| 312 Utilities Limited | Bootle | 2021 |
| 313 Construction Ltd | Leicester | 2025 |
| 313 Design and Build Ltd | London | 2023 |
| 313 Developments Ltd | Wakefield | 2025 |
| 313 Electrics Ltd | Exmouth | 2025 |
| 313 Interiors Ltd | London | 2026 |
| 313 Roofing Ltd | Bordon | 2023 |
| 313 Surveyors Ltd | London | 2026 |
| 313AT Construction Ltd | Manchester | 2025 |
| 316 Building Services Limited | Huntingdon | 2013 |
| 317 Finchley Road Construction Co Limited | Southgate | 2019 |
| 317 Finchley Road Ltd | Southgate | 2014 |
| 31GOLFGREENS Ltd | Abingdon | 2025 |
| 32 Cherry Tree Lane Ltd | Portsmouth | 2025 |
| 32 Garages Ltd | Hitchin | 2026 |
| 32 High Street, Limited | Chelmsford | 2016 |
| 32 Lord Street Gainsborough Ltd | Gainsborough | 2025 |
| 32 One Homes Cheveley Limited | Ely | 2021 |
| 32 One Homes Limited | London | 2020 |
| 32 Property Upkeep Ltd | London | 2025 |
| 32 Sparks Ltd | Glasgow | 2022 |
| 32-33 White Rock Limited | Hastings | 2017 |
| 32/34 Eagle Wharf Road Limited | London | 2014 |
| 321 Developments Ltd | Fleet | 2019 |
| 321 Estates Construction Limited | Mansfield | 2023 |
| 3242 Investments Ltd | Wallington | 2015 |
| 325 Lordship Road Limited | London | 2020 |
| 328 ST James Road Limited | London | 2020 |
| 32A Laurel Road Limited | St. Helens | 2018 |
| 33 Beresford Avenue Limited | London | 2024 |
| 33 Construction Services Ltd | London | 2020 |
| 33 Degree Construction Ltd | Liverpool | 2026 |
| 33 Electrics Ltd | Morden | 2021 |
| 33 JWR Ltd | Bristol | 2025 |
| 33 Marsh Lane Residents Association Limited | Stanmore | 1987 |
| 33 Newling Street Ltd | London | 2024 |
| 33 South Street Ltd | Hove | 2017 |
| 330 ST James Road Limited | London | 2020 |
| 333 CN Construction Ltd | Winchmore Hill | 2009 |
| 333 Homes Limited | Wells | 2012 |
| 333 Housing Ltd | London | 2023 |
| 334 Ramsbury Oxford Limited | London | 2004 |
| 337 Contracts Limited | Johnstone | 2023 |
| 338 Euston Road Limited | London | 1994 |
| 338 Precision Properties Ltd | Manchester | 2021 |
| 33CS Limited | London | 2022 |
| 33MDR Ltd | Milton Keynes | 2015 |
| 33N Group Ltd | Portsmouth | 2025 |
| 33PLUS Limited | Chorley Old Road | 2023 |
| 33SZ Holdings Ltd | London | 2026 |
| 34 Belsize Lane Ltd | London | 2023 |
| 34 Mulgrave Ltd | London | 2023 |
| 34 Norfolk Road Ltd | Waterlooville | 2018 |
| 34 QG Limited | London | 2023 |
| 34 Red House Ltd | St Albans | 2021 |
| 34 Westovercliff 2 Ltd | Westbourne | 2025 |
| 34 Westovercliff Limited | Poole | 2023 |
| 34 WPA Ltd | Maidenhead | 2019 |
| 34-36 Canal Road Ltd | Leeds | 2016 |
| 341 Solutions Limited | London | 2025 |
| 345 Brickwork Limited | Blackpool | 2020 |
| 345 Building Ltd | Altrincham | 2024 |
| 345 Care Ltd | Woking | 2025 |
| 345 Civil Engineering Ltd | Leeds | 2026 |
| 345 Construction Ltd | Bracknell | 2021 |
| 345 Construction Services Limited | Cannock | 2022 |
| 345 Design & Build Ltd | Derby | 2020 |
| 345 Flooring Solutions Ltd | Solihull | 2018 |
| 345 Groundworks Limited | Farnham | 2017 |
| 345 Interior Projects Ltd | Linwood | 2024 |
| 345 Interiors Ltd | Woking | 2007 |
| 345 Setting OUT and Surveys Limited | Deal | 2020 |
| 345 Training Ltd | Huntingdon | 2025 |
| 349 Building & Maintenance Limited | High Wycombe | 2017 |
| 34BUS CIC | Brighton | 2022 |
| 35 - 39 Station Road Ltd | Potters Bar | 2015 |
| 35 Albert RD Development Ltd | Newcastle Upon Tyne | 2023 |
| 35 Shore Road Limited | Buckhurst Hill | 2017 |
| 35 ST Mary's Road Limited | Harrow | 2020 |
| 35 Woodhill Crescent Limited | Hounslow | 2024 |
| 350 Euston Road Limited | London | 1993 |
| 350 KS DEV Ltd | Stanmore | 2024 |
| 350 KS Development Ltd | Stanmore | 2024 |
| 350 KS SPV Limited | Stanmore | 2024 |
| 353 355 Alexandra Road Ltd | London | 2026 |
| 354 Development Ltd | Mildenhall | 2026 |
| 3554 Amun Ltd | Portsmouth | 2023 |
| 358 Finchley Road Limited | Watford | 2003 |
| 36 Flitwick Road Ltd | Shefford | 2025 |
| 36 HS Limited | London | 2025 |
| 36 Projects Limited | South Ockendon | 2018 |
| 36-44 Lodge Road Limited | Leigh On Sea | 2005 |
| 360 a E I Services Ltd | Newcastle Upon Tyne | 2019 |
| 360 Air-Conditioning Ltd | Fareham | 2021 |
| 360 Build (Ashford) Ltd | Ashford | 2019 |
| 360 Build Group Ltd | Redhill | 2026 |
| 360 Builders Limited | Reading | 2018 |
| 360 Buildings Limited | Tameside | 2016 |
| 360 Business Solutions Ltd | Glasgow | 2025 |
| 360 Cable Installation Services Ltd | London | 2021 |