# The biggest construction companies in South East

The construction companies registered in South East with the highest turnover in their latest filed accounts, ranked, with profit and growth.

Keltbray Built Environment is the biggest company among the construction companies registered in South East by turnover, with £320m in its latest filed accounts. RGCM and Atlas FM follow. Together the 10 companies below turned over £1.86bn in their latest filed years.

| Rank | Company | Town | Turnover | Year |
| ---: | --- | --- | ---: | --- |
| 1 | [Keltbray Built Environment](https://firmfacts.co/company/keltbray-built-environment-12548732) | Thames Ditton | £320m | FY to Oct 2025 |
| 2 | [RGCM](https://firmfacts.co/company/rgcm-02477053) | West Malling | £289m | FY to Dec 2025 |
| 3 | [Atlas FM](https://firmfacts.co/company/atlas-fm-02633080) | Datchet | £191m | FY to Dec 2025 |
| 4 | [Atlas FM Payroll](https://firmfacts.co/company/atlas-fm-payroll-15181418) | Slough | £183m | FY to Dec 2025 |
| 5 | [Riddingtons Cis & Payroll Solutions UK](https://firmfacts.co/company/riddingtons-cis-payroll-solutions-uk-10179530) | Swanley Village | £170m | FY to May 2024 |
| 6 | [Seko Logistics (London)](https://firmfacts.co/company/seko-logistics-london-04590887) | Windsor | £150m | FY to Dec 2022 |
| 7 | [Atlas Cleaning](https://firmfacts.co/company/atlas-cleaning-15181660) | Slough | £148m | FY to Dec 2024 |
| 8 | [Kellogg Brown & Root (U.K.)](https://firmfacts.co/company/kellogg-brown-root-uk-02021947) | Leatherhead | £147m | FY to Dec 2025 |
| 9 | [Knights Brown Construction](https://firmfacts.co/company/knights-brown-construction-02081940) | Hampshire | £136m | FY to Mar 2026 |
| 10 | [Sexton Holdings](https://firmfacts.co/company/sexton-holdings-04477211) | Littlehampton | £128m | FY to Dec 2025 |

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Updated 2026-11-02 from the latest filed accounts at Companies House (Open Government Licence v3.0). Page: https://firmfacts.co/blog/biggest-construction-companies-in-south-east