| Kuehne + Nagel (UK) Limited | Administrative & support | 1979 |
| Kuehne + Nagel Limited | Transport & logistics | 1983 |
| Kumacon Ltd | Professional & scientific | 2022 |
| Kunti Ltd | Health & social care | 2024 |
| Kuppi Ltd | Information & communication | 2024 |
| Kushdev Investments Ltd | Real estate | 2022 |
| Kushi PVT Ltd | Information & communication | 2023 |
| KVP London Limited | Transport & logistics | 2022 |
| KW Trade Solutions Limited | Professional & scientific | 2024 |
| KXL Autos Ltd | Wholesale & retail | 2022 |
| Kyriakides Lighting Ltd | Professional & scientific | 2025 |
| KZ Consulting and Investment Limited | Professional & scientific | 2024 |
| KZ Sports Ltd. | Arts & recreation | 2013 |
| L&K Top Ltd | Construction | 2023 |
| L&M Care and Training Services Limited | Education | 2024 |
| L.E.D.A Electrical Ltd | Construction | 2014 |
| L.M.J. Electronics Ltd | Professional & scientific | 2019 |
| L4 Property Investment Ltd | Real estate | 2020 |
| L4 Property Ltd | Real estate | 2025 |
| LA Jawaab London Ltd | Hospitality | 2024 |
| Labeirut Ltd | Hospitality | 2025 |
| Labhkunvar Properties Limited | Real estate | 2025 |
| Labq Limited | Information & communication | 2013 |
| Laced Ltd | Other services | 2025 |
| Laci Car Valeting Services Ltd | Administrative & support | 2022 |
| Laddu Box Limited | Hospitality | 2025 |
| Lady C Blessed Ltd | Health & social care | 2022 |
| Lakeside Blossoms Ltd. | Real estate | 2019 |
| Lakshmi Narayan PVT Ltd | Information & communication | 2025 |
| Lala Haulage Ltd | Transport & logistics | 2024 |
| Lambe & Sons Ltd | Real estate | 2022 |
| Lana Property Ltd | Manufacturing | 2025 |
| Landmark Global (UK) Limited | Transport & logistics | 1999 |
| Landmark Trade Services (UK) Limited | Transport & logistics | 2010 |
| Langridge Organic Products Limited | Manufacturing | 1993 |
| Lascount Ltd | Professional & scientific | 2013 |
| Laser Clinic Hounslow Ltd | Health & social care | 2017 |
| Lashentice Ltd | Other services | 2023 |
| Last Minute Deals Ltd | Wholesale & retail | 2012 |
| Lasting Impressions Food Company Limited | Manufacturing | 2005 |
| Lateral Capital Limited | Administrative & support | 2022 |
| Latini International Limited | Information & communication | 2014 |
| Lauche Consultants Limited | Information & communication | 2020 |
| Laura Hamblin Aesthetics Ltd | Other services | 2019 |
| Laurance Leon Limited | Wholesale & retail | 2024 |
| Laurmatt Ltd | Transport & logistics | 2024 |
| Lavender Recruitment Ltd | Administrative & support | 2024 |
| Lavish Looks Beauty Ltd | Other services | 2023 |
| LB Golbel Logistics Ltd | Transport & logistics | 2025 |
| LBW Consulting Group Limited | Education | 2026 |
| LC Property Investments (London) Ltd | Real estate | 2020 |
| LDN Reactive Property Maintenance Ltd | Construction | 2024 |
| LE Tour Knows Freight Limited | Transport & logistics | 2020 |
| Leadershiplive! CIC | Administrative & support | 2025 |
| Leafline Logistics Limited | Transport & logistics | 2025 |
| Leannes Boutique Ltd | Wholesale & retail | 2025 |
| Learnovation Limited | Education | 2024 |
| Lease Squad Ltd | Real estate | 2025 |
| Leds Properties Ltd | Real estate | 2025 |
| Ledsc Building Ltd | Construction | 2024 |
| Leela & JAY Property Investment Limited | Real estate | 2020 |
| Left Brain Digital Ltd | Professional & scientific | 2019 |
| Legaero Limited | Manufacturing | 2012 |
| Leisure 1 Limited | Real estate | 2022 |
| Leisure World Travels Nepal (UK) Limited | Administrative & support | 2023 |
| Leman Swans Ltd | Education | 2014 |
| Lengineering Ltd | Professional & scientific | 2020 |
| Leon Building Contractors Limited | Construction | 2015 |
| Letombo Limited | Health & social care | 2008 |
| Letombo Properties Limited | Real estate | 2022 |
| LF Commerce Ltd | Wholesale & retail | 2026 |
| LFC Construct Ltd | Construction | 2019 |
| LH Acrobatics Ltd | Education | 2021 |
| LHR Services Ltd Limited | Wholesale & retail | 2016 |
| Liberty Global Tours & Incentives Limited | Administrative & support | 2025 |
| Liberty International Events & Design Company Limited | Hospitality | 2025 |
| Licata Building Systems Limited | Wholesale & retail | 2012 |
| Liesel Angel Trust | Health & social care | 2012 |
| Life and Mind Coaching Academy Ltd | Education | 2024 |
| LIFT2LAUNCH Ltd | Information & communication | 2025 |
| Lifted & Listed Ltd | Real estate | 2025 |
| Liftstore Limited | Professional & scientific | 2001 |
| Lightmax Productions Ltd | Administrative & support | 2023 |
| Lightningship UK Store Limited | Wholesale & retail | 2020 |
| Lika Companies Ltd | Hospitality | 2019 |
| Lily Gardens Ltd | Administrative & support | 2021 |
| Limitless Consultancy Ltd | Administrative & support | 2017 |
| Line V Development Ltd | Construction | 2024 |
| Line V Limited | Construction | 2022 |
| Linex Construction Ltd | Construction | 2024 |
| Ling & Sons Limited | Construction | 1969 |
| Ling Holdings Ltd | Financial services | 2021 |
| Ling Residential Ltd | Real estate | 2021 |
| Lingden Limited | Hospitality | 2018 |
| Link Cargo Services Limited | Transport & logistics | 2025 |
| Lionspoon Ltd | Hospitality | 2017 |
| Lipi Graphics Ltd | Information & communication | 2014 |
| Lisboa Loja Ltd | Hospitality | 2018 |
| Lite and Direct Maintenance Ltd | Construction | 2026 |
| Little SIP Limited | Hospitality | 2015 |