| 401 King Street Limited | Real estate | 2018 |
| 401 Sports Strategies Limited | Arts & recreation | 2025 |
| 401 URR Management Limited | Households | 2003 |
| 401VAULT Limited | Wholesale & retail | 2025 |
| 402 Camden Road Management Company Limited | Households | 1997 |
| 402 Seven Sisters Road Limited | Real estate | 2017 |
| 402 Southbury Ltd | Real estate | 2022 |
| 403 Digital Ltd | Information & communication | 2019 |
| 403 Harrow Road Ltd | Real estate | 1998 |
| 403 Industries Ltd | Information & communication | 2022 |
| 4036 HC Ltd | Health & social care | 2024 |
| 404 Business NOT Found Ltd | Extraterritorial | 2020 |
| 404 Capital Ltd | Real estate | 2025 |
| 404 Dino Consulting Ltd | Information & communication | 2024 |
| 404 Fitness Group Ltd | Arts & recreation | 2025 |
| 404 Found US Limited | Wholesale & retail | 2025 |
| 404 Games Ltd | Information & communication | 2023 |
| 404 Hosting Ltd | Extraterritorial | 2022 |
| 404 Innovations Limited | Information & communication | 2025 |
| 404 Marketing Solutions Ltd | Professional & scientific | 2024 |
| 404 Members Club Ltd | Arts & recreation | 2023 |
| 404 Operations Limited | Information & communication | 2025 |
| 404 Property Investment Limited | Households | 2019 |
| 404! Solutions Ltd | Information & communication | 2021 |
| 4040 Consulting Ltd | Professional & scientific | 2020 |
| 4040 Limited | Administrative & support | 2025 |
| 4040 Padel Group Limited | Arts & recreation | 2025 |
| 4047 Consulting Limited | Professional & scientific | 2023 |
| 404HOURS Ltd | Wholesale & retail | 2026 |
| 404MEMEBOT Ltd | Information & communication | 2025 |
| 406 Consultancy Company Limited | Real estate | 2025 |
| 407 Services Ltd | Wholesale & retail | 2025 |
| 407 Ventures Ltd | Information & communication | 2024 |
| 40BPM Ltd | Information & communication | 2019 |
| 40DOTS Ltd | Professional & scientific | 2015 |
| 40FI Limited | Information & communication | 2022 |
| 40FT Brewery Limited | Manufacturing | 2015 |
| 40GFL Properties Ltd | Real estate | 2025 |
| 40HHR Limited | Real estate | 2021 |
| 40K Designs Ltd | Professional & scientific | 2025 |
| 40L Properties Ltd | Real estate | 2025 |
| 40MEDIA Group Ltd | Information & communication | 2025 |
| 40P Ltd | Professional & scientific | 2025 |
| 40ROCK Ltd | Professional & scientific | 2025 |
| 40SCROMARTY Productions Ltd | Information & communication | 2022 |
| 40SIX Ltd | Wholesale & retail | 2023 |
| 41 & 41A Goldsborough Road Management Company Ltd | Professional & scientific | 2010 |
| 41 - 42 Sandall Close Limited | Extraterritorial | 2021 |
| 41 - 43 Brook Street LLP | | 2008 |
| 41 Aberdare Gardens NW6 Freehold Limited | Households | 2012 |
| 41 Addison Gardens Limited | Households | 2010 |
| 41 Adolphus Road Freehold Limited | Households | 2010 |
| 41 AG Limited | Households | 1971 |
| 41 Albemarle Limited | Financial services | 2025 |
| 41 Ambleside Avenue RTM Company Limited | Households | 2019 |
| 41 and 41A Midmoor Road Limited | Real estate | 2001 |
| 41 and 43 Charlmont Road (Freehold) Company Limited | Real estate | 2007 |
| 41 and 43 Moreton Street Freehold Limited | Households | 2004 |
| 41 ARV Management Company Limited | Households | 2018 |
| 41 Avondale Road RTM Company Limited | Households | 2025 |
| 41 Avonmore Road Freehold Limited | Households | 2014 |
| 41 Belsize Park Freehold Company Limited | Households | 2006 |
| 41 Berrymead Gardens Ltd | Extraterritorial | 2003 |
| 41 Birchington Road Management Company Limited | Households | 1997 |
| 41 Birdhurst Road Management Company Limited | Administrative & support | 2004 |
| 41 Bloemfontein Road Management Company Limited | Households | 2023 |
| 41 Bramham Gardens Management Company Limited | Households | 1975 |
| 41 Buckingham Palace Road Limited | Hospitality | 2000 |
| 41 Buckingham Road Management Company Limited | Real estate | 1983 |
| 41 Buckland Crescent (Management) Limited | Households | 1986 |
| 41 Burlington Road Chiswick London Limited | Households | 1991 |
| 41 Church Crescent Residents Limited | Households | 1984 |
| 41 Churchfield Avenue RTM Company Limited | Households | 2026 |
| 41 Colville Terrace Limited | Households | 2012 |
| 41 Commercial Street Ltd | Hospitality | 2017 |
| 41 Consort House Ltd | Real estate | 2022 |
| 41 Cranwich Road Limited | Households | 1998 |
| 41 Croxley Road Limited | Extraterritorial | 2008 |
| 41 Danbury Street Limited | Real estate | 2000 |
| 41 Darnley Road Management Company Limited | Households | 1994 |
| 41 Dartmouth Road Limited | Households | 2018 |
| 41 Dawes Road Limited | Real estate | 2017 |
| 41 Devonia Road Freehold Limited | Households | 2017 |
| 41 Devonport Road Limited | Professional & scientific | 2008 |
| 41 Eastfields Road Ltd | Real estate | 2021 |
| 41 Eaton Mews North Ltd | Professional & scientific | 2014 |
| 41 Edison Grove RTM Company Limited | Households | 2025 |
| 41 Elvaston Place Limited | Households | 1998 |
| 41 Epsom Road Management Limited | Real estate | 2020 |
| 41 Estates Limited | Real estate | 2025 |
| 41 Fairfield Ltd | Real estate | 2022 |
| 41 Ferncroft Avenue NW3 Limited | Households | 1988 |
| 41 Filmer Road LLP | | 2015 |
| 41 Florence Road Limited | Households | 2020 |
| 41 Gateley Road RTM Company Limited | Real estate | 2011 |
| 41 Gayton Road Limited | Households | 2007 |
| 41 Georges Ltd | Real estate | 2026 |
| 41 Gerrard Road Limited | Households | 2012 |
| 41 Glenarm Road Limited | Households | 2016 |
| 41 Glenmore Road Management Company Limited | Households | 2013 |