| Lister Dental Clinic Ltd | Health & social care | 2025 |
| Litbrit Carpentry Limited | Construction | 2010 |
| Litigation Assist Limited | Professional & scientific | 2020 |
| Litkraft Ltd | Public administration | 2011 |
| Litter Aware Holdings Limited | Financial services | 2021 |
| Litter Aware International Limited | Information & communication | 2023 |
| Litter Aware Limited | Information & communication | 2020 |
| Little Acorns Theatre Academy Limited | Administrative & support | 2015 |
| Little London Ballet Ltd | Education | 2015 |
| Little Phoenix Kitchen Ltd | Hospitality | 2025 |
| Little Teepee Parties Limited | Hospitality | 2019 |
| Little Temptations Limited | Wholesale & retail | 1998 |
| LIV Bridging Finance Limited | Financial services | 2013 |
| Livelikeliv Ltd | Arts & recreation | 2024 |
| Living Kingdom Limited | Real estate | 2019 |
| Liviu&Chis Ltd | Construction | 2024 |
| Livnos Bayis Limited | Health & social care | 2021 |
| Livy&Co Limited | Administrative & support | 2013 |
| Liyana Solutions Ltd | Information & communication | 2016 |
| LIZ Hawkins Limited | Information & communication | 2014 |
| Ljmb Ltd | Construction | 2014 |
| LK Property Ventures Ltd | Real estate | 2019 |
| LKD Investments Limited | Administrative & support | 2023 |
| Llatini Brothers Ltd | Construction | 2020 |
| Llea UK Limited | Real estate | 2022 |
| LLJ Construction Limited | Construction | 2007 |
| Lloyd Allen Investments Limited | Real estate | 2017 |
| LM Creative Arts Ltd | Arts & recreation | 2019 |
| LM Studio Ltd | Professional & scientific | 2020 |
| LMA Hair Ltd | Other services | 2021 |
| LMG 1 Limited | Arts & recreation | 2009 |
| Lmrx Group Ltd | Wholesale & retail | 2026 |
| Loadz Ltd | Wholesale & retail | 2020 |
| Lobos Investments Limited | Administrative & support | 2013 |
| Loco Food Centre Chigwell Ltd | Wholesale & retail | 2025 |
| Locus Entertainment Limited | Arts & recreation | 2022 |
| Logan Sinclair Ltd | Administrative & support | 2012 |
| Logistic Intelligence Limited | Transport & logistics | 2012 |
| Logistrans (U.K.) Limited | Transport & logistics | 1994 |
| Logistrans Limited | Transport & logistics | 2018 |
| LOK Ming Food Ltd | Hospitality | 2024 |
| London Actonians Women Limited | Arts & recreation | 2026 |
| London Audio Visual Ltd | Extraterritorial | 2024 |
| London Barrelhouse Limited | Other services | 2019 |
| London Commercial Property Limited | Construction | 2020 |
| London Diamond Drilling Holdings Ltd | Financial services | 2014 |
| London Diamond Drilling Services Limited | Construction | 2017 |
| London Eggs UK Ltd | Wholesale & retail | 2025 |
| London Elite Electrical Ltd | Construction | 2011 |
| London Elite Electrical Services Ltd | Construction | 2020 |
| London Hernia and Colorectal Clinic Ltd | Health & social care | 2023 |
| London Keyhole Surgery Ltd | Health & social care | 2011 |
| London Plastic Surgeons Limited | Health & social care | 2002 |
| London Residential Assets Limited | Real estate | 2024 |
| London Residential Property Services Limited | Real estate | 2016 |
| London Residentials Limited | Administrative & support | 2004 |
| London Scene Limited | Construction | 1967 |
| London School of Hair & Beauty Training Ltd | Other services | 2013 |
| London Serviced Apartments Limited | Administrative & support | 1999 |
| Londonconstructionwork Ltd | Construction | 2022 |
| Londonest Ltd | Construction | 2023 |
| Longevity Oasis Ltd | Health & social care | 2023 |
| Longfield Avenue Freehold Limited | Real estate | 2021 |
| Lonsdale Court (Freehold) Limited | Households | 2009 |
| Looktdb Ltd | Administrative & support | 2023 |
| Lord Simpson Ventures Ltd | Professional & scientific | 2025 |
| LORDSHIP314 Limited | Real estate | 2025 |
| Loud Cat Productions Limited | Administrative & support | 2015 |
| Loughton Local Limited | Households | 2015 |
| Loutan Ltd | Wholesale & retail | 2024 |
| Loveworklife Consulting Limited | Professional & scientific | 2007 |
| Loving Bay Limited | Wholesale & retail | 2020 |
| LOW Tide Hospitality Limited | Administrative & support | 2025 |
| Lowtownstore Limited | Wholesale & retail | 2024 |
| LRD Investments Limited | Financial services | 2015 |
| LRG Property Ltd | Real estate | 2022 |
| Lsarchitects Limited | Professional & scientific | 2021 |
| Lshy Limited | Real estate | 2025 |
| LSR Salons Ltd | Wholesale & retail | 2024 |
| Lucinda K Design Ltd | Construction | 2020 |
| Lucjam London Limited | Hospitality | 2019 |
| Luckysix Limited | Administrative & support | 2006 |
| Lucy Hardcastle Studio Limited | Arts & recreation | 2016 |
| Lucy Superfox Ltd | Professional & scientific | 2017 |
| Luk.Inc 4 Properties Ltd | Real estate | 2025 |
| Lumasonic Ltd | Information & communication | 2025 |
| Lumena Scientific Communications Ltd | Professional & scientific | 2025 |
| Lumi Entertainment Limited | Administrative & support | 2009 |
| Lumibrite Labs Limited | Manufacturing | 2025 |
| Luminar Aesthetics Limited | Wholesale & retail | 2023 |
| Luna Education Limited | Education | 2022 |
| Luna Homes Limited | Households | 2022 |
| Luna Stone Ltd | Professional & scientific | 2025 |
| Lurean Ltd | Wholesale & retail | 2026 |
| Lushnikov Ltd | Professional & scientific | 2012 |
| Luudo Ltd | Information & communication | 2022 |
| Luvejuice Limited | Wholesale & retail | 2016 |
| Luvena Catering Ltd | Hospitality | 2024 |
| Luvexiha Ltd | Real estate | 2024 |
| LUX Asia Ltd | Hospitality | 2025 |