| 3M Property Holding Group Ltd | Birmingham | 2020 |
| 3M Property Management Limited | London | 2021 |
| 3M Ventures Limited | Beckenham | 2017 |
| 3M(UK) Ltd | Huddersfield | 2025 |
| 3MA Investments Limited | Gerrards Cross | 2016 |
| 3MC Edinburgh Limited | Edinburgh | 2025 |
| 3MCC Ltd. | Glasgow | 2005 |
| 3MD Ltd | Swanley Village | 2019 |
| 3ME Properties Ltd | Newcastle Upon Tyne | 2016 |
| 3ME Residential Properties Ltd | Newcastle Upon Tyne | 2022 |
| 3MG Business Consulting Ltd | Waterlooville | 2025 |
| 3MJ Kemp Ltd | Enfield | 2021 |
| 3MK Ltd | Birmingham | 2014 |
| 3MK Properties Limited | Farnham | 2021 |
| 3ML Properties Limited | London | 2022 |
| 3MOD Properties Limited | Heston | 2015 |
| 3MP Ltd | Wolverhampton | 2016 |
| 3MRG Limited | Bedford | 2016 |
| 3MS Investments Ltd. | London | 2026 |
| 3MS Properties Limited | Coventry | 2025 |
| 3MS Property Limited | Aldermaston | 2011 |
| 3MT Property Solutions Ltd | Kington | 2025 |
| 3MTLETTINGS Ltd | Llandysul | 2025 |
| 3MV Asset Advisors Limited | Redbridge | 2018 |
| 3MZ Homes Ltd | Telford | 2024 |
| 3MZ Properties Ltd | London | 2022 |
| 3N Acquisitions Ltd | London | 2017 |
| 3N Investments Ltd | London | 2016 |
| 3N Properties Limited | Morecambe | 2018 |
| 3N Property Group Ltd | Bradford | 2026 |
| 3N Property Limited | Renfrew | 2017 |
| 3N3 Properties Ltd | London | 2023 |
| 3NA Properties Ltd | Caerdydd | 2024 |
| 3NA Solutions Ltd | Hamilton | 2021 |
| 3NB North East Ltd | Sunderland | 2019 |
| 3NEWLYN Limited | London | 2020 |
| 3NITY Properties Ltd | Swanscombe | 2024 |
| 3NMS Property Ltd | Newport | 2021 |
| 3NOVA Ltd | Barnet | 2016 |
| 3NR Ltd | Altrincham | 2014 |
| 3NS Wealth Ltd | Maidstone | 2026 |
| 3OKTEM Ltd. | London | 2025 |
| 3P Housing Ltd | Birmingham | 2026 |
| 3P Inc Limited | Buntingford | 2022 |
| 3P Investments Limited | Leicester | 2021 |
| 3P Projects Ltd | London | 2025 |
| 3P Properties Limited | Peterborough | 2002 |
| 3P Property Ltd | Linwood | 2024 |
| 3P Ventures Limited | Watford | 2019 |
| 3PAREZ Limited | Carterton | 2025 |
| 3PB Investments Ltd | Walsall | 2021 |
| 3PBD Ltd | Eltham | 2013 |
| 3PL Real Estate Limited | Chalgrove | 2016 |
| 3PLE OSA Property Group Ltd | Northampton | 2025 |
| 3PLRE Limited | Bicester | 2016 |
| 3PMO Ltd | Rickmansworth | 2009 |
| 3PROPERTY Ltd | London | 2018 |
| 3P’S Property Management Ltd | Rugby | 2024 |
| 3R Ainsley Street Limited | Newcastle Upon Tyne | 2015 |
| 3R Buildings Limited | Birmingham | 2020 |
| 3R Estates Limited | Maidstone | 2017 |
| 3R Investments Ltd | London | 2017 |
| 3R Land & Property Ltd | Newcastle Upon Tyne | 1973 |
| 3R Property Group Ltd | Colne | 2026 |
| 3R Property Limited | Sutton Coldfield | 2020 |
| 3R Silver Street Limited | Newcastle Upon Tyne | 2015 |
| 3R Venture Limited | Kingston Upon Thames | 2021 |
| 3RD AGE Property Company Limited | London | 2025 |
| 3RD Avenue Developments Ltd. | East Sussex | 2003 |
| 3RD Echelon Ltd | Doncaster | 2020 |
| 3RD Floor Properties Limited | Wimbledon | 2006 |
| 3RD Generation Properties (Inverness) Limited | Dundee | 2023 |
| 3RD Generations Ltd | London | 2020 |
| 3RD Greenacres Management Company Limited | Letchworth Garden City | 1997 |
| 3RD Sector Assist Limited | Wilmslow | 2015 |
| 3RD Sector Estates Limited | Wythenshawe | 2022 |
| 3RD Sector Properties Limited | Chatham | 2009 |
| 3RD Sector Services Limited | Wythenshawe | 2019 |
| 3RE (11BST) Limited | London | 2025 |
| 3RE (33SJS) Limited | London | 2026 |
| 3RE London Property Limited | London | 2024 |
| 3RE UK (Dama 2) Limited | London | 2025 |
| 3REPUBLIC Ltd | Nuneaton | 2024 |
| 3RKC Ltd | London | 2023 |
| 3RL Ltd | Southampton | 2017 |
| 3RM Properties Limited | Leicester | 2015 |
| 3RPM Limited | Stourbridge | 2008 |
| 3RS Developments Limited | Tenbury Wells | 2024 |
| 3RS Holdings Limited | London | 2026 |
| 3RS Properties Limited | London | 2019 |
| 3RSP Limited | London | 2020 |
| 3RSP Realty Limited | London | 2024 |
| 3S Capital Limited | Wilmslow | 2012 |
| 3S Global Property Ltd | Derby | 2019 |
| 3S London Limited | London | 2015 |
| 3S Makan Limited | Manchester | 2024 |
| 3S Management Limited | Croydon | 2025 |
| 3S Properties Ltd | Nantwich | 2016 |
| 3S Property Group Limited | Guildford | 2026 |
| 3S T Investments Ltd | London | 2016 |