip architectures based on reversible computing that recycle energy from calculations instead of dissipating it as heat. Designs hardware intended to deliver high‑performance,…
Targets B2B customers running AI infrastructure, especially data centre operators and compute providers constrained by power, cooling, throughput and latency requirements.
Financial Health
StrongStrong · Hiring · 123% CAGR over 2y
Location
Develops semiconductor-based DNA sequencing technology and diagnostic platforms for rapid genomic analysis at the point of care. Builds microchip sequencing systems and tests for detecting infectious…
Targets hospitals, clinicians and clinical laboratories, especially teams managing infectious disease, sepsis and antimicrobial resistance, with relevance to healthcare systems and public health…
Location
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDevelops hardware and software security technologies for servers, edge and IoT devices, including Trusted Platform Modules, post‑quantum cryptography accelerators, firmware signing and device…
Sells to governments and businesses building or operating critical servers, AI/HPC data centres, edge IoT devices and embedded hardware, including teams managing secure device supply chains and…
Financial Health
StableStable
Location
RANSemi Limited
Trajectory
2y · 2023–NowFinancial Health
Insufficient historyInsufficient history
Location
RF & MM WAVE DESIGN LTD
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsFinancial Health
StableStable · 0% CAGR over 1y
Location
ESWIN UK LIMITED
Trajectory
5y · 2022–NowFinancial sub-scores
Computed from 5 filingsDevelops RISC‑V–based semiconductor chips, computing platforms and software for intelligent devices. Provides system-level hardware and software solutions, including processors, IP modules and…
Serves B2B electronics, automotive, industrial and robotics customers, including makers of smart home appliances, office devices, smartphones, wearables, tablets, smart manufacturing, energy,…
Financial Health
HealthyHealthy · -2% CAGR over 4y
Location
OMC (GB) Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures optoelectronic components and lighting products, including fibre optic cables and assemblies, LED backlights, optical mouldings, high‑power LEDs, displays, fibre optic…
Sells to B2B customers such as electronics OEMs, design engineers, product developers and lighting specifiers working on industrial, commercial and equipment-display applications.
Financial Health
HealthyHealthy · Hiring · 6% CAGR over 4y
Location
HYPERIO TECHNOLOGY LTD
Trajectory
5y · 2020–NowFinancial sub-scores
Computed from 5 filingsDevelops and supplies LiFi research and development kits, RF and microwave test instruments, and optical communication systems. Provides programmable wireless testing equipment and custom solutions…
Serves B2B and public-sector R&D teams in telecoms, defence, marine research and wireless communications, including engineers developing LiFi, RF, microwave, optical, underwater and mesh network…
Financial Health
WeakWeak · 0% CAGR over 4y
Location
Orca Computing Limited
Trajectory
3y · 2023–NowFinancial sub-scores
Computed from 3 filingsDevelops photonic quantum computing systems and quantum accelerators using fibre‑interconnected architectures. Produces rack‑mounted PT Series machines designed for applications such as generative…
Serves enterprises, research organisations and developer teams pursuing quantum-accelerated generative AI and optimisation, including on-premises data centre and cloud environments across industrial…
Financial Health
StableStable · Hiring · 15% CAGR over 2y
Location
CAMBRIDGE GENEFIT TECHNOLOGIES LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops touch interface technology and display modules using piezoelectric and force‑sensitive sensing. Supplies UltraTouch human‑machine interface solutions for industrial, automotive, medical,…
Serves B2B OEMs, product designers and systems integrators in manufacturing, AV, medical, automotive, agriculture, oil and gas, defence, industrial equipment and consumer electronics markets.
Financial Health
StableStable
Location
OKSA AUTOMATION LIMITED
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsFinancial Health
WeakWeak · 0% CAGR over 3y
Location
BROMLEYSAT LTD
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsFinancial Health
DistressedDistressed
Location
TERADYNE LIMITED
Trajectory
2y · 2023–NowFinancial sub-scores
Computed from 2 filingsDesigns and manufactures automated test equipment for semiconductors and electronic devices, including memory, mixed‑signal and wireless test systems. Also develops industrial robotics such as…
Sells B2B to semiconductor and electronics manufacturers, production test teams, wireless, memory and storage suppliers, defence and aerospace organisations, and industrial companies using…
Financial Health
StableStable · 0% CAGR over 1y
Location
LEM Solutions Limited
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures electrical measurement components including current and voltage sensors, Rogowski coils and energy meters. Supplies sensing solutions used in automotive systems, EV chargers,…
Serves B2B engineering and procurement teams at OEMs and system integrators in automotive electrification, EV charging, smart grid, renewable energy, industrial automation, welding, traction and…
Financial Health
DistressedDistressed
Location
COHERENT TECHNOLOGIES LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures lasers, photonic components, optical networking equipment and engineered materials used in industrial manufacturing, datacentre and telecommunications networks, electronics…
Serves B2B customers in industrial, communications, electronics and instrumentation markets, including hyperscale datacenters, AI network operators and technology manufacturers.
Financial Health
StableStable · Hiring · 9% CAGR over 4y
Location
Comet Holdings Limited
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsDevelops and manufactures radio frequency power systems for plasma processes and X‑ray components, modules, and CT inspection systems. Products are used for semiconductor manufacturing, industrial…
Serves B2B industrial customers, particularly electronics and semiconductor manufacturers, plus companies in automotive, aerospace and security. Targets buyers needing high-tech inspection, testing…
Financial Health
StableStable · Hiring · 6% CAGR over 3y
Location
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops and manufactures superconducting quantum computing hardware, including quantum processing units, and provides cloud-based access to quantum computers and software tools for running quantum…
Serves B2B, academic and public-sector research teams developing quantum computing applications, including organisations seeking cloud access to quantum processors or on-premise QPU hardware.
Financial Health
StableStable · -52% CAGR over 4y
Location
VARITRONIX (U.K.) LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDesigns and manufactures display modules and touch solutions for automotive and industrial applications, including TFT‑LCD, OLED and mini‑LED displays, in‑cell touch panels, cockpit display systems,…
Serves B2B customers in the automotive and industrial sectors, including vehicle OEMs, Tier 1 suppliers, industrial equipment manufacturers and major mobility market players.
Financial Health
DistressedDistressed · -65% CAGR over 4y
Location
SITEHOP LTD
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsDevelops FPGA‑based network encryption systems for securing data in transit. Products provide low‑latency, high‑throughput encryption and decryption for telecom networks, data centres, financial…
Sells to telecom operators, critical infrastructure providers, data centre and cloud operators, financial services firms, enterprise technology teams and government bodies with high-performance…
Financial Health
StrongStrong · Hiring · 157% CAGR over 1y
Location
PICTIVA LIMITED
Trajectory
1y · 2024–NowLicenses a portfolio of patents related to OLED display technology, including device structures, materials, driving circuits and manufacturing processes, to companies developing and producing OLED…
Targets established companies and new entrants in the OLED display market, including manufacturers and developers of smartphone, TV, wearable, computer, component and application-specific display…
Financial Health
Insufficient historyInsufficient history
Location
Axiomise Ltd
Trajectory
3y · 2022–NowFinancial sub-scores
Computed from 3 filingsProvides formal verification training, consulting, and engineering services for semiconductor and hardware design verification. Develops methodologies and tools for applying formal methods to…
Serves semiconductor and electronics businesses, especially design and verification engineering teams working on complex chips, IP cores, RISC-V, safety-critical or connected-device projects, plus…
Financial Health
StrongStrong · Growing, Hiring · 104% CAGR over 2y
Location
Develops trapped‑ion quantum computing hardware and software. Provides quantum computer systems, cloud access platforms, developer tools, quantum random number generation technology, and applications…
Serves enterprises, research organisations, developers and startups exploring quantum computing, particularly in computational chemistry, materials science, cybersecurity/encryption and advanced…
Location
IO TECH GROUP LIMITED
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops laser‑assisted additive manufacturing and digital printing systems for electronics production. Its technology jets and deposits polymers, metal and ceramic pastes with micron precision for…
Sells to electronics manufacturers and production teams in SMT assembly, PCB fabrication, OSAT/EMS, advanced packaging and related industrial additive manufacturing applications.
Financial Health
StableStable · Hiring · 7% CAGR over 4y
Location
I.M.D TECHNOLOGIES LTD
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsDevelops hardware and software for AI-powered edge vision systems. Designs and supplies system-on-modules, single-board computers, cameras, and AI accelerator platforms, and provides engineering…
Serves B2B OEMs and product developers building AI-powered edge vision systems, including robotics, healthcare, smart retail, smart city, smart home and automotive companies.
Financial Health
StrongStrong · Growing, Hiring · 53% CAGR over 4y
Location
Designs and manufactures modular physical vapour deposition (PVD) systems for thin‑film deposition. Supplies configurable vacuum deposition equipment, including sputtering and evaporation sources,…
Serves research laboratories, universities and industrial R&D teams working in thin-film deposition across materials science, semiconductors, photovoltaics, optics, electronics, nanomaterials and…
Location
PCB Unit Ltd
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsFinancial Health
WeakWeak
Location
DORMAN SMITH TECHNOLOGIES LIMITED
Trajectory
4y · 2022–NowFinancial sub-scores
Computed from 4 filingsFinancial Health
DistressedDistressed
Location
HEXAVES LTD
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsFinancial Health
DistressedDistressed · 0% CAGR over 1y
Location
PARTICLE ENERGY LTD
Trajectory
2y · 2024–NowFinancial sub-scores
Computed from 2 filingsFinancial Health
StableStable
Location
CX Auto Group Ltd
Trajectory
5y · 2021–NowFinancial sub-scores
Computed from 5 filingsFinancial Health
StrongStrong
Location
Standex Electronics (U.K.)
Designs and manufactures precision‑engineered electronic components including reed switches, sensors, relays, transformers, and custom magnetic components. Supplies parts for automotive, industrial,…
Serves B2B engineering and procurement teams at OEMs and manufacturers in automotive, industrial automation, test and measurement, energy and utilities, aerospace, medical and military markets.
Location
Moorfield Nanotechnology
Manufactures nanotechnology research equipment including benchtop and modular systems for physical vapour deposition (PVD), chemical vapour deposition (CVD), reactive ion etching and annealing, as…
Sells to research and development labs, universities, and advanced materials or semiconductor organisations, including scientists, engineers and lab managers working with thin-film and nanotechnology…
Location
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How London semiconductor companies work and how to sell to them
What they do
London semiconductor suppliers usually monetise expertise before volume product revenue arrives. Common models include fixed-fee design projects, non-recurring engineering charges, time-and-materials prototyping, intellectual-property licensing, royalties and component margins on specialist sensors, photonics or embedded-electronics modules. Some also run retainers for ongoing technical support, certification work or customer-specific adaptation. Pricing is shaped less by seat counts than by engineering risk, access to scarce technical staff, test-lab time and the customer's expected production pathway. A design win can create recurring revenue, but only after validation, qualification and supply-chain approval have been worked through with the buyer.
Who they sell to
Their customers are usually hardware-led businesses rather than general technology teams: electronics manufacturers, communications equipment makers, industrial automation suppliers, energy systems firms and medical-device or aerospace supply chains. Most sales start with technical directors, heads of engineering, product owners or systems architects, then move to procurement, programme management, quality and finance once the design case is credible. Smaller buyers may buy through a founder or CTO; larger buyers often require supplier onboarding, security review and staged approval. Direct sales and technical referral matter more than self-serve channels, while public-sector and defence-adjacent work tends to involve RFPs, framework-style procurement or subcontractor routes.
What they buy
Most semiconductor firms tend to spend on engineering and evidence management before general back-office software. Relevant categories include electronic design automation, simulation, test-data management, product lifecycle management, requirements tracking, secure document exchange, source-control governance and cloud compute for burst workloads. They also buy legal advice for intellectual property and contracts, export-control support, quality-management consultancy, specialist accountancy, R&D tax advice, recruitment for hardware and firmware roles, and access to laboratories, calibration services and small-batch manufacturing partners. CRM, finance systems and HR tools matter, but usually need to fit project-based revenue recognition and long customer qualification cycles.
Why and how to sell to them
Buying intent often appears when a supplier moves from consultancy into repeatable intellectual property, wins a customer programme, prepares for tape-out, hires commercial leadership, or faces a security, quality or export-control review. Cash can be lumpy, because engineering spend lands well before production revenue, so pitches that make the cost, risk and timing case clearly tend to travel further inside the account. Sellers should expect technically literate scrutiny and bring proof that maps to design assurance, confidential collaboration, audit trails or supply-chain resilience. A useful outbound angle is usually operational: fewer design rework loops, clearer customer evidence packs, cleaner handover between engineering, procurement and finance.
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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