| LG Ecom Ltd | Financial services | 2019 |
| Lgmbsv Limited | Health & social care | 2021 |
| LGP & CDK Limited | Administrative & support | 2021 |
| Lgre Limited | Real estate | 2023 |
| Lgsm Hygiene and Therapy Limited | Professional & scientific | 2012 |
| LH Content Services Ltd | Professional & scientific | 2018 |
| LH Copywriting Limited | Arts & recreation | 2018 |
| LHS Productions Limited | Information & communication | 2012 |
| Liam David Limited | Wholesale & retail | 1993 |
| Liamsen Ltd | Professional & scientific | 2023 |
| Libertyconsulting (UK) Limited | Administrative & support | 2012 |
| Liduma Civils Ltd | Construction | 2024 |
| Lieberman Limited | Administrative & support | 2015 |
| Life Balance Essentials UK Ltd | Wholesale & retail | 2023 |
| Life Dynamics Limited | Administrative & support | 2008 |
| Life Sciences International Limited | Professional & scientific | 1979 |
| Life Technologies BPD UK Limited | Manufacturing | 1999 |
| Lifestyle Strides CIC | Education | 2023 |
| Lifetime Quality Roofing Ltd | Construction | 2023 |
| Light & Wall Limited | Administrative & support | 2022 |
| Light Words Limited | Administrative & support | 2025 |
| Lightbulb Leadership Solutions Limited | Education | 2007 |
| Lightfern Ltd | Information & communication | 2025 |
| Lightstone Day Nurseries LLP | | 2018 |
| Lightstone Denby Dale LLP | | 2018 |
| Lightstone Dundee LLP | | 2017 |
| Lightstone Fryers Way LLP | | 2009 |
| Lightstone Income LLP | | 2019 |
| Lightstone Income Management Ltd | Financial services | 2019 |
| Lightstone Islington LLP | | 2014 |
| Lightstone Kirkcaldy LLP | | 2017 |
| Lightstone Lundie Avenue LLP | | 2019 |
| Lightstone Neatscourt Phase 3 LLP | | 2018 |
| Lightstone Oswestry LLP | | 2021 |
| Lightstone POD Portfolio LLP | | 2016 |
| Lightstone Properties Limited | Construction | 2002 |
| Lightstone Rainham LLP | | 2021 |
| Lightstone Regency Heights LLP | | 2021 |
| Lightstone Stirling LLP | | 2017 |
| Lightstone Willerby LLP | | 2017 |
| Lightstone Wimpole Street LLP | | 2014 |
| Lightweight Consulting Limited | Administrative & support | 2011 |
| LILKAT7 Ltd | Financial services | 2026 |
| Lilley's Healthcare Limited | Professional & scientific | 2003 |
| Lilssy Limited | Professional & scientific | 2020 |
| Lily Care Ltd | Health & social care | 2002 |
| Lily PAD Property Management Ltd | Hospitality | 2023 |
| Lima North RD Limited | Construction | 2021 |
| Limbs Music Limited | Arts & recreation | 2021 |
| Limeblue Investments Limited | Real estate | 2007 |
| Limeculture C.I.C. | Professional & scientific | 2011 |
| Limehurst Estates Limited | Real estate | 2017 |
| Limes Trading Ltd | Other services | 2026 |
| Liminal Biosciences Holdings Limited | Financial services | 2015 |
| Liminal Biosciences Limited | Manufacturing | 2015 |
| Liminos Ltd | Professional & scientific | 2023 |
| Limited AH Limited | Administrative & support | 2019 |
| Limoncello HAT Limited | Real estate | 2020 |
| Lin's Investment Ltd | Real estate | 2021 |
| Linberg Design Associates Limited | Professional & scientific | 2006 |
| Lincoln Marks Motor Company Limited | Wholesale & retail | 2003 |
| Linden Grange Residents Company Limited | Households | 2003 |
| Lindisfarne Consulting Limited | Professional & scientific | 2011 |
| Lindley Westgate Services Limited | Other services | 2015 |
| Lindsay Hill House Flat Management Company Limited | Households | 2001 |
| Lindsell Associates Ltd | Education | 2010 |
| Lindum Investments Limited | Real estate | 1999 |
| Linea Health and Safety Ltd | Extraterritorial | 2021 |
| Linear Living (Talbot Road Block a) Ltd | Construction | 2023 |
| Linear Living (Talbot Road) Ltd | Construction | 2023 |
| Linear Living Lord Street Holdings Ltd | Construction | 2025 |
| Linear Living Lord Street JV Ltd | Construction | 2025 |
| Linear Living Lord Street Ltd | Construction | 2025 |
| Linear Living Ltd | Households | 2020 |
| Lineflow Limited | Administrative & support | 2000 |
| Lines Henry Ltd | Professional & scientific | 2005 |
| Link Electrical Services (NW) Limited | Manufacturing | 2009 |
| Link Health Group Limited | Professional & scientific | 2020 |
| Linken Projects (Design & Build) Ltd | Construction | 2023 |
| Linkythinks Ltd | Education | 2015 |
| Lino Corp Limited | Professional & scientific | 2023 |
| Lion & OWL Properties Ltd | Real estate | 2016 |
| Lion Kong Limited | Hospitality | 2022 |
| Lion Mill Investment Ltd | Real estate | 2023 |
| Lion Rock Events Ltd | Professional & scientific | 2023 |
| Lionsmane Software Services Limited | Information & communication | 2016 |
| Lionsource Ltd | Wholesale & retail | 2024 |
| LIP and Line Clinic Ltd | Health & social care | 2025 |
| Lips and Lines Aesthetics Limited | Other services | 2019 |
| LIR Therapeutics Limited | Professional & scientific | 2024 |
| Lisanderqorri Limited | Administrative & support | 2019 |
| Lischa Limited | Administrative & support | 1997 |
| Lister Aircraft Services Limited | Professional & scientific | 2026 |
| Lite Rite Limited | Administrative & support | 2004 |
| Lithium Capital Limited | Professional & scientific | 2014 |
| Litigate Direct Ltd | Professional & scientific | 2024 |
| Litmus Limited | Professional & scientific | 2024 |
| Little Angels Swim School Limited | Education | 2012 |
| Little Caesar UK Limited | Administrative & support | 2023 |
| Little Cloud Computing Ltd | Information & communication | 2019 |