Company lists · Data refreshed September 2026
Top 25 Security integrators based in London, United Kingdom
RevenueBase identified 542 company matches for security integrators associated with London, United Kingdom as of September 2026 and tracks 86,217 professional contacts across them, including 2,009 with verified work emails. Across the United Kingdom, London is the largest hub for this category.
This list covers company matches for security integrators 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 21, 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 security integrators 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 21, 2026 · View company records in RevenueBase | |||||
| 2 | 919 contacts → | ||||
Exact match “CIS Security is an independent security company equipped to help customers to solve the complex challenges in today’s digital, connected and regulated business world.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 3 | 847 contacts → | ||||
Exact match “Corps Security - experts in security with social value Built on over 165 years of experience, Corps provides specialist security services, across the UK, to ensure the safety of…” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 4 | 358 contacts → | ||||
Exact match “ASEL design, develop and deliver fully bespoke and integrated security solutions, seamlessly bringing together people, technology and processes to achieve results-driven outcomes.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 5 | 169 contacts → | ||||
Exact match “As a member of Mitie Group a leading facilities management and professional services company GBE Converge brings an unparalleled expertise in Fire, Security, and IT systems.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 6 | 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 21, 2026 · View company records in RevenueBase | |||||
| 7 | 153 contacts → | ||||
Exact match “For 40 years, LMG has delivered secure, resilient and proven digital infrastructure solutions across the built environment.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 8 | 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 21, 2026 · View company records in RevenueBase | |||||
| 9 | 115 contacts → | ||||
Exact match “The Infinigate Group is a value-added distributor, fully committed to sustainable, leading-edge cybersecurity solutions.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 10 | 97 contacts → | ||||
Exact match “As an independent IT security specialist, Caretower provide comprehensive solutions to individual problems, thus allowing our recommendations to be unbiased.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 11 | 82 contacts → | ||||
Exact match “Crossover is a leading audiovisual systems integrator – we deliver AV that’s high quality, powerful, simple to use, and reliable.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 12 | 80 contacts → | ||||
Exact match “Nephos Technologies is an independent data systems integrator, specialising in helping organisations transform the way they store, manage and protect their data.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 13 | 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 21, 2026 · View company records in RevenueBase | |||||
| 14 | 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 21, 2026 · View company records in RevenueBase | |||||
| 15 | 60 contacts → | ||||
Exact match “Garrison is a London-based cybersecurity company founded in 2014 by David Garfield (CEO) and Henry Harrison (Chief Scientist).” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 16 | 58 contacts → | ||||
Exact match “Black Diamond Security - Safeguarding Your World.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 17 | 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 21, 2026 · View company records in RevenueBase | |||||
| 18 | 50 contacts → | ||||
Exact match “Sensetech Systems Ltd is an LPS1014 Accredited independent Fire Alarm, Security and Structured Data Cabling Company.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 19 | 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 21, 2026 · View company records in RevenueBase | |||||
| 20 | 44 contacts → | ||||
Exact match “CornerStone is an award winning, independent, security and digital building consulting firm with headquarters in the UK.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 21 | 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 21, 2026 · View company records in RevenueBase | |||||
| 22 | 41 contacts → | ||||
Exact match “SMC are a leading custom electronic system design, installation and aftercare company.” Recorded in the RevenueBase company graph · Sep 21, 2026 · View company records in RevenueBase | |||||
| 23 | 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 21, 2026 · View company records in RevenueBase | |||||
| 24 | 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 21, 2026 · View company records in RevenueBase | |||||
| 25 | 37 contacts → | ||||
Exact match “We are systems integrators.” Recorded in the RevenueBase company graph · Sep 21, 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 “security integrators”. 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 542 security integrators based in London, United Kingdom
See the full list, filter by size, metro and specialty, and access 2,009 tracked professional contacts with verified work emails. Direct dials are available where recorded.
Free signup · no credit card
Security integrators based in London, United Kingdom at a glance
As of Sep 21, 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 542 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 “security integrators” 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 2,009 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 21, 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.
Security integrators by metro in the United Kingdom
- Security integrators in Manchester63
- Security integrators in Birmingham53
- Security integrators in Glasgow44
- Security integrators in Bristol36
- Security integrators in Leeds35
- Security integrators in Nottingham34
- Security integrators in Belfast28
- Security integrators in Leicester26
- Security integrators in Sheffield26
- Security integrators in Southampton26
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 “security integrators”; each Exact match badge shows search membership, not an individual similarity or quality score.
How many security integrators are there based in London, United Kingdom?
RevenueBase identified 542 company matches for security integrators 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 security integrators?
London leads the United Kingdom with 542 company records, followed by Manchester (63) and Birmingham (53).
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 2,009 professional contacts with verified work emails tracked across these 542 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 21, 2026.
Ready to reach these companies? Verified emails and direct dials for all 542 security integrators based in London, United Kingdom. Start with a free account, no credit card.
Download this list →Related lists
Security integrators by geography
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil
- Security integrators based in Belo Horizonte, Brazil
- Security integrators based in Campinas, Brazil
- Security integrators based in Curitiba, Brazil
- Security integrators based in Fortaleza, Brazil
- Security integrators based in Porto Alegre, Brazil
- Security integrators based in Rio De Janeiro, Brazil
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
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil
Company intelligence · public preview
Top 25 security integrators 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 542 matching company records for security integrators based in London, United Kingdom, with 86,217 tracked contacts and 2,009 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 21, 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 security integrators 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 |  CIS Security Limitedcis-security.co.ukHQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 919 contacts → |
“CIS Security is an independent security company equipped to help customers to solve the complex challenges in today’s digital, connected and regulated business world.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 |  Corps Securitycorpssecurity.co.ukHQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 847 contacts → |
“Corps Security - experts in security with social value Built on over 165 years of experience, Corps provides specialist security services, across the UK, to ensure the safety of…” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 | HQ: London, United KingdomReported employees: 5,001-10,000 | London, United Kingdom | 5,001-10,000 | Exact match | 358 contacts → |
“ASEL design, develop and deliver fully bespoke and integrated security solutions, seamlessly bringing together people, technology and processes to achieve results-driven outcomes.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 |  GBE Converge Part Of Mitiegbeconverge.comHQ: London, United KingdomReported employees: 501-1,000 | London, United Kingdom | 501-1,000 | Exact match | 169 contacts → |
“As a member of Mitie Group a leading facilities management and professional services company GBE Converge brings an unparalleled expertise in Fire, Security, and IT systems.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 |  LMG Lmgiq.comlmgiq.comHQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 153 contacts → |
“For 40 years, LMG has delivered secure, resilient and proven digital infrastructure solutions across the built environment.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 |  Infinigate UK & Irelandinfinigate.comHQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 115 contacts → |
“The Infinigate Group is a value-added distributor, fully committed to sustainable, leading-edge cybersecurity solutions.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 |  Caretower An Integrity360 Companyintegrity360.comHQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 97 contacts → |
“As an independent IT security specialist, Caretower provide comprehensive solutions to individual problems, thus allowing our recommendations to be unbiased.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 |  Crossovercrossover-av.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 82 contacts → |
“Crossover is a leading audiovisual systems integrator – we deliver AV that’s high quality, powerful, simple to use, and reliable.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 |  Nephos Technologiesnephostechnologies.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 80 contacts → |
“Nephos Technologies is an independent data systems integrator, specialising in helping organisations transform the way they store, manage and protect their data.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 |  Garrison NOW A Part Of Everfoxgarrison.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 60 contacts → |
“Garrison is a London-based cybersecurity company founded in 2014 by David Garfield (CEO) and Henry Harrison (Chief Scientist).” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 |  Sensetech Systems LTDsensetechsystems.co.ukHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 50 contacts → |
“Sensetech Systems Ltd is an LPS1014 Accredited independent Fire Alarm, Security and Structured Data Cabling Company.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 |  Cornerstonecornerstonegrg.co.ukHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 44 contacts → |
“CornerStone is an award winning, independent, security and digital building consulting firm with headquarters in the UK.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 |  SMC Smart Homessmc-uk.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 41 contacts → |
“SMC are a leading custom electronic system design, installation and aftercare company.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 |  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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 |  Link Media Systemslinkmediasystems.comHQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 37 contacts → |
“We are systems integrators.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 542 company matches
Build a targeted audience, find relevant contacts and export available records to your workflow.
Free signup · 500 credits · limited free results
Security integrators: dataset insights
September 21, 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
538 records in the displayed employee bands.
4 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 542 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 21, 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 ↗
Security integrators by metro in the United Kingdom
- Security integrators in Manchester63
- Security integrators in Birmingham53
- Security integrators in Glasgow44
- Security integrators in Bristol36
- Security integrators in Leeds35
- Security integrators in Nottingham34
- Security integrators in Belfast28
- Security integrators in Leicester26
- Security integrators in Sheffield26
- Security integrators in Southampton26
Questions about this company list
What does Exact match mean for security integrators?
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 security integrators did RevenueBase find based in London, United Kingdom?
The saved snapshot records 542 matching company records, 86,217 tracked contacts and 2,009 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 21, 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
Security integrators by geography
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil
- Security integrators based in Belo Horizonte, Brazil
- Security integrators based in Campinas, Brazil
- Security integrators based in Curitiba, Brazil
- Security integrators based in Fortaleza, Brazil
- Security integrators based in Porto Alegre, Brazil
- Security integrators based in Rio De Janeiro, Brazil
Cite this list
RevenueBase Data Team. Top 25 security integrators based in London, United Kingdom. Snapshot: September 21, 2026. https://revenuebase.ai/companies/security-integrators/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
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil
Company intelligence · public preview
Top 25 security integrators based in London, United Kingdom
RevenueBase records 542 matching company records for security integrators based in London, United Kingdom, with 86,217 tracked contacts and 2,009 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 21, 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 security integrators 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 | CIS Security Limitedcis-security.co.uk HQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 919 contacts → |
“CIS Security is an independent security company equipped to help customers to solve the complex challenges in today’s digital, connected and regulated business world.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 | Corps Securitycorpssecurity.co.uk HQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 847 contacts → |
“Corps Security - experts in security with social value Built on over 165 years of experience, Corps provides specialist security services, across the UK, to ensure the safety of…” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 | HQ: London, United KingdomReported employees: 5,001-10,000 | London, United Kingdom | 5,001-10,000 | Exact match | 358 contacts → |
“ASEL design, develop and deliver fully bespoke and integrated security solutions, seamlessly bringing together people, technology and processes to achieve results-driven outcomes.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 | GBE Converge Part Of Mitiegbeconverge.com HQ: London, United KingdomReported employees: 501-1,000 | London, United Kingdom | 501-1,000 | Exact match | 169 contacts → |
“As a member of Mitie Group a leading facilities management and professional services company GBE Converge brings an unparalleled expertise in Fire, Security, and IT systems.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 | LMG Lmgiq.comlmgiq.com HQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 153 contacts → |
“For 40 years, LMG has delivered secure, resilient and proven digital infrastructure solutions across the built environment.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 | Infinigate UK & Irelandinfinigate.com HQ: London, United KingdomReported employees: 1,001-5,000 | London, United Kingdom | 1,001-5,000 | Exact match | 115 contacts → |
“The Infinigate Group is a value-added distributor, fully committed to sustainable, leading-edge cybersecurity solutions.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 | Caretower An Integrity360 Companyintegrity360.com HQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 97 contacts → |
“As an independent IT security specialist, Caretower provide comprehensive solutions to individual problems, thus allowing our recommendations to be unbiased.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 | Crossovercrossover-av.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 82 contacts → |
“Crossover is a leading audiovisual systems integrator – we deliver AV that’s high quality, powerful, simple to use, and reliable.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 | Nephos Technologiesnephostechnologies.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 80 contacts → |
“Nephos Technologies is an independent data systems integrator, specialising in helping organisations transform the way they store, manage and protect their data.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 | Garrison NOW A Part Of Everfoxgarrison.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 60 contacts → |
“Garrison is a London-based cybersecurity company founded in 2014 by David Garfield (CEO) and Henry Harrison (Chief Scientist).” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 | Sensetech Systems LTDsensetechsystems.co.uk HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 50 contacts → |
“Sensetech Systems Ltd is an LPS1014 Accredited independent Fire Alarm, Security and Structured Data Cabling Company.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 | Cornerstonecornerstonegrg.co.uk HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 44 contacts → |
“CornerStone is an award winning, independent, security and digital building consulting firm with headquarters in the UK.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 | SMC Smart Homessmc-uk.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 41 contacts → |
“SMC are a leading custom electronic system design, installation and aftercare company.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 | 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 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 | Link Media Systemslinkmediasystems.com HQ: London, United KingdomReported employees: 51-200 | London, United Kingdom | 51-200 | Exact match | 37 contacts → |
“We are systems integrators.” Recorded description excerpt · September 21, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 542 company matches
Build a targeted audience, find relevant contacts and export available records to your workflow.
Free signup · 500 credits · limited free results
Security integrators: dataset insights
September 21, 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
538 records in the displayed employee bands.
4 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 542 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 21, 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 ↗
Security integrators by metro in the United Kingdom
- Security integrators in Manchester63
- Security integrators in Birmingham53
- Security integrators in Glasgow44
- Security integrators in Bristol36
- Security integrators in Leeds35
- Security integrators in Nottingham34
- Security integrators in Belfast28
- Security integrators in Leicester26
- Security integrators in Sheffield26
- Security integrators in Southampton26
Questions about this company list
What does Exact match mean for security integrators?
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 security integrators did RevenueBase find based in London, United Kingdom?
The saved snapshot records 542 matching company records, 86,217 tracked contacts and 2,009 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 21, 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
Security integrators by geography
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil
- Security integrators based in Belo Horizonte, Brazil
- Security integrators based in Campinas, Brazil
- Security integrators based in Curitiba, Brazil
- Security integrators based in Fortaleza, Brazil
- Security integrators based in Porto Alegre, Brazil
- Security integrators based in Rio De Janeiro, Brazil
Cite this list
RevenueBase Data Team. Top 25 security integrators based in London, United Kingdom. Snapshot: September 21, 2026. https://revenuebase.ai/companies/security-integrators/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
- Security integrators based in Buenos Aires, Argentina
- Security integrators based in Brisbane, Australia
- Security integrators based in Melbourne, Australia
- Security integrators based in Perth, Australia
- Security integrators based in Sydney, Australia
- Security integrators based in Barueri, Brazil