| 1 Software Limited | Information & communication | 2026 |
| 1 Sound Entertainment Limited | Arts & recreation | 2013 |
| 1 Southcote Road Management Company Limited | Administrative & support | 2016 |
| 1 Southside Limited | Households | 2005 |
| 1 Springall Street RTM Company Ltd | Households | 2013 |
| 1 SRY Limited | Construction | 2025 |
| 1 ST Choice HGV Training Ltd | Transport & logistics | 2014 |
| 1 ST Georges Avenue (Freehold) Ltd | Households | 2014 |
| 1 ST Katharine's Way Tenant Limited | Real estate | 2015 |
| 1 ST Mary's Terrace Limited | Construction | 2022 |
| 1 ST Marys Freehold Limited | Households | 2024 |
| 1 ST Peter's Square Tenant Limited | Real estate | 2017 |
| 1 ST. Cloud Road Freehold Limited | Households | 2016 |
| 1 ST. Stephen's Crescent Management Limited | Households | 1999 |
| 1 ST. Stephens Avenue Management Limited | Households | 1998 |
| 1 Stanger Road RTM Company Limited | Households | 2025 |
| 1 Stansfield Road SW9 9RY Ltd | Households | 2013 |
| 1 Stanton Road Limited | Households | 2010 |
| 1 Station Square Ltd | Real estate | 2020 |
| 1 Step London Ltd | Real estate | 2023 |
| 1 Stepup Limited | Health & social care | 2025 |
| 1 Sterndale Road (Residents Association) Limited | Households | 1989 |
| 1 Stonor Road West Kensington Limited | Real estate | 2012 |
| 1 Stop 4 Tyres Limited | Manufacturing | 2016 |
| 1 Stop Cars Ltd | Wholesale & retail | 2019 |
| 1 Stop Edits Ltd | Information & communication | 2025 |
| 1 Stop Money Ltd | Information & communication | 2019 |
| 1 Stop MOT Training Centre Ltd | Education | 2020 |
| 1 Stop Pilates Ltd | Arts & recreation | 2026 |
| 1 Stop Wash Limited | Other services | 2020 |
| 1 Streatley Road Limited | Households | 2022 |
| 1 Style Production & Events Limited | Information & communication | 2024 |
| 1 Take Entertainment Limited | Professional & scientific | 2025 |
| 1 Take Systems Limited | Information & communication | 2012 |
| 1 the Downs (Wimbledon) Residents Association Limited | Households | 1972 |
| 1 the Park (Highgate) Limited | Households | 1997 |
| 1 Theobald's Court Partnerco Limited | Real estate | 2009 |
| 1 THESSAL4:11 Holdings Ltd | Financial services | 2026 |
| 1 Thirlmere Road Limited | Households | 2012 |
| 1 Thornlaw Road Management Company Ltd | Hospitality | 2008 |
| 1 Tierney Road Management Company Limited | Households | 2011 |
| 1 to 1 Learning Academy Limited | Education | 2026 |
| 1 to 10 Clayton Court Ltd | Real estate | 2010 |
| 1 to 100 Ltd | Professional & scientific | 2024 |
| 1 to 17A Wellington Road (Residents Association) Limited | Households | 1999 |
| 1 to 3 Coffee Ltd | Wholesale & retail | 2016 |
| 1 to 360 Limited | Education | 2026 |
| 1 to 5 Bedford Villas Ltd | Real estate | 2013 |
| 1 Tonsley Road Management Limited | Real estate | 2011 |
| 1 Touch Medical Limited | Manufacturing | 2023 |
| 1 TR Limited | Real estate | 2021 |
| 1 Training International Ltd | Education | 2016 |
| 1 Tremlett Grove Freehold Company Ltd | Households | 2022 |
| 1 Trendy-Tech Ltd | Wholesale & retail | 2025 |
| 1 Tribe Organics Ltd | Wholesale & retail | 2023 |
| 1 Trilliard Publishing Ltd | Information & communication | 2024 |
| 1 Tulse Hill Limited | Households | 2017 |
| 1 Turville Street Management Company Limited | Households | 2013 |
| 1 Two 1 Direct Ltd | Professional & scientific | 2006 |
| 1 UP Management Company Limited | Real estate | 2007 |
| 1 UP Productions Ltd | Information & communication | 2022 |
| 1 Upper Grove RTM Company Limited | Households | 2018 |
| 1 Vale ROW Freehold Limited | Households | 2024 |
| 1 Vardens Road Limited | Households | 2007 |
| 1 Verif Ltd | Administrative & support | 2025 |
| 1 Vermont Road (Freehold) Limited | Households | 2006 |
| 1 Vernon Yard Limited | Construction | 2003 |
| 1 Vicarage Mansions Freehold Ltd | Households | 2018 |
| 1 Villas Limited | Administrative & support | 2014 |
| 1 Viper Ltd | Wholesale & retail | 2025 |
| 1 W Training Ltd | Professional & scientific | 2020 |
| 1 Waldeck Road Limited | Households | 2008 |
| 1 Wallenberg Place Limited | Professional & scientific | 2020 |
| 1 Waterhouse Square Tenant Limited | Real estate | 2018 |
| 1 Way Tech Solutions Limited | Construction | 2024 |
| 1 Wellington Place Limited | Wholesale & retail | 1991 |
| 1 Wendell RD Company Ltd | Real estate | 2012 |
| 1 West Heath Lodge Ltd | Real estate | 2018 |
| 1 West Road Care Ltd | Real estate | 2026 |
| 1 West Warwick Place Limited | Households | 2005 |
| 1 Westgate Terrace Management Limited | Households | 1991 |
| 1 Westminster Bridge Plaza Management Company Limited | Hospitality | 2005 |
| 1 Whitehall Ltd | Real estate | 2025 |
| 1 Wickham Road Limited | Other services | 2014 |
| 1 Wimbledon Park Road Management Limited | Households | 1999 |
| 1 WIN Limited | Administrative & support | 2006 |
| 1 Wisbech Road March Ltd | Construction | 2020 |
| 1 Wolseley Road Limited | Other services | 2009 |
| 1 Woodville Road Management Limited | Households | 2021 |
| 1 Wooler Street Limited | Extraterritorial | 2017 |
| 1 Woolstone RD Collective Ltd | Extraterritorial | 2006 |
| 1 World Impex Ltd | Wholesale & retail | 2020 |
| 1 Worlingham Road Limited | Households | 2020 |
| 1& Limited | Construction | 2025 |
| 1&ONLY Apparel Ltd | Wholesale & retail | 2025 |
| 1)ST Vincent Properties Limited | Real estate | 2026 |
| 1, 2 and 4 Marcus Terrace Residents Ltd | Real estate | 2012 |
| 1, 3 & 5 West Eaton Place (RTM) Limited | Households | 2011 |
| 1, Kidderpore Gardens Residents Association Limited | Households | 1962 |
| 1, Mabley Street London Limited | Households | 2019 |