| KEN Ideson Joiners Ltd | Construction | 2005 |
| Kenneth Brown Bulk Liquids (Holdings) Limited | Financial services | 2022 |
| Kenneth Brown Bulk Liquids Limited | Wholesale & retail | 1979 |
| Kerry Ultrasonics Limited | Extraterritorial | 1957 |
| Kesic Dispensing Limited | Wholesale & retail | 2025 |
| Kettlesing Enterprises Ltd. | Extraterritorial | 2006 |
| Kettlewell Catering Limited | Hospitality | 2018 |
| Kettlewell Manor Limited | Professional & scientific | 1954 |
| Kettlewell Overlords Limited | Professional & scientific | 1954 |
| Kettu Studios Ltd | Information & communication | 2020 |
| Key Farm Feeds Ltd | Administrative & support | 2023 |
| Kibble Bakery Ltd | Hospitality | 2017 |
| Kilmartin Orthotics Ltd | Health & social care | 2024 |
| Kilnsey Park Limited | Agriculture & fishing | 2021 |
| Kime+ Nutrition Ltd | Wholesale & retail | 2025 |
| Kindacademy Ltd | Information & communication | 2020 |
| Kindaco Ltd | Manufacturing | 2019 |
| King Cole Limited | Wholesale & retail | 1998 |
| Kings Mill Settle Management Company Limited | Households | 2003 |
| Kingscroft CT Ltd | Real estate | 2020 |
| Kingsley House Developments Limited | Construction | 2003 |
| Kinship Care Services Ltd | Health & social care | 2026 |
| KIT Mill Ltd | Information & communication | 2023 |
| KJM Financial Limited | Financial services | 2011 |
| KKM Law Limited | Administrative & support | 2026 |
| Kmec Colne LLP | | 2018 |
| Kmec Skipton LLP | | 2019 |
| Knotty Joinery Limited | Construction | 2024 |
| Knowledge for Change Ltd. | Professional & scientific | 2012 |
| Knowles House Limited | Financial services | 2022 |
| Kookie & ME Creations Limited | Wholesale & retail | 2023 |
| KP Holdco Ltd | Financial services | 2021 |
| KRM Pharma Ltd | Professional & scientific | 2025 |
| KT Fitness and Nutrition Limited | Other services | 2015 |
| KU Bathrooms and Kitchens Ltd | Wholesale & retail | 2003 |
| Kupezare Constance 0574 Limited | Administrative & support | 2014 |
| Kyogikan Limited | Arts & recreation | 2004 |
| L a Comms Ltd | Information & communication | 2009 |
| L Danby Plumbing Ltd | Construction | 2021 |
| L Pennick (Plumbing & Heating) Services Ltd | Construction | 2019 |
| L.P.E Islay Limited | Administrative & support | 2012 |
| LA Cantina Direct Limited | Administrative & support | 2019 |
| Labcenter Electronics Limited | Information & communication | 2003 |
| Labcenter International LLP | | 2014 |
| Labelprint.Com Ltd | Manufacturing | 2024 |
| Labelverse Ltd | Information & communication | 2024 |
| Labhr Limited | Professional & scientific | 2010 |
| Labsoft UK Ltd | Information & communication | 2020 |
| Lady Lpa's Ltd | Financial services | 2026 |
| Lamados Limited | Administrative & support | 2021 |
| Lamberts Transport and Engineering Ltd | Transport & logistics | 2013 |
| Lancashire Gymnastics Ltd | Education | 2025 |
| Lane END Rentals Limited | Real estate | 2021 |
| Lash Candy Ltd | Other services | 2019 |
| Latitude 53 Solutions Ltd | Information & communication | 2001 |
| Laugh Learn Love Languages Limited | Education | 2014 |
| Lauradale Limited | Construction | 2023 |
| Lawton Media Ltd | Professional & scientific | 2023 |
| LBL Aesthetics Ltd | Other services | 2023 |
| LCA Consulting Limited | Professional & scientific | 2011 |
| LE Bistro DES Amis Limited | Hospitality | 2021 |
| LE Caveau (Skipton) Limited | Hospitality | 2014 |
| Lean Into Clean Limited | Wholesale & retail | 2023 |
| Lean Into Clean Media Limited | Information & communication | 2023 |
| Leanr Limited | Information & communication | 2017 |
| Leeming Developments Limited | Construction | 2022 |
| Lees Mill Management Company Limited | Administrative & support | 2003 |
| Lemons Skipton Limited | Hospitality | 2018 |
| Lemons Takeaway Fast Food Ltd | Hospitality | 2024 |
| LER Commercial Solutions Ltd | Hospitality | 2026 |
| LET Holdings Ltd | Financial services | 2018 |
| Lets GET Moving CIC | Education | 2021 |
| Level 37 Recordings Ltd | Information & communication | 2024 |
| Levitate Architecture and Design Studio Limited | Professional & scientific | 2000 |
| Levitate Architecture North Limited | Professional & scientific | 2011 |
| Lewiatan Limited | Wholesale & retail | 2016 |
| LHM (Holdings) Ltd | Professional & scientific | 2007 |
| Liam Best Limited | Arts & recreation | 2026 |
| Liam Jameson Ltd | Construction | 2016 |
| Liberte Ltd | Wholesale & retail | 2022 |
| Library Distribution Limited | Manufacturing | 2001 |
| Lidgard Heritage Consulting Ltd | Arts & recreation | 2025 |
| Linchpin Limited | Professional & scientific | 2005 |
| Linton Laithe Limited | Hospitality | 2017 |
| Liquidum Marketing Ltd | Professional & scientific | 2025 |
| Literate Technologies Limited | Education | 2026 |
| Little Feet Creche C.I.C. | Health & social care | 2018 |
| Little Windmill Limited | Real estate | 2022 |
| Little Worlds Imagine Ltd | Health & social care | 2026 |
| Littondale Properties Ltd | Real estate | 2024 |
| Live Breathe Limited | Other services | 2022 |
| Living Gardens Landscapes Ltd | Administrative & support | 2016 |
| Livingstone Villas Management Limited | Households | 2001 |
| LKW Education Limited | Education | 2024 |
| Lodfield Limited | Manufacturing | 1973 |
| Logovisual Ltd | Professional & scientific | 2000 |
| Loki Lettings Ltd | Real estate | 2025 |
| Longford Holdings Ltd | Professional & scientific | 1982 |
| Longford Hope & Co (Accountants) Limited | Professional & scientific | 1992 |
| Look Open Systems Limited | Information & communication | 2014 |