| 12 Teignmouth Road RTM Company Limited | Households | 2026 |
| 12 the Avenue Management Limited | Real estate | 1994 |
| 12 the Drive Ltd | Real estate | 2017 |
| 12 Things Ltd | Wholesale & retail | 2026 |
| 12 TLB Limited | Construction | 2025 |
| 12 to 15 Saville Place (Clifton) Limited | Households | 2020 |
| 12 Touch Productions Ltd | Professional & scientific | 2025 |
| 12 Tournay Road Freehold Limited | Households | 2020 |
| 12 Trinity Street Management Limited | Real estate | 2014 |
| 12 Tysoe Management Limited | Households | 2007 |
| 12 Ullswater Road Limited | Households | 2003 |
| 12 Ulverscroft Road Ltd | Households | 2025 |
| 12 Ventures Ltd | Extraterritorial | 2012 |
| 12 Verbena Gardens W6 9TP Limited | Households | 2006 |
| 12 Versailles Road Limited | Real estate | 2003 |
| 12 Victoriaterrace Limited | Real estate | 2018 |
| 12 Vineyard Ltd | Real estate | 2025 |
| 12 Wandsworth Common Northside Management Company Limited | Households | 2009 |
| 12 Warrington Crescent Freehold Limited | Households | 2018 |
| 12 Well Walk (Management) Limited | Real estate | 1997 |
| 12 Wells Mews Limited | Real estate | 2022 |
| 12 Weltje Road Limited | Other services | 2014 |
| 12 Westbourne Terrace Road Limited | Households | 2026 |
| 12 Westview Ltd | Real estate | 2022 |
| 12 Whittingstall Road RTM Company Limited | Households | 2023 |
| 12 Whorlton Road Limited | Households | 2020 |
| 12 Witherington Road (Management Company) Limited | Real estate | 2015 |
| 12 Woodside Limited | Real estate | 2021 |
| 12 Woolstone Road Management Company Limited | Households | 2005 |
| 12 Worton Court Limited | Real estate | 2026 |
| 12 Yard Productions (Investments) Limited | Information & communication | 2001 |
| 12 York Grove SE15 RTM Company Limited | Administrative & support | 2004 |
| 12-12A Maple Road Ltd | Households | 2024 |
| 12-13 Market Place (Freehold) Limited | Real estate | 2023 |
| 12-13 Richmond Buildings RTM Company Limited | Households | 2019 |
| 12-14 Brudenell Road Management Company Limited | Professional & scientific | 2002 |
| 12-14 Clifton Gardens (Management) Limited | Households | 1987 |
| 12-14 Egerton Place Freehold Limited | Households | 2007 |
| 12-14 Folgate Limited | Professional & scientific | 1998 |
| 12-14 Warrior Square RTM Company Limited | Households | 2025 |
| 12-16 Ainsley Street Limited | Households | 2023 |
| 12-16 HS Walton Limited | Administrative & support | 2017 |
| 12-18 High Road Management Company Limited | Households | 2022 |
| 12-18 Highbridge Wharf Greenwich Limited | Households | 2007 |
| 12-18 Hill Street Investments Limited | Real estate | 2002 |
| 12-19 Cheyne Gardens London Limited | Households | 2010 |
| 12-20 Rosina Street Limited | Real estate | 2016 |
| 12-22 Finchley Road Advisory Limited | Real estate | 2015 |
| 12-22 Finchley Road Developments Limited | Construction | 2015 |
| 12-26 Spurgeon Road Freehold Limited | Households | 2012 |
| 12-30 Ltd | Professional & scientific | 2022 |
| 12.23 Ltd | Wholesale & retail | 2021 |
| 12/12 Healthcare Ltd | Education | 2017 |
| 12/13 Mecklenburgh Square RTM Company Limited | Households | 2016 |
| 12/14 Surrey Road RTM Company Limited | Households | 2005 |
| 12/14 Willow Road Limited | Real estate | 2009 |
| 12/15 Rheidol Terrace (Management) Limited | Real estate | 1983 |
| 12/16 Darwin Road Residents Association Limited | Real estate | 1976 |
| 12/20 ST Mary's Grove Limited | Households | 2002 |
| 120 & 120A Claxton Grove (Freehold) Ltd. | Households | 2013 |
| 120 Amhurst Road Limited | Households | 2001 |
| 120 Archway Road Limited | Construction | 2023 |
| 120 Barons Court Road Freehold Limited | Households | 2026 |
| 120 Bravington Road Limited | Professional & scientific | 1999 |
| 120 Brondesbury Park Limited | Real estate | 2008 |
| 120 Bulwer Road Management Limited | Real estate | 2002 |
| 120 Cavendish Road Management Company Limited | Real estate | 2009 |
| 120 Cheltenham Road Freehold Limited | Extraterritorial | 2018 |
| 120 Clapham Common Management Company Limited | Real estate | 2000 |
| 120 Crest Estates Limited | Real estate | 2016 |
| 120 Dalberg Road Management Limited | Households | 2015 |
| 120 Drakefell Road (London) Limited | Hospitality | 2012 |
| 120 Edith Road Limited | Households | 2003 |
| 120 Farringdon Road Ltd | Real estate | 2020 |
| 120 Ferme Park Road Freehold Company Limited | Households | 2016 |
| 120 Finborough Road Limited | Real estate | 2016 |
| 120 Fire Ltd | Construction | 2023 |
| 120 Goodrich Road Limited | Administrative & support | 2000 |
| 120 KRC Investments (NO. 2) Limited | Real estate | 2002 |
| 120 KRC Investments Nominee Limited | Real estate | 2002 |
| 120 Marlborough Limited | Real estate | 2010 |
| 120 Middleton Road Limited | Households | 2005 |
| 120 Mill Lane Limited | Real estate | 2022 |
| 120 Moorgate Tenant Limited | Real estate | 2017 |
| 120 Nightingale Lane Limited | Households | 2013 |
| 120 Olinda Ltd | Real estate | 2017 |
| 120 Preston Road Limited | Real estate | 2019 |
| 120 Springbank Road Limited | Households | 2016 |
| 120 ST Julians Farm Road RTM Company Ltd | Households | 2010 |
| 120 Whitechapel Road Management Limited | Real estate | 2025 |
| 120 Wimbledon Hill Road Management Company Limited | Households | 2005 |
| 120-122 Morning Lane Limited | Real estate | 2015 |
| 1200 Plus Limited | Health & social care | 2013 |
| 1202 Ltd | Professional & scientific | 2023 |
| 1204 Design Ltd | Professional & scientific | 2025 |
| 1206 Ltd | Wholesale & retail | 2025 |
| 1206 Partners Ltd | Professional & scientific | 2021 |
| 1207 Limited | Professional & scientific | 2022 |
| 1208 Properties Ltd | Real estate | 2024 |
| 120B Acton Lane Limited | Construction | 2014 |