The largest security systems service activities companies in London

Ranked by shareholders' funds, from 57 active companies in the EC postcode area.

"Largest" here means shareholders' funds — what the most recent balance sheet says the company is worth. It is the only measure of size filed by enough companies to rank on.

Companies that have never filed accounts cannot appear, however big they are. Figures are as filed at Companies House and can be a year or more old.

Security systems service activities in London top 20

1. QCIC LTD

£1,286,968 06318342 since 2007
2. AD HOC UK SECURITY LTD

£952,781 10516844 since 2016
3. FORCEFIELD LIMITED

£944,900 11617850 since 2018
4. KEY PATROL LIMITED

£823,758 07979198 since 2012
5. OPEM LIMITED

£803,533 06466990 since 2008
6. INVUE SECURITY PRODUCTS UK LIMITED

£635,401 09404589 since 2015
7. SYNERGY SECURITY LIMITED

£354,384 08446730 since 2013
8. ABSOLUTE SOFTWARE EMEA LIMITED

£272,776 05802063 since 2006
9. JAY SECURITY MANAGEMENT LTD

£99,327 07515354 since 2011
10. PRO 1 GROUP LTD

£85,918 11964197 since 2019
11. BIG BROTHER ALL SECURITY LTD

£80,100 09395527 since 2015
12. SUPERB SECURITY SOLUTIONS LTD

£78,979 11225699 since 2018
13. PARAGON SECURITY SOLUTIONS LTD

£50,553 13387330 since 2021
14. SENSS ELECTRICAL AND SECURITY SERVICES LTD

£49,037 08529825 since 2013
15. S&S FIRE & SECURITY LTD

£44,794 13523787 since 2021
16. SGW SAFETY & SECURITY LIMITED

£35,659 07650324 since 2011
17. 2BSECURE LTD

£32,953 14805764 since 2023
18. BLITZ PC AND SECURITY SOLUTIONS LTD

£31,910 09140371 since 2014
19. PM HOMELAND SECURITY LIMITED

£28,622 07418267 since 2010
20. JPH SECURITY LTD

£26,143 14535490 since 2022