| JDC Design Limited | Other services | 2016 |
| Jdhe Projects Ltd | Construction | 2017 |
| JDI Yorkshire Ltd | Administrative & support | 2017 |
| JDR Cooling & Energy Ltd | Manufacturing | 2014 |
| Jenny B Limited | Professional & scientific | 2012 |
| JES Design Consultancy Limited | Professional & scientific | 2013 |
| JI Logistics Ltd | Other services | 2020 |
| Jill Walmsley Agencies Limited | Wholesale & retail | 2020 |
| JIM Granger Architecture and Design Ltd | Professional & scientific | 2014 |
| JIS Venture Limited | Professional & scientific | 2020 |
| JL Joinery & Sealants Ltd | Construction | 2023 |
| JLD Insulation Limited | Construction | 2009 |
| JO Boothroyd Driver Training Ltd | Education | 2024 |
| John Croft Builders Limited | Construction | 2003 |
| John Drury & Co. Limited | Manufacturing | 1964 |
| Johnsons Foodservice Limited | Wholesale & retail | 2020 |
| Josh Kilmartin Limited | Wholesale & retail | 2010 |
| JP BAG Sealing Optimisation Services Ltd | Administrative & support | 2022 |
| JRB Properties Leeds Limited | Real estate | 2016 |
| JRC Distributions Ltd | Wholesale & retail | 2025 |
| JRF Commercials Limited | Wholesale & retail | 2017 |
| Juno&Pip Ltd | Wholesale & retail | 2026 |
| Just Check Ltd | Health & social care | 2022 |
| Juval Limited | Real estate | 2024 |
| JWA Properties Limited | Real estate | 2018 |
| K Brickwork Ltd | Construction | 2014 |
| K J C Developments (Yorkshire) Ltd | Real estate | 2024 |
| K L H Developments Limited | Construction | 1989 |
| Kafe Rose Ltd | Hospitality | 2022 |
| Kanzeus Ltd | Hospitality | 2025 |
| Karla K Ltd | Wholesale & retail | 2025 |
| Kate Fagan Ltd | Professional & scientific | 2024 |
| Katie Ormerod UK Ltd | Arts & recreation | 2017 |
| Kaur Investments Ltd | Real estate | 2021 |
| Kboutiquestyle Online Limited | Wholesale & retail | 2022 |
| KDM Luxury Properties Ltd | Real estate | 2023 |
| Kenwood Harrogate Limited | Construction | 2018 |
| Kepaderm Limited | Health & social care | 2020 |
| Kerr Educational Psychology Limited | Education | 2021 |
| KG Estate Planning Ltd | Other services | 2025 |
| Khan Spice Takeaway Ltd | Hospitality | 2021 |
| KHLOES9CT Limited | Wholesale & retail | 2023 |
| Khloescollection Ltd | Wholesale & retail | 2026 |
| Kidney Research Yorkshire Limited | Professional & scientific | 2004 |
| Kind Roots Inclusive Services CIC | Education | 2025 |
| Kinda Communities CIC | Education | 2024 |
| Kinect Card Limited | Information & communication | 2020 |
| Kingdom Business Coaching Limited | Professional & scientific | 2013 |
| Kingfisher Capital Limited | Real estate | 2019 |
| Kingfisher Equity Limited | Real estate | 2019 |
| Kingfisher Property (Yorkshire) Limited | Real estate | 2023 |
| Kipmcgrath (Brighouse) LP | | 2013 |
| Kirk Coastal Properties Ltd | Real estate | 2026 |
| Kirklees Hall Management Limited | Households | 1998 |
| Kirsty Louise Macleod Logistics Limited | Transport & logistics | 2025 |
| KIT Management Limited | Professional & scientific | 2026 |
| KLH Projects Ltd. | Construction | 2001 |
| Knavesmire Butchers Limited | Wholesale & retail | 2019 |
| Kraken Investments Ltd | Financial services | 2019 |
| Kramers Designs & Signs Limited | Professional & scientific | 2008 |
| Ksai Limited | Health & social care | 2020 |
| KT Construction (Leeds) Ltd | Construction | 2025 |
| Ktjewellery Limited | Manufacturing | 2026 |
| L Hartley's Roofing Ltd | Construction | 2022 |
| L J Heffernan Utilities Limited | Construction | 2016 |
| L M Speech and Language Therapy LLP | | 2015 |
| L Woollard Ltd | Administrative & support | 2013 |
| LA Carusa Limited | Wholesale & retail | 2025 |
| Lake House Investments Limited | Real estate | 2009 |
| Landau Land Limited | Real estate | 2001 |
| Landing Property Limited | Real estate | 2019 |
| Lands House Limited | Households | 2021 |
| Landsdown Recruitment Limited | Administrative & support | 2021 |
| Lane Orthodontics Limited | Health & social care | 2023 |
| Larner-Johnson Limited | Extraterritorial | 2015 |
| Latb Ltd | Real estate | 2014 |
| Lawrence Lift & Escalator Consultants Limited | Professional & scientific | 2007 |
| LDC Decorating Contractors Ltd | Construction | 2012 |
| LE Gourmet Pork PIE and Deli Ltd | Hospitality | 2026 |
| League Publications Limited | Information & communication | 1990 |
| LEE Decorating Ltd | Hospitality | 2023 |
| Leeds Raptors Ice Hockey Club Ltd | Arts & recreation | 2025 |
| Lentex (UK) Ltd | Wholesale & retail | 2004 |
| LEO Cycling Support Limited | Administrative & support | 2019 |
| Lethamm Properties Limited | Real estate | 2016 |
| Letterfactor Limited | Professional & scientific | 1993 |
| Letting Genie Ltd | Real estate | 2020 |
| Level 8 Ventures Limited | Hospitality | 2025 |
| LFS Electrical Limited | Manufacturing | 2025 |
| LHH Brighouse Ltd | Hospitality | 2024 |
| Liberty Glass Ltd | Manufacturing | 2011 |
| Libzbars Ltd | Hospitality | 2026 |
| Lifestyle Laser and Beauty Ltd | Other services | 2022 |
| Lightcliffe Mini Market Ltd | Wholesale & retail | 2023 |
| Lights on International Consulting Limited | Professional & scientific | 2021 |
| Lillands Lane Management Company Limited | Administrative & support | 2014 |
| Limelight Theatre Entertainment Limited | Arts & recreation | 2016 |
| Lindley Fine Wines Limited | Wholesale & retail | 2007 |
| Ling Leisure Ltd | Arts & recreation | 2020 |
| Liquid Catering Limited | Hospitality | 2016 |