The top 50 UK security companies, 2026
The UK's biggest security companies — guarding, systems, cash services and specialist security — ranked by the turnover in their own filed Companies House accounts. UK operating entities only (the global G4S filing is not a UK business), with manufacturers, cybersecurity and screening firms excluded, and each segment tagged.
What the filings show
The biggest security company in Britain doesn't look like one from the outside: Mitie Security is the security division of FM group Mitie, files its own accounts, and at £842M out-bills every standalone guard firm in the country. The famous name comes second — and only once you find the right entity. G4S's global filing shows £5.2B and four hundred thousand staff worldwide; its actual UK guarding business filed £506M.
This is a people business, and the staff column is the honest size measure: the firms here employ 105,444 people, most of them guards. Revenue per head in manned guarding runs at £30–50k — margins are wafer-thin and wages dominate — while the systems firms (ADT, Chubb, Verisure) earn multiples of that per employee. Same SIC code, very different economics.
Growth is broad: Lodge Security (+77%), Unitrust Protection (+30%), City Group Security (+27%), Anchor Group (+25%) lead the table, and barely a firm in the top 20 shrank — corporate Britain is buying more security, not less. The structural shift is consolidation: FM groups keep absorbing guarding firms (Bidvest Noonan, OCS and Atalian all swallowed ranked names in recent years), which is exactly why several familiar brands now appear in the "can't rank" list rather than the table.
Top 50 security companies in the UK by filed turnover
Latest accounts filed as of June 2026 · refreshed monthly
| # | Firm | Turnover | YoY | Staff | Accounts |
|---|---|---|---|---|---|
| 01 | Mitie Security Security services subsidiary Mitie Security Limited — the security division of FM group Mitie plc, which files it separately. It out-bills every standalone guarding firm in the UK. | £842M | +18% | 17,010 | FY to Mar 2025 |
| 02 | G4S (UK) Private security services provider G4S Secure Solutions (UK) Limited, the UK guarding business. The G4S Limited global group (£5.2B, Allied Universal’s international arm) is not ranked — see methodology. | £506M | +1% | 13,153 | FY to Dec 2024 |
| 03 | ADT systems Fire and security systems provider ADT Fire and Security plc. | £402M | +2% | 2,325 | FY to Sept 2025 |
| 04 | Wilson James Security and logistics services provider Security, aviation and logistics services; files under a construction SIC code. | £355M | +18% | 6,173 | FY to Jul 2025 |
| 05 | Securitas UK Private security services provider Securitas Security Services (UK) Limited; sibling Securitas Technology files separately. | £345M | +4% | 6,349 | FY to Dec 2025 |
| 06 | Chubb Fire & Security systems Fire and security systems provider Part of APi Group. | £292M | +22% | 1,941 | FY to Dec 2024 |
| 07 | Kingdom security & support services Security and facilities management provider Kingdom Services Group Limited, consolidated — security alongside cleaning and other soft services. | £211M | +11% | 11,437 | FY to Mar 2025 |
| 08 | ICTS UK aviation security Private security services provider | £194M | +14% | 4,717 | FY to Dec 2025 |
| 09 | CIS Security Private security holding company CIS Holdings Limited, consolidated. | £164M | +23% | 3,343 | FY to Jul 2025 |
| 10 | Argenbright Security Europe aviation security Private security services provider UK arm of the US Argenbright group. | £157M | — | 3,226 | FY to Dec 2024 |
| 11 | Carlisle Support Services security & support services Holding company for support services Carlisle Support Services Group Limited, consolidated. | £144M | +14% | 4,074 | FY to Dec 2024 |
| 12 | ASEL aviation security Private security services provider ASEL Integrated Security Solutions Ltd. | £133M | — | 2,721 | FY to Dec 2024 |
| 13 | Corps Security Private security services provider Corps of Commissionaires Management Limited — founded 1859, the world’s oldest security company. | £123M | +6% | 3,057 | FY to Mar 2025 |
| 14 | G4S Cash Solutions cash services Cash management and transit provider Files separately from the ranked G4S guarding entity. | £112M | +0% | 1,813 | FY to Dec 2024 |
| 15 | Securigroup Private security services provider Securigroup Limited, consolidated — Scotland’s largest independent. | £102M | +14% | 2,934 | FY to Sept 2025 |
| 16 | Vaultex cash services Joint venture cash management company The UK banks’ jointly-owned cash processor (HSBC/Barclays); files under a financial SIC. | £89M | -4% | 1,135 | FY to Oct 2025 |
| 17 | Verisure UK systems Monitored security systems provider UK arm of Europe’s largest monitored-alarm group. | £86M | +8% | 1,334 | FY to Dec 2024 |
| 18 | Orbis Protect Vacant property security provider Vacant property and lone-worker protection. | £84M | -9% | 725 | FY to Mar 2025 |
| 19 | Amulet Private security services provider Churchill Group’s security division. | £78M | +16% | 1,669 | FY to Jun 2025 |
| 20 | Loomis UK cash services Cash-in-transit security provider | £77M | +4% | 1,084 | FY to Dec 2024 |
| 21 | Ward Security Private security services provider Part of Bidvest Noonan; files separately under SIC 84240. | £75M | +19% | 1,476 | FY to Dec 2024 |
| 22 | Kings Secure Technologies systems Holding company for security systems Primekings Holding Limited, consolidated. | £69M | +20% | 798 | FY to Oct 2024 |
| 23 | Man Commercial Protection Private security services provider | £58M | -0% | 1,174 | FY to Sept 2025 |
| 24 | First Response security & support services Security and facilities management provider First Response Group — security and FM. | £58M | +5% | 937 | FY to Jul 2025 |
| 25 | Sunwin Services cash services Private security services subsidiary Cash-in-transit and retail security. | £51M | +0% | 475 | FY to Dec 2024 |
| 26 | Ambrey maritime security Private maritime security provider | £50M | -18% | 85 | FY to Jun 2024 |
| 27 | Secom systems Security and fire systems provider UK arm of Japan’s SECOM. | £49M | -8% | — | FY to Dec 2024 |
| 28 | Showsec event security Event and venue security specialist | £48M | +22% | 140 | FY to Dec 2025 |
| 29 | Lodge Security Private security services provider Retail security and loss prevention. | £46M | +77% | 1,357 | FY to Jul 2025 |
| 30 | Effective Security Private security services provider | £42M | — | 114 | FY to Feb 2025 |
| 31 | Triton security & FM Security and facilities management provider Triton Security & Facilities Management. | £40M | -0% | 223 | FY to Dec 2024 |
| 32 | STM Group Private security services provider | £40M | — | 1,085 | FY to Aug 2025 |
| 33 | City Group Security security & support services Security and facilities management provider | £35M | +27% | 538 | FY to Jun 2025 |
| 34 | Profile Security Security services provider OCS Group’s guarding subsidiary, which files separately. | £52M | — | 1,022 | 18-mo period to Mar 2025 |
| 35 | Reliance High-Tech systems Electronic security systems provider Independent security technology integrator. | £32M | +10% | 172 | FY to Mar 2025 |
| 36 | Pointer systems Security systems holding company Pointer Holdings Limited, consolidated. | £31M | +19% | 249 | FY to Jun 2025 |
| 37 | Synectics Systems systems Security systems service provider Operating company of listed surveillance group Synectics plc. | £28M | +10% | 128 | FY to Nov 2024 |
| 38 | Unitrust Protection Holdco for a security provider Unitrust Protection Services Holdings Limited, consolidated. | £27M | +30% | 501 | FY to Mar 2025 |
| 39 | Anchor Group security & support services Security and facilities management provider | £26M | +25% | 797 | FY to Oct 2024 |
| 40 | Constant Security Private security services provider | £25M | — | 881 | FY to Dec 2025 |
| 41 | Evolution systems Employee-owned security systems integrator Evolution (Electronic Security Systems) Ltd — integrated fire and security. | £23M | +13% | 148 | FY to Mar 2025 |
| 42 | Gough & Kelly Security systems and services group Gough & Kelly Group Limited, consolidated. | £22M | +19% | 268 | FY to Jul 2024 |
| 43 | Ocular Integration systems Security systems integrator | £21M | +17% | 96 | FY to Nov 2024 |
| 44 | Kings Guarding Solutions Private security services provider | £20M | +13% | 368 | FY to Oct 2024 |
| 45 | Spy Alarms systems Fire and security systems installer | £19M | +12% | 216 | FY to Jun 2025 |
| 46 | RMS Cash Solutions cash services Cash management and security services Northern Ireland cash-in-transit operator. | £19M | +21% | 204 | FY to Mar 2025 |
| 47 | GSL Dardan Specialist security services provider | £19M | +22% | 444 | FY to Mar 2025 |
| 48 | EA-RS systems Fire and security systems provider EA-RS Fire Engineering group entity — fire and security. | £19M | +25% | 138 | FY to Sept 2024 |
| 49 | Secur-It Private security services provider | £18M | +14% | 124 | FY to Sept 2024 |
| 50 | Mercury Security security & support services Security and facilities management provider Northern Ireland security and FM group. | £14M | -4% | 453 | FY to Dec 2024 |
The next 2
Firms ranked 51–52
| 51 | Britsafe | £14M | +6% | FY to Mar 2025 |
| 52 | Custom Security | £14M | +12% | FY to Mar 2025 |
The firms we can't rank
Security's missing names are mostly inside FM groups that don't separate the numbers.
- Bidvest Noonan — security and cleaning revenue are not separable in its UK filings (its Ward Security subsidiary files separately and is ranked)
- OCS — security sits inside an integrated FM group with no separate filing
- Mitie (group security total) — Mitie Security Ltd is ranked; the wider group’s security-adjacent revenue in other entities cannot be isolated
- Axis Security — acquired by Atalian Servest; no longer files separately
- Marlowe (fire & security compliance) — group restructured through divestments; successor filing entity to be confirmed
How this list is built
Source. The latest annual accounts each firm filed at Companies House. Where a firm files consolidated group accounts, the group figure is used; the entity ranked is named under each firm. Where a firm filed a transition period longer or shorter than twelve months (flagged in the Accounts column), the table shows the filed figure but the firm is ranked on its annualised equivalent.
Who counts as a security company. Manned guarding, security systems and monitoring, cash services, and aviation, maritime and event security — each tagged. We exclude equipment manufacturers and distributors (Hikvision, Assa Abloy), cybersecurity, employment screening, corporate investigations, and — because SIC codes are what they are — two regulators (the FCA and SRA both file under "investigation activities").
Scope. UK operating entities only. The G4S Limited global group and other multi-territory entities are excluded in favour of their UK filers; security divisions that file separately from FM parents (Mitie Security, Ward, Amulet, Profile) are ranked with their ownership noted, while groups whose security revenue can't be separated (Bidvest Noonan, OCS) are named in the "can't rank" section instead of being guessed at.
Cadence. Rebuilt monthly as new accounts land. Spot a security firm we've missed or misread? Tell us — the methodology only works if it's challenged.
Quick answers
- What is the biggest security company in the UK?
- Mitie Security — £842M in its latest filed accounts with 17,010 staff. It files separately from its FM parent Mitie plc, and it out-bills every standalone guarding firm in Britain.
- Isn't G4S the biggest security company?
- Globally, yes — G4S Limited files £5.2B with over 400,000 staff worldwide, but that entity is Allied Universal's international arm, not a UK business. Its actual UK guarding company, G4S Secure Solutions (UK), filed £506M and is ranked second.
- How many people work for the UK's top security companies?
- The firms on this list directly employ 105,444 people — guarding is one of the UK's largest people businesses, and the manned-guarding firms alone account for 63,840 of them.
- Why are there no cybersecurity companies on this list?
- Different industry, different list. This ranking covers physical security — guarding, systems, cash services, aviation and maritime security. Cybersecurity firms, CCTV manufacturers, employment-screening companies and corporate-investigation consultancies are excluded.