Company lists · Data refreshed September 2026
Top 25 Infrastructure protection companies based in London, United Kingdom
RevenueBase identified 250 company matches for infrastructure protection companies associated with London, United Kingdom as of September 2026 and tracks 82,768 professional contacts across them, including 858 with verified work emails. Across the United Kingdom, London is the largest hub for this category.
This list covers company matches for infrastructure protection companies associated with London, United Kingdom, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 20, 2026.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest infrastructure protection companies based in London, United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 79,699 contacts → | ||||
Exact match “G4S is a leading security and facility services company that provides proactive security services and cutting-edge smart technology to deliver tailored, integrated security…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 2 | 159 contacts → | ||||
Exact match “QCIC is an award-winning global engineering firm specialising in designing, building and running security systems.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 3 | 137 contacts → | ||||
Exact match “The Keyholding Company are a tech-enabled mobile security services company, specialising in alarm response, mobile patrols, locks and unlocks, emergency and temporary guarding…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 4 | 136 contacts → | ||||
Exact match “PRÆSIDIAD is a world market leader of force protection solutions,integrated perimeter security systems and industrial mesh production and fencing products.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 5 | 105 contacts → | ||||
Exact match “Cybersecurity specialists providing technology and telecoms solutions that gives you the leadership, experience and resilience you need to build and secure the future of work.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 6 | 64 contacts → | ||||
Exact match “City Security Services (CSS) have more than 25 years’ experience within the corporate security, public sector, education and social housing markets delivering manned guarding…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 7 | 61 contacts → | ||||
Exact match “WLS (West London Security) has been providing security and solutions to London's homes and businesses for over 40 years.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 8 | 58 contacts → | ||||
Exact match “Black Diamond Security - Safeguarding Your World.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 9 | 51 contacts → | ||||
Exact match “Established in Custom Intelligent Security is a technology driven ISO27001 & NSi Gold Accredited independent electronic security specialist with a proven track record of…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 10 | 49 contacts → | ||||
Exact match “Electranet’s mission is to be a preferred partner to the public and private sectors, bringing competitively priced, secure and innovative solutions to the market.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 11 | 43 contacts → | ||||
Exact match “AK9 Security and FM Solutions offers comprehensive security solutions for businesses, governmental organizations, and residential areas.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 12 | 39 contacts → | ||||
Exact match “Gratte Brothers is an experienced provider of integrated security solutions, which are Built on Strong Values and ultimately deliver a measurable return on investment.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 13 | 39 contacts → | ||||
Exact match “Universal Security Systems Limited is a specialist provider of installation and maintenance services for all types of security systems including Access Control, Closed Circuit…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 14 | 34 contacts → | ||||
Exact match “Our elite teams offer bespoke, integrated security solutions that adapt and react to the evolving threat landscape.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 15 | 32 contacts → | ||||
Exact match “CYB3R Group, is a leading provider of comprehensive Cyber Security, IT and Communications Solutions.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 16 | 27 contacts → | ||||
Exact match “CCTV and Access Control Service and installation specialists Established in 1993 DS Security prides itself on customer service.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 17 | 25 contacts → | ||||
Exact match “Encode is now part of Obrela Security Industries collectively delivering cutting edge Cyber Security Services, empowering organizations to better protect against cyber threats.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 18 | 24 contacts → | ||||
Exact match “Nanjgel Solutions is focused on delivering the best IT security for businesses.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 19 | 23 contacts → | ||||
Exact match “Who are you… Most likely you are a Workplace or IT Professional with a lot on your plate including physical electronic security systems, such as - Access control - CCTV - Intruder…” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 20 | 20 contacts → | ||||
Exact match “The Dennis Johns Service Group is a forward thinking group of companies providing, Electrical, CCTV and Access Control, installation and maintenance contracting services.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 21 | 20 contacts → | ||||
Exact match “Formed in 2018, NGS (UK) Ltd are independent, Next Generation Security trusted advisors, providing all-encompassing solutions from the perimeter to the endpoint.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 22 | 19 contacts → | ||||
Exact match “The Portmarnock Group was built from years of experience, hard work and a genuine passion for doing security differently.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 23 | 18 contacts → | ||||
Exact match “Infosec K2K safeguards your organisation’s most valuable assets with tailored cybersecurity solutions.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 24 | 17 contacts → | ||||
Exact match “We are a leading cybersecurity services organization with more than a decade of proven expertise in consulting, solution implementation and managed services.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
| 25 | 17 contacts → | ||||
Exact match “We are a London based specialist supplier of cyber defence solution and information security services.” Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase | |||||
RevenueBase SmartSearch
Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.
This list uses Exact for “infrastructure protection companies”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.
Showing 25 of 250 infrastructure protection companies based in London, United Kingdom
See the full list, filter by size, metro and specialty, and access 858 tracked professional contacts with verified work emails. Direct dials are available where recorded.
Free signup · no credit card
Infrastructure protection companies based in London, United Kingdom at a glance
As of Sep 20, 2026Companies by employee count
Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 250 companies.
How this list was built
The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
- What qualifies
- Company records associated with London, United Kingdom whose business descriptions match “infrastructure protection companies” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
- RevenueBase SmartSearch
- Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
- Public preview
- The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
- Match quality
- RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every displayed company carries at least one verified work email. RevenueBase tracks 858 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 20, 2026. Lists refresh periodically as the graph is re-checked.
- Record context
- Company records and descriptions can change. Check the company's website for its current services and locations.
Infrastructure protection companies by metro in the United Kingdom
Frequently asked
What is RevenueBase SmartSearch?
RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “infrastructure protection companies”; each Exact match badge shows search membership, not an individual similarity or quality score.
How many infrastructure protection companies are there based in London, United Kingdom?
RevenueBase identified 250 company matches for infrastructure protection companies associated with London, United Kingdom as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.
What is the largest company on this list?
G4s tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.
Which city in the United Kingdom has the most infrastructure protection companies?
London leads the United Kingdom with 250 company records, followed by Manchester (32) and Birmingham (25).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 858 professional contacts with verified work emails tracked across these 250 companies; direct dials are available where recorded.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 20, 2026.
Ready to reach these companies? Verified emails and direct dials for all 250 infrastructure protection companies based in London, United Kingdom. Start with a free account, no credit card.
Download this list →Related lists
Infrastructure protection companies by geography
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil
- Infrastructure protection companies based in Porto Alegre, Brazil
- Infrastructure protection companies based in Rio De Janeiro, Brazil
- Infrastructure protection companies based in Sao Paulo, Brazil
- Infrastructure protection companies based in Calgary, Canada
- Infrastructure protection companies based in Montreal, Canada
- Infrastructure protection companies based in Toronto, Canada
About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil
Company intelligence · public preview
Top 25 infrastructure protection companies based in London, United Kingdom
Find companies in any niche.
Describe the businesses you want in your own words. RevenueBase SmartSearch matches company descriptions by meaning.
RevenueBase records 250 matching company records for infrastructure protection companies based in London, United Kingdom, with 82,768 tracked contacts and 858 verified work emails.
This public preview shows 25 selected records ordered by tracked contacts. RevenueBase SmartSearch finds company descriptions that match by meaning at Exact. Snapshot: September 20, 2026.
RevenueBase compiles business descriptions for niche-company discovery; each row shows a recorded excerpt where available. Adapt this search to find the companies and contacts you want.
Top 25 infrastructure protection companies based in London, United Kingdom
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
| # | Company | Headquarters on record | Reported employees | RevenueBase SmartSearch | Tracked contacts |
|---|---|---|---|---|---|
| 1 |  G4sg4s.comHQ: London, United KingdomReported employees: 10001+ | London, United Kingdom | 10001+ | Exact match | 79,699 contacts → |
“G4S is a leading security and facility services company that provides proactive security services and cutting-edge smart technology to deliver tailored, integrated security…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 |  QCICqcic-group.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 159 contacts → |
“QCIC is an award-winning global engineering firm specialising in designing, building and running security systems.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 |  The Keyholding Companykeyholding.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 137 contacts → |
“The Keyholding Company are a tech-enabled mobile security services company, specialising in alarm response, mobile patrols, locks and unlocks, emergency and temporary guarding…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 |  Præsidiadpraesidiad.comHQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 136 contacts → |
“PRÆSIDIAD is a world market leader of force protection solutions,integrated perimeter security systems and industrial mesh production and fencing products.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 |  Conoscoconosco.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 105 contacts → |
“Cybersecurity specialists providing technology and telecoms solutions that gives you the leadership, experience and resilience you need to build and secure the future of work.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 |  City Security Services Part Of City Group Securitycitysecurity.org.ukHQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 64 contacts → |
“City Security Services (CSS) have more than 25 years’ experience within the corporate security, public sector, education and social housing markets delivering manned guarding…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 |  WLSwestlondonsecurity.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 61 contacts → |
“WLS (West London Security) has been providing security and solutions to London's homes and businesses for over 40 years.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 |  Black Diamond Securityblackdiamondsecurity.co.ukHQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 58 contacts → |
“Black Diamond Security - Safeguarding Your World.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 |  Custom Intelligent Securitycustomsecurity.tvHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 51 contacts → |
“Established in Custom Intelligent Security is a technology driven ISO27001 & NSi Gold Accredited independent electronic security specialist with a proven track record of…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 |  Electranet UK Limitedelectranetuk.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 49 contacts → |
“Electranet’s mission is to be a preferred partner to the public and private sectors, bringing competitively priced, secure and innovative solutions to the market.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 |  Ak9 Security And FM Solutions LTDak9security.comHQ: London, United KingdomReported employees: 501-1,000 | London, United Kingdom | 501-1,000 | Exact match | 43 contacts → |
“AK9 Security and FM Solutions offers comprehensive security solutions for businesses, governmental organizations, and residential areas.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 | HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 39 contacts → |
“Gratte Brothers is an experienced provider of integrated security solutions, which are Built on Strong Values and ultimately deliver a measurable return on investment.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 |  Universal Security Systems LTDconvergint.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 39 contacts → |
“Universal Security Systems Limited is a specialist provider of installation and maintenance services for all types of security systems including Access Control, Closed Circuit…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 |  Team Fusion LTDteamfusion.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 34 contacts → |
“Our elite teams offer bespoke, integrated security solutions that adapt and react to the evolving threat landscape.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 |  Cyb3rcyb3rsolutrions.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 32 contacts → |
“CYB3R Group, is a leading provider of comprehensive Cyber Security, IT and Communications Solutions.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 |  DS Security Group LTDdssecurity.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 27 contacts → |
“CCTV and Access Control Service and installation specialists Established in 1993 DS Security prides itself on customer service.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 |  Encodeobrela.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 25 contacts → |
“Encode is now part of Obrela Security Industries collectively delivering cutting edge Cyber Security Services, empowering organizations to better protect against cyber threats.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 |  Nanjgel Solutionsnanjgel.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 24 contacts → |
“Nanjgel Solutions is focused on delivering the best IT security for businesses.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 |  Welcome Gatewelcomegate.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 23 contacts → |
“Who are you… Most likely you are a Workplace or IT Professional with a lot on your plate including physical electronic security systems, such as - Access control - CCTV - Intruder…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 |  Dennis Johns Service Groupdennisjohns.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 20 contacts → |
“The Dennis Johns Service Group is a forward thinking group of companies providing, Electrical, CCTV and Access Control, installation and maintenance contracting services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 |  NGS Next Generation Securityngsuk.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 20 contacts → |
“Formed in 2018, NGS (UK) Ltd are independent, Next Generation Security trusted advisors, providing all-encompassing solutions from the perimeter to the endpoint.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 |  The Portmarnock Groupportmarnockgroup.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 19 contacts → |
“The Portmarnock Group was built from years of experience, hard work and a genuine passion for doing security differently.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 |  Infosec K2kinfoseck2k.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 18 contacts → |
“Infosec K2K safeguards your organisation’s most valuable assets with tailored cybersecurity solutions.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 |  Sinevissinevis.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 17 contacts → |
“We are a leading cybersecurity services organization with more than a decade of proven expertise in consulting, solution implementation and managed services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 | HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 17 contacts → |
“We are a London based specialist supplier of cyber defence solution and information security services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 250 company matches
Build a targeted audience, find relevant contacts and export available records to your workflow.
Free signup · 500 credits · limited free results
Infrastructure protection companies: dataset insights
September 20, 2026These summaries describe recorded coverage in this saved dataset. This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Reported company sizes
247 records in the displayed employee bands.
3 matching records are outside the displayed bands or do not have a displayed size. Bars show shares of the displayed bands.
Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 250 companies.
How this company list was built
Describe a niche in your own words: companies installing commercial solar, or manufacturers of sustainable packaging. RevenueBase SmartSearch finds companies whose compiled business descriptions match by meaning. This list is one saved example to adapt.
Where the company descriptions come from
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
RevenueBase SmartSearch matching settings
- Exact
- Closest fits to the business described.
- Similar
- Similar businesses with a wider range of fits.
- Related
- Related businesses in and around the category.
- Broad
- A broader set of businesses connected to the description.
RevenueBase SmartSearch · Exact match identifies inclusion in this search's closest semantic matching setting. It is not a per-company confidence score, a literal keyword match, or a quality endorsement.
Selection, ordering and scope
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Recorded company descriptions support research; check company websites for current services. The selected preview is ordered by tracked contacts and is not a list of the best service providers.
Snapshot: September 20, 2026.
RevenueBase is a B2B data infrastructure company. Its September 3, 2026 published methodology describes a graph of 60 million companies and 398.9 million professional contacts; these platform figures differ from this page's totals. Published methodology ↗
Infrastructure protection companies by metro in the United Kingdom
Questions about this company list
What does Exact match mean for infrastructure protection companies?
The separate RevenueBase SmartSearch column identifies inclusion at the closest semantic matching preset. It is not a literal keyword match, a per-company confidence score or a quality endorsement. Changing the search form opens a new search in RevenueBase; it does not reclassify these saved rows.
How many infrastructure protection companies did RevenueBase find based in London, United Kingdom?
The saved snapshot records 250 matching company records, 82,768 tracked contacts and 858 verified emails. The public preview displays 25 selected records.
Where do the company descriptions come from?
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
How are the public companies ordered?
The selected public records are ordered by contacts tracked in RevenueBase, highest first. Contact coverage is a prospecting measure, not an assessment of the company's services or quality.
How can I get contact information?
Select a company's contact count to open its filtered contacts in RevenueBase. Free signup is required and includes 500 credits and limited free results. Verified emails, direct dials and mobile numbers depend on available coverage.
How current is this list?
Snapshot: September 20, 2026. Review each company's website for current services and locations. A recorded business description does not establish that every company offers every service named in the search.
What do headquarters and employee bands mean?
These are recorded company-level fields, rather than a map of every branch or a count of specialists. Missing headquarters or employee bands are labeled; older records may show a location separately from recorded headquarters.
Build your next target company list
Adapt this niche search and work with available contacts in RevenueBase.
Related lists
Infrastructure protection companies by geography
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil
- Infrastructure protection companies based in Porto Alegre, Brazil
- Infrastructure protection companies based in Rio De Janeiro, Brazil
- Infrastructure protection companies based in Sao Paulo, Brazil
- Infrastructure protection companies based in Calgary, Canada
- Infrastructure protection companies based in Montreal, Canada
- Infrastructure protection companies based in Toronto, Canada
Cite this list
RevenueBase Data Team. Top 25 infrastructure protection companies based in London, United Kingdom. Snapshot: September 20, 2026. https://revenuebase.ai/companies/infrastructure-protection-companies/united-kingdom/london.
This is a selected public preview of saved company records, rather than an independently verified census. Open the source page ↗
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil
Company intelligence · public preview
Top 25 infrastructure protection companies based in London, United Kingdom
RevenueBase records 250 matching company records for infrastructure protection companies based in London, United Kingdom, with 82,768 tracked contacts and 858 verified work emails.
This public preview shows 25 selected records ordered by tracked contacts. RevenueBase SmartSearch finds company descriptions that match by meaning at Exact. Snapshot: September 20, 2026.
RevenueBase compiles business descriptions for niche-company discovery; each row shows a recorded excerpt where available. Adapt this search to find the companies and contacts you want.
Top 25 infrastructure protection companies based in London, United Kingdom
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
| # | Company | Headquarters on record | Reported employees | RevenueBase SmartSearch | Tracked contacts |
|---|---|---|---|---|---|
| 1 | G4sg4s.com HQ: London, United KingdomReported employees: 10001+ | London, United Kingdom | 10001+ | Exact match | 79,699 contacts → |
“G4S is a leading security and facility services company that provides proactive security services and cutting-edge smart technology to deliver tailored, integrated security…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 | QCICqcic-group.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 159 contacts → |
“QCIC is an award-winning global engineering firm specialising in designing, building and running security systems.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 | The Keyholding Companykeyholding.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 137 contacts → |
“The Keyholding Company are a tech-enabled mobile security services company, specialising in alarm response, mobile patrols, locks and unlocks, emergency and temporary guarding…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 | Præsidiadpraesidiad.com HQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 136 contacts → |
“PRÆSIDIAD is a world market leader of force protection solutions,integrated perimeter security systems and industrial mesh production and fencing products.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 | Conoscoconosco.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 105 contacts → |
“Cybersecurity specialists providing technology and telecoms solutions that gives you the leadership, experience and resilience you need to build and secure the future of work.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 | City Security Services Part Of City Group Securitycitysecurity.org.uk HQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 64 contacts → |
“City Security Services (CSS) have more than 25 years’ experience within the corporate security, public sector, education and social housing markets delivering manned guarding…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 | WLSwestlondonsecurity.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 61 contacts → |
“WLS (West London Security) has been providing security and solutions to London's homes and businesses for over 40 years.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 | Black Diamond Securityblackdiamondsecurity.co.uk HQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 58 contacts → |
“Black Diamond Security - Safeguarding Your World.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 | Custom Intelligent Securitycustomsecurity.tv HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 51 contacts → |
“Established in Custom Intelligent Security is a technology driven ISO27001 & NSi Gold Accredited independent electronic security specialist with a proven track record of…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 | Electranet UK Limitedelectranetuk.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 49 contacts → |
“Electranet’s mission is to be a preferred partner to the public and private sectors, bringing competitively priced, secure and innovative solutions to the market.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 | Ak9 Security And FM Solutions LTDak9security.com HQ: London, United KingdomReported employees: 501-1,000 | London, United Kingdom | 501-1,000 | Exact match | 43 contacts → |
“AK9 Security and FM Solutions offers comprehensive security solutions for businesses, governmental organizations, and residential areas.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 | HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 39 contacts → |
“Gratte Brothers is an experienced provider of integrated security solutions, which are Built on Strong Values and ultimately deliver a measurable return on investment.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 | Universal Security Systems LTDconvergint.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 39 contacts → |
“Universal Security Systems Limited is a specialist provider of installation and maintenance services for all types of security systems including Access Control, Closed Circuit…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 | Team Fusion LTDteamfusion.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 34 contacts → |
“Our elite teams offer bespoke, integrated security solutions that adapt and react to the evolving threat landscape.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 | Cyb3rcyb3rsolutrions.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 32 contacts → |
“CYB3R Group, is a leading provider of comprehensive Cyber Security, IT and Communications Solutions.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 | DS Security Group LTDdssecurity.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 27 contacts → |
“CCTV and Access Control Service and installation specialists Established in 1993 DS Security prides itself on customer service.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 | Encodeobrela.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 25 contacts → |
“Encode is now part of Obrela Security Industries collectively delivering cutting edge Cyber Security Services, empowering organizations to better protect against cyber threats.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 | Nanjgel Solutionsnanjgel.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 24 contacts → |
“Nanjgel Solutions is focused on delivering the best IT security for businesses.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 | Welcome Gatewelcomegate.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 23 contacts → |
“Who are you… Most likely you are a Workplace or IT Professional with a lot on your plate including physical electronic security systems, such as - Access control - CCTV - Intruder…” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 | Dennis Johns Service Groupdennisjohns.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 20 contacts → |
“The Dennis Johns Service Group is a forward thinking group of companies providing, Electrical, CCTV and Access Control, installation and maintenance contracting services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 | NGS Next Generation Securityngsuk.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 20 contacts → |
“Formed in 2018, NGS (UK) Ltd are independent, Next Generation Security trusted advisors, providing all-encompassing solutions from the perimeter to the endpoint.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 | The Portmarnock Groupportmarnockgroup.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 19 contacts → |
“The Portmarnock Group was built from years of experience, hard work and a genuine passion for doing security differently.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 | Infosec K2kinfoseck2k.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 18 contacts → |
“Infosec K2K safeguards your organisation’s most valuable assets with tailored cybersecurity solutions.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 | Sinevissinevis.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 17 contacts → |
“We are a leading cybersecurity services organization with more than a decade of proven expertise in consulting, solution implementation and managed services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 | HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 17 contacts → |
“We are a London based specialist supplier of cyber defence solution and information security services.” Recorded description excerpt · September 20, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 250 company matches
Build a targeted audience, find relevant contacts and export available records to your workflow.
Free signup · 500 credits · limited free results
Infrastructure protection companies: dataset insights
September 20, 2026These summaries describe recorded coverage in this saved dataset. This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Reported company sizes
247 records in the displayed employee bands.
3 matching records are outside the displayed bands or do not have a displayed size. Bars show shares of the displayed bands.
Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 250 companies.
How this company list was built
Describe a niche in your own words: companies installing commercial solar, or manufacturers of sustainable packaging. RevenueBase SmartSearch finds companies whose compiled business descriptions match by meaning. This list is one saved example to adapt.
Where the company descriptions come from
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
RevenueBase SmartSearch matching settings
- Exact
- Closest fits to the business described.
- Similar
- Similar businesses with a wider range of fits.
- Related
- Related businesses in and around the category.
- Broad
- A broader set of businesses connected to the description.
RevenueBase SmartSearch · Exact match identifies inclusion in this search's closest semantic matching setting. It is not a per-company confidence score, a literal keyword match, or a quality endorsement.
Selection, ordering and scope
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Recorded company descriptions support research; check company websites for current services. The selected preview is ordered by tracked contacts and is not a list of the best service providers.
Snapshot: September 20, 2026.
RevenueBase is a B2B data infrastructure company. Its September 3, 2026 published methodology describes a graph of 60 million companies and 398.9 million professional contacts; these platform figures differ from this page's totals. Published methodology ↗
Infrastructure protection companies by metro in the United Kingdom
Questions about this company list
What does Exact match mean for infrastructure protection companies?
The separate RevenueBase SmartSearch column identifies inclusion at the closest semantic matching preset. It is not a literal keyword match, a per-company confidence score or a quality endorsement. Changing the search form opens a new search in RevenueBase; it does not reclassify these saved rows.
How many infrastructure protection companies did RevenueBase find based in London, United Kingdom?
The saved snapshot records 250 matching company records, 82,768 tracked contacts and 858 verified emails. The public preview displays 25 selected records.
Where do the company descriptions come from?
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
How are the public companies ordered?
The selected public records are ordered by contacts tracked in RevenueBase, highest first. Contact coverage is a prospecting measure, not an assessment of the company's services or quality.
How can I get contact information?
Select a company's contact count to open its filtered contacts in RevenueBase. Free signup is required and includes 500 credits and limited free results. Verified emails, direct dials and mobile numbers depend on available coverage.
How current is this list?
Snapshot: September 20, 2026. Review each company's website for current services and locations. A recorded business description does not establish that every company offers every service named in the search.
What do headquarters and employee bands mean?
These are recorded company-level fields, rather than a map of every branch or a count of specialists. Missing headquarters or employee bands are labeled; older records may show a location separately from recorded headquarters.
Build your next target company list
Adapt this niche search and work with available contacts in RevenueBase.
Related lists
Infrastructure protection companies by geography
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil
- Infrastructure protection companies based in Porto Alegre, Brazil
- Infrastructure protection companies based in Rio De Janeiro, Brazil
- Infrastructure protection companies based in Sao Paulo, Brazil
- Infrastructure protection companies based in Calgary, Canada
- Infrastructure protection companies based in Montreal, Canada
- Infrastructure protection companies based in Toronto, Canada
Cite this list
RevenueBase Data Team. Top 25 infrastructure protection companies based in London, United Kingdom. Snapshot: September 20, 2026. https://revenuebase.ai/companies/infrastructure-protection-companies/united-kingdom/london.
This is a selected public preview of saved company records, rather than an independently verified census. Open the source page ↗
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Infrastructure protection companies based in Melbourne, Australia
- Infrastructure protection companies based in Sydney, Australia
- Infrastructure protection companies based in Belo Horizonte, Brazil
- Infrastructure protection companies based in Campinas, Brazil
- Infrastructure protection companies based in Curitiba, Brazil
- Infrastructure protection companies based in Fortaleza, Brazil