| KHC Property Development Limited | Real estate | 2018 |
| Killy Lane Development Management Ltd | Households | 2018 |
| Kilnstar Limited | Professional & scientific | 2005 |
| Kinderman Consulting Limited | Professional & scientific | 2016 |
| Kindfullspace CIC | Health & social care | 2026 |
| Kinema Works Ltd | Information & communication | 2025 |
| Kings & Crooks Ltd | Wholesale & retail | 2020 |
| Kings Builders Ltd | Construction | 2008 |
| Kings Court (Bridlington) Management Company Limited | Households | 2011 |
| Kings Gym Limited | Arts & recreation | 2022 |
| Kings Reach Management Company Limited | Real estate | 2002 |
| Kingsland Property Consultants Ltd | Real estate | 2025 |
| Kingswinford Locks Holdings Ltd | Manufacturing | 2002 |
| Kingswood Wealth Management Limited | Financial services | 2011 |
| Kinsoncompany Limited | Wholesale & retail | 2019 |
| Kintsugi Living Ltd | Real estate | 2025 |
| Kippy Properties Ltd | Real estate | 2024 |
| Kirkbrides Essence and Beauty Distribution Ltd | Wholesale & retail | 2025 |
| Kirkham Part Exchange Centre Limited | Wholesale & retail | 2022 |
| Kirkhamashton Partners Ltd | Real estate | 2025 |
| Kirkstone Group Limited | Financial services | 2020 |
| Kirwin Construction & Groundworks Ltd | Construction | 2024 |
| Kiswa Group Ltd | Real estate | 2026 |
| KK Mart Ltd | Wholesale & retail | 2026 |
| KKP Kamil Khan Properties Ltd | Construction | 2025 |
| KL FINANCE24 Ltd | Health & social care | 2024 |
| KL Property Partners Ltd | Real estate | 2023 |
| Klarity Trading Ltd | Wholesale & retail | 2025 |
| KLM Orthodontics Limited | Health & social care | 2018 |
| KLN Motors Limited | Wholesale & retail | 2021 |
| KM Online Limited | Wholesale & retail | 2015 |
| KN Investments Ltd | Real estate | 2024 |
| Knead IT Massage Ltd | Other services | 2023 |
| Knellor Road Ltd | Administrative & support | 2017 |
| Knight Kavanagh & Page Limited | Professional & scientific | 2014 |
| Knight Premier Investments Limited | Financial services | 2021 |
| Knightmedia Ltd | Information & communication | 2024 |
| Knighton Developments Limited | Administrative & support | 1999 |
| Knightsbridge Estates NW Ltd | Real estate | 2020 |
| Know and DO Limited | Professional & scientific | 2010 |
| Knowsley Capital Limited | Construction | 2019 |
| Knutsford Road Development Ltd | Construction | 2022 |
| Koeys Homes Ltd | Real estate | 2025 |
| Kohima Partners Limited | Professional & scientific | 2021 |
| Komegloba Limited | Wholesale & retail | 2024 |
| Konnect Smart Ltd | Administrative & support | 2020 |
| KONYHA24 Ltd | Hospitality | 2024 |
| Kooli Traders Ltd | Wholesale & retail | 2026 |
| Kooruna Investments Ltd | Real estate | 2024 |
| Kore Reformer & Hot Yoga Limited | Arts & recreation | 2024 |
| Koru Collective Limited | Professional & scientific | 2022 |
| Korwoods Properties Ltd | Real estate | 2017 |
| Kostice Properties Ltd | Real estate | 2025 |
| Kota E Commerce Limited | Wholesale & retail | 2025 |
| Kothai Properties Limited | Real estate | 2022 |
| Kotton Inc Limited | Wholesale & retail | 2019 |
| KPA Support Ltd | Administrative & support | 2018 |
| KPG Wood Ltd | Manufacturing | 2026 |
| KRA 2009 Limited | Wholesale & retail | 2009 |
| Krafte Tuning Ltd | Wholesale & retail | 2024 |
| Krakow Grocery 1 Ltd | Wholesale & retail | 2024 |
| Kreamy Kreams Limited | Wholesale & retail | 2013 |
| Kristian Allan Lettings Limited | Real estate | 2011 |
| Kristian Allan Sales Limited | Real estate | 2016 |
| KRP Ventures Limited | Hospitality | 2019 |
| Krung Theph Ltd | Hospitality | 2023 |
| Krupa Engineering Limited | Manufacturing | 2003 |
| KS & RY Ltd | Real estate | 2025 |
| KS Taverns Ltd | Hospitality | 2017 |
| KSA Media Ltd | Professional & scientific | 2023 |
| KT Cleaning & Building Services Ltd | Construction | 2026 |
| Kudos QA Limited | Professional & scientific | 2019 |
| KUNNI565 Ltd | Real estate | 2026 |
| Kurdish Razor Sharp Ltd | Other services | 2024 |
| Kurdistan Fade Ltd | Other services | 2026 |
| Kurehomecare Ltd | Health & social care | 2026 |
| Kuti Klean Ltd | Administrative & support | 2018 |
| Kuyog Ltd | Professional & scientific | 2024 |
| KV Care Limited | Other services | 2018 |
| KVF Projects Ltd | Professional & scientific | 2024 |
| KW Carbon Consulting Ltd | Professional & scientific | 2023 |
| KW Services Northern Ltd | Real estate | 2013 |
| KWC Courier & Removal Ltd | Transport & logistics | 2025 |
| Kwik Couriers Ltd | Transport & logistics | 2026 |
| Kwik FIX Phones Bury Limited | Wholesale & retail | 2025 |
| Kwoff Limited | Wholesale & retail | 2014 |
| Kyte Renovations Ltd | Manufacturing | 2026 |
| L & G Skip Hire Limited | Administrative & support | 2008 |
| L & J R Energy Solutions Ltd | Construction | 2022 |
| L & L Investment Holdings Limited | Financial services | 2023 |
| L & S Installations Ltd | Transport & logistics | 2023 |
| L C Maxwell Consultancy Limited | Professional & scientific | 2019 |
| L E Turner Properties Limited | Real estate | 2019 |
| L Greenhalgh Consulting Ltd | Professional & scientific | 2019 |
| L J G Holdings Ltd | Real estate | 2022 |
| L J Molloy Ltd | Extraterritorial | 1996 |
| L&L Jenks Ltd | Health & social care | 2023 |
| L&M Engineering NW Ltd | Professional & scientific | 2025 |
| L&R Business Finance Limited | Financial services | 2023 |
| L'N'K Motors Ltd | Wholesale & retail | 2014 |