| # | Company | Employees |
|---|---|---|
| 1 |
BAE Systemsbaesystems.com
The company provides advanced technology-led defense, aerospace, and security solutions, with a skilled workforce in over 40 countries, focusing on innovation and long-term commitment |
55,143 |
| 2 |
Rolls-Roycerolls-royce.com
Engineering excellence driving critical technologies for air, sea, and land, powering, protecting, and connecting people worldwide. |
31,649 |
| 3 |
UK Ministry of Defencegov.uk
The company works to protect the security and interests of the United Kingdom, providing necessary training, equipment, and support for the Armed Forces |
30,901 |
| 4 |
Babcock International Groupbabcockinternational.com
An international defence company providing product and service solutions to enhance customers' capabilities and assets, offering opportunities for professionals to grow |
16,474 |
| 5 |
Smiths Detectionsmithsdetection.com
Global provider of advanced threat detection and screening technologies protecting society from explosives, weapons, contraband, toxic chemicals, and narcotics. |
3,305 |
| 6 |
Ricardoricardo.com
Global consulting firm providing strategic, environmental, and engineering solutions focused on transport, energy, and climate for sustainability. |
2,888 |
| 7 |
BAE Systems Airbaesystems.com
Global leader in the development, manufacturing, and support of combat and fast jet trainer aircraft, providing solutions across the entire life cycle of the air sector with international collaboration |
2,736 |
| 8 |
Ultra Electronics Groupcobhamultra.com
Global defense and security company providing mission-critical solutions in C2ISR, underwater warfare, and intelligent sensors for government and military needs. |
2,532 |
| 9 |
Huntinghuntingplc.com
Global energy services provider to top oil and gas companies, specializing in manufacturing and distributing products for extraction Headquartered in the UK |
1,713 |
| 10 |
Royal Marinesroyalnavy.mod.uk
An elite fighting force within the Royal Navy, specializing in rapid response to global threats and security challenges, including ship-to-ship operations |
1,423 |
| 11 |
Smiths Interconnectsmithsinterconnect.com
Design and manufacture of high-reliability electronic components, microwave, optical, and RF products for aerospace, defense, medical, semiconductor, and industrial markets. |
1,090 |
| 12 |
Inmarsatviasat.com
Account closed, follow Viasat company page for satellite communications news due to acquisition. No longer posting here. |
939 |
| 13 |
Northrop Grumman UKnorthropgrumman.com
Innovative UK-based team developing next-generation security and defence technologies for Royal Navy, RAF, British Army, and UK Government, focusing on national security capabilities |
350 |
| 14 |
Eutelsat OneWebeutelsat.com
delivers ubiquitous global connectivity using a fleet of GEO and LEO satellites, combining networks for customer solutions. |
348 |
| 15 | 292 | |
| 16 |
Diploma PLCdiplomaplc.com
A dynamic distribution group providing value-add solutions in Controls, Seals, and Life Sciences sectors internationally to simplify customers' lives |
205 |
| 17 |
NATO DIANAdiana.nato.int
Locates, accelerates dual-use innovation, provides technology developers with resources, networks, expertise to address critical defense and security challenges, creates a peaceful, resilient future. |
147 |
| 18 |
Dronamicsdronamics.com
Revolutionary fixed-wing cargo UAV enables affordable, long-distance transport, opening new trade routes and revolutionizing air cargo industry |
112 |
| 19 |
Titania Ltdtitania.com
Provides real-time network visibility, vulnerability assessments, and solutions for network readiness, recovery, and resilience to protect critical infrastructure globally. |
104 |
| 20 |
MARSS Groupmarss.com
Developing AI-enabled command, control, and multi-domain surveillance solutions, integrating data from various sensors for real-time, actionable intelligence in defense and security. |
96 |
| 21 |
Hadeanhadean.com
This company develops AI-powered spatial computing applications for immersive web experiences, serving various industries and partnering with leading organizations |
72 |
| 22 |
Detego Globaldetegoglobal.com
Detego Global provides end-to-end digital forensics solutions for military, intelligence agencies, police units, and enterprises, enabling rapid intelligence acquisition and analysis |
63 |
| 23 | 50 | |
| 24 | 48 | |
| 25 |
MindLinkmindlinksoft.com
Ultra-secure chat messaging platform for classified communication in national security and defence, enabling real-time collaboration for mission-critical operations and expedited decision-making. |
45 |
| 26 |
SatVusatellitevu.com
Innovative space tech company using high-resolution thermal imaging to promote energy efficiency, reduce carbon footprint, and drive sustainability worldwide |
43 |
| 27 |
Sovereign Global Solutionsso-global.com
A European group supports African countries in enhancing sovereignty by providing strategic planning, training, logistics, and equipment for defense and security programs |
41 |
| 28 |
Universal Defence and Security Solutionsuniversal-defence.com
Global consultancy offering defence and security services to governments, militaries, businesses, and organizations, specializing in expert analysis on conflicts |
38 |
| 29 |
Spacefluxspaceflux.io
Global optical sensor network and AI platform providing sovereign space domain awareness, catalogue maintenance, and mission-critical behavioural analysis for governments and commercial operators. |
34 |
| 30 |
Telicenttelicent.io
Telicent CORE is an end-to-end-secure data platform that enables interoperable data access across trust boundaries with sophisticated indexing and access control |
26 |
| 31 |
SESP Groupsespgroup.com
A leading innovator in RF security equipment, providing jamming solutions for various applications with a focus on reliability and performance |
23 |
| 32 |
Tenacium DC
Tenacium DC helps customers overcome cybersecurity implementation challenges using their T5 Framework, R&D Labs, and upskilling approach, enhancing cyber defenses |
22 |
| 33 |
GIGAgigagroup.co.uk
Extends human life across planets and galaxies through AI-driven rocket design, defense satellites, orbital space stations, and moon bases. |
14 |
| 34 |
Value.Spacevalue.space
A tech company using satellite data and AI for global property assessments, risk analysis, and disaster prevention in commercial and infrastructure sectors |
13 |
| 35 |
TODS AEROSPACE LIMITED
An aviation & aerospace company based in London, UK, specializing in aerospace solutions, products, and services for the aviation industry |
13 |
| 36 |
Lúnasa (Infinite Orbits UK)lunasaspace.com
UK-based NewSpace company developing autonomous satellites to provide geostationary operators with asset inspection, mission lifespan extension, and end-of-life phase management services. |
9 |
| 37 |
Untriteuntrite.com
Provides AI software for national security, defence, and commercial sectors, analyzing diverse data in real-time for better decision-making and actionable intelligence. |
6 |
| 38 |
Archangel Aerospacebreezy.hr
An aerospace company deploying cutting-edge technologies to solve global challenges, including developing smart cameras and laser communication technology for remote environments |
3 |
| 39 |
Masters of Piemastersofpie.com
Innovative UK software company specializing in real-time XR collaboration solutions for Defence and Enterprise industries, integrating complex data across AR, VR, desktop, and mobile devices |
1 |
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.
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