| 3KS Consultancy Ltd | Professional & scientific | 2021 |
| 3S Home Cleaning Services Ltd | Administrative & support | 2024 |
| 3SECOND Ltd | Professional & scientific | 2025 |
| 3SGUK Limited | Construction | 2015 |
| 3SHTECH Ltd | Information & communication | 2022 |
| 3T Investments Ltd | Real estate | 2026 |
| 3VS UK Limited | Professional & scientific | 2004 |
| 3W Health Limited | Health & social care | 2025 |
| 4 Aces Properties Ltd | Real estate | 2023 |
| 4 Effingham Street Limited | Households | 2014 |
| 4 Mark Construction (London) Limited | Construction | 2005 |
| 4 Mark Construction Limited | Construction | 2025 |
| 4 Paws in the Park Limited | Other services | 2025 |
| 4 Pembroke Road (Wembley) Management Ltd | Real estate | 2021 |
| 4 Star DRY Cleaners Ltd | Other services | 2018 |
| 4/4A Old ST Andrews Mansions Limited | Real estate | 2020 |
| 40 Eastcote Road Property Company Limited | Households | 2005 |
| 40 Portland Road Ltd | Real estate | 2020 |
| 40809 Limited | Hospitality | 2018 |
| 41 Ruskin Road RTM Company Limited | Households | 2014 |
| 418 (Uxbridge Road) Ltd | Real estate | 2006 |
| 42 (Bideford Avenue) Ltd | Real estate | 2006 |
| 42 Keats Ltd | Real estate | 2023 |
| 42 Welldon Crescent Resident's Association Limited | Households | 1991 |
| 42-43 Sekforde Street Management Company Limited | Real estate | 2004 |
| 429 New Cross Road RTM Company Ltd | Households | 2022 |
| 43 Grosvenor Crescent (Kingsbury) Management Limited | Real estate | 2013 |
| 43 Upper Richmond Road (Freehold) Limited | Administrative & support | 2013 |
| 43DTV Properties Limited | Households | 2025 |
| 44 Fairview Crescent (Harrow) Limited | Households | 2010 |
| 44 Gayton Road RTM Company Limited | Real estate | 2014 |
| 448-450 Allenby Road Greenford Limited | Professional & scientific | 2015 |
| 45 ST Stephens Avenue Limited | Households | 1997 |
| 459 Rayners Lane Ltd | Construction | 2024 |
| 46 Fordingley Road Freehold Limited | Households | 2017 |
| 46 Lowlands Road (Freehold) Limited | Households | 2019 |
| 46 Nibthwaite Limited | Households | 2020 |
| 46-49 Milman Close Freehold Limited | Households | 2011 |
| 47 Cumberland Street Ltd | Real estate | 2021 |
| 470NM Limited | Health & social care | 2022 |
| 48 Cunningham Park (Harrow) Ltd | Real estate | 2011 |
| 48 Spencer Road Harrow Freehold Limited | Households | 2018 |
| 48 the Mall Limited | Construction | 2014 |
| 48CONSULTING Limited | Professional & scientific | 2018 |
| 49 Headstone Road Management Ltd | Administrative & support | 2015 |
| 49 Roxborough Park Management Limited | Real estate | 1999 |
| 49-53A Pinner Road Harrow RTE Company Limited | Households | 2007 |
| 4A Commercial Management Consultants Limited | Construction | 2019 |
| 4BANGER Ltd | Wholesale & retail | 2025 |
| 4CARDS Limited | Manufacturing | 2023 |
| 4CCP Holding Ltd. | Administrative & support | 2003 |
| 4D Homes London Limited | Real estate | 2024 |
| 4D London Clinic Ltd | Other services | 2018 |
| 4DBALANCE Consultancy Ltd | Public administration | 2023 |
| 4DBALANCE Investments Ltd | Real estate | 2022 |
| 4DIODA Ltd | Professional & scientific | 2020 |
| 4ENSICMED Ltd | Health & social care | 2011 |
| 4EYES Optical Ltd | Health & social care | 2018 |
| 4FB Ltd | Wholesale & retail | 2024 |
| 4G Project Services Limited | Professional & scientific | 2021 |
| 4IAPPS Solutions Ltd | Information & communication | 2021 |
| 4K Barber Ltd | Other services | 2022 |
| 4K Soft Ltd | Information & communication | 2026 |
| 4M Barber Ltd | Other services | 2025 |
| 4M Developments Ltd. | Real estate | 2018 |
| 4PF Capital Limited | Financial services | 2022 |
| 4PMO Ltd | Information & communication | 2013 |
| 4U Bedroom and Kitchens Ltd | Manufacturing | 2026 |
| 4YOURLIFE Ltd | Extraterritorial | 2013 |
| 5 Belsize Square Limited | Professional & scientific | 1989 |
| 5 Mafhhis Limited | Hospitality | 2023 |
| 5 Star Apartments Limited | Administrative & support | 2008 |
| 5 Stars Plumbing and Heating Services Limited | Construction | 2024 |
| 5 Welldon Crescent RTM Company Limited | Real estate | 2008 |
| 5-8 Palm Court RTM Company Ltd | Households | 2022 |
| 50 Queens Gate Limited | Households | 2010 |
| 502 Jerome House Limited | Real estate | 2025 |
| 52 Queen's Gate Limited | Households | 2010 |
| 52762 Limited | Hospitality | 2023 |
| 53 Belsize Park Limited | Households | 1996 |
| 53/53A Pinner View Freehold Company Limited | Households | 2021 |
| 55 Churchfield Limited | Real estate | 2025 |
| 55 Parkgate Road Freehold Limited | Other services | 2003 |
| 55 Tanner Street RTM Company Limited | Households | 2019 |
| 56 Green Limited | Real estate | 2016 |
| 56 Properties Limited | Real estate | 2022 |
| 56 the Chase (NO 2) Ltd | Real estate | 2006 |
| 56ABN Ltd | Real estate | 2022 |
| 57 Eaton Square Limited | Real estate | 2014 |
| 58 West Heath Drive Management Limited | Real estate | 2013 |
| 58-60 Nibthwaite Road Management Limited | Administrative & support | 2010 |
| 58308 Limited | Hospitality | 2018 |
| 59 Charlotte Street Limited | Administrative & support | 2013 |
| 59 Cunningham Park Road Management Ltd | Households | 2019 |
| 5911 Limited | Real estate | 2022 |
| 5INQ Limited | Health & social care | 2024 |
| 5M Group Limited | Real estate | 2016 |
| 5R1 Limited | Financial services | 2007 |
| 5S Projects Limited | Professional & scientific | 2019 |
| 5STAR Roofcare Limited | Construction | 2019 |