| Kamal Reporting and Imaging Services Limited | Health & social care | 2016 |
| Kandu Care Ltd | Health & social care | 2023 |
| Kandyfloss Vending Ltd | Administrative & support | 2006 |
| Kapaciti Ltd | Professional & scientific | 2014 |
| Kapsys Ltd | Information & communication | 2026 |
| Karen Bower-Brown Ltd | Professional & scientific | 2011 |
| Karenb Commercial Ltd | Professional & scientific | 2025 |
| Karg Devs Limited | Construction | 2023 |
| Karibu Rentals Ltd | Real estate | 2020 |
| Karls Karz Ltd. | Administrative & support | 2023 |
| KAS Cuisine Limited | Hospitality | 2016 |
| Kat-Oli Limited | Real estate | 2012 |
| Katalyse Group Ltd | Professional & scientific | 2026 |
| Katartizo Limited | Construction | 2024 |
| Kate Carr CBT Limited | Health & social care | 2015 |
| Kate Laurel Ltd | Other services | 2016 |
| Kate Martin Enterprises Ltd | Professional & scientific | 2014 |
| Kate Southwell CBT Limited | Health & social care | 2014 |
| Katie E Hill Limited | Professional & scientific | 2020 |
| Katies Dog Grooming Limited | Other services | 2023 |
| Katies Pet Services Limited | Other services | 2023 |
| Kausar Zaman Ltd | Wholesale & retail | 2025 |
| Kavanagh Plumbing & Heating Ltd | Construction | 2024 |
| Kavinnivin Ltd | Health & social care | 2025 |
| KAY ALE Limited | Hospitality | 2022 |
| KAY Cars (Lincoln) Limited | Transport & logistics | 2017 |
| KB Utilities (Lincs) Limited | Construction | 2016 |
| KBG Solutions Limited | Administrative & support | 2011 |
| KBS Carpentry Ltd | Construction | 2021 |
| KCH Q.S. Services Ltd | Professional & scientific | 2017 |
| KCH Separation Ltd | Professional & scientific | 2018 |
| KCJ Solutions Limited | Professional & scientific | 2015 |
| KCL Legal and Collections Limited | Other services | 2025 |
| KCS IT Limited | Information & communication | 2016 |
| KD Case Management Limited | Health & social care | 2010 |
| KD Joinery Ltd | Construction | 2023 |
| KD Retro Revival Ltd | Wholesale & retail | 2025 |
| Kdns Properties Limited | Real estate | 2019 |
| KDS24 Ltd | Administrative & support | 2026 |
| Kdsd Limited | Real estate | 2017 |
| KEB Properties Limited | Real estate | 2018 |
| Keells Groceries Ltd | Wholesale & retail | 2026 |
| Keevo Developments Ltd | Construction | 2021 |
| Keith Arnold Car Sales Limited | Wholesale & retail | 1999 |
| Kelarum Solutions Ltd | Professional & scientific | 2025 |
| Kelchin’ Films Ltd | Information & communication | 2026 |
| Kelleher Construction Limited | Construction | 2010 |
| Kellett Enterprises Limited | Financial services | 2022 |
| Kelly & Sons Transport Ltd | Transport & logistics | 2025 |
| Kelly Credland Ltd | Administrative & support | 2023 |
| Kelly Young Ltd | Construction | 2015 |
| Kelsey Entertainment Ltd | Information & communication | 2023 |
| Kelso Heights Properties Limited | Real estate | 2012 |
| Kemp & Kemp Consultancy Limited | Professional & scientific | 2013 |
| Kemsis Limited | Hospitality | 2015 |
| KEN Wallhead Ltd | Transport & logistics | 2023 |
| Kendricks Canine Services Ltd | Agriculture & fishing | 2019 |
| Kent Orthopaedics Limited | Health & social care | 2008 |
| Kent Pressureways Limited | Administrative & support | 2023 |
| Kernz Melts Ltd | Extraterritorial | 2023 |
| Kerrs Commerce Limited | Wholesale & retail | 2025 |
| Kersey Plastering Contractors Limited | Construction | 2012 |
| Kesteven Garden Services Limited | Administrative & support | 2026 |
| Kesteven Plastics Limited | Construction | 1981 |
| Kettels Consulting Limited | Professional & scientific | 2022 |
| Kettle and Black Ltd | Manufacturing | 2021 |
| Keverne & Gamble Ltd | Construction | 2016 |
| Kevin Cooke Business Services Limited | Professional & scientific | 2023 |
| Kevin Robinson Trucking (UK) Ltd | Transport & logistics | 2012 |
| Key and Sock Limited | Health & social care | 2024 |
| Key Technologies Limited | Professional & scientific | 2008 |
| Keycon Building Services Ltd | Construction | 2017 |
| Keyplace Limited | Wholesale & retail | 1995 |
| Keyqlix Ltd | Professional & scientific | 2023 |
| Keystone (KP) Properties Ltd | Real estate | 2024 |
| Keystone Property Solutions Limited | Construction | 2011 |
| Keyturn Lincoln Ltd | Construction | 2024 |
| Keywook Ltd | Construction | 2020 |
| KF Electrical (Lincoln) Ltd | Construction | 2015 |
| KFS Civil Engineering Ltd | Construction | 2017 |
| KG S and S Ltd | Information & communication | 2008 |
| KGM Recovery and Field Services Ltd | Health & social care | 2023 |
| KGP Roofing & Construction Limited | Construction | 2020 |
| KH Partnership Ltd | Wholesale & retail | 2016 |
| Khaled Ebeed Locum Ltd | Health & social care | 2025 |
| Khalids Enterprises Ltd | Health & social care | 2015 |
| Khloris Global Limited | Real estate | 2025 |
| Khushee Limited | Real estate | 2018 |
| KIC Property Limited | Real estate | 2020 |
| Kicks by Dott Ltd | Wholesale & retail | 2021 |
| Kicks Korner Arbitrage Ltd | Wholesale & retail | 2025 |
| Kiddovend Ltd | Wholesale & retail | 2025 |
| Kids Corner Day Nursery Limited | Education | 2012 |
| Kidz Cave Limited | Wholesale & retail | 2014 |
| Kidz Kitchen Ltd | Hospitality | 2012 |
| Kieron Price Ltd | Transport & logistics | 2013 |
| Kilcoyne Groundworks & Plant Hire Limited | Administrative & support | 2002 |
| Kilmore Civil Engineering Ltd. | Construction | 1997 |
| Kimanithebarber Ltd | Wholesale & retail | 2026 |
| Kimberley Rose Tuplin Ltd | Administrative & support | 2023 |