| Just Like Mumma's Ltd | Hospitality | 2014 |
| Just Reasonable Ltd | Professional & scientific | 2016 |
| Just Storage Limited | Real estate | 2014 |
| Just Trends Ltd | Wholesale & retail | 2018 |
| Just US PO Ltd | Financial services | 2023 |
| Just US Retail Ltd | Wholesale & retail | 2020 |
| JUST4U Allrounder Trading Ltd | Administrative & support | 2020 |
| JUST4WASH Ltd | Administrative & support | 2023 |
| Justa 07 Ltd | Transport & logistics | 2025 |
| Justellade Accountancy Ltd | Professional & scientific | 2017 |
| Justellade Recruitment Ltd | Administrative & support | 2018 |
| Justin Site Services Ltd | Water & waste | 2026 |
| Justin Williams Windows LLP | | 2018 |
| JV Medtech Consulting Ltd | Professional & scientific | 2026 |
| JVC Holdings Ltd | Financial services | 2025 |
| Jwalit Limited | Information & communication | 2025 |
| JWW Ltd | Construction | 2022 |
| K & D Property Holdings Ltd | Financial services | 2020 |
| K & J Carpets Limited | Wholesale & retail | 1996 |
| K & N Accountants Ltd | Professional & scientific | 2021 |
| K a W Marketing Limited | Administrative & support | 2013 |
| K and S Childcare Limited | Education | 2008 |
| K F Kitchens Ltd | Wholesale & retail | 2008 |
| K K Controls and Equipment Ltd | Manufacturing | 2004 |
| K L Ross Limited | Administrative & support | 2013 |
| K M S Property Solutions Ltd. | Real estate | 2013 |
| K R Construction Services Ltd | Construction | 2024 |
| K Star Barbers Ltd | Other services | 2022 |
| K&D Nails Limited | Other services | 2018 |
| K&Pwindows Ltd | Wholesale & retail | 2026 |
| K&S Security Ltd | Administrative & support | 2021 |
| K&S Textiles Limited | Wholesale & retail | 2025 |
| K.D.B. Construction Limited | Wholesale & retail | 1989 |
| K.M. Builders | | 2002 |
| K.P.T (SW) Limited | Water & waste | 2003 |
| K2 Carpentry Ltd | Manufacturing | 2026 |
| K9 Meals on Wheels Ltd | Hospitality | 2011 |
| Kabb Ltd | Professional & scientific | 2025 |
| Kabul Flames Limited | Hospitality | 2025 |
| KAC & Associates Limited | Real estate | 2023 |
| Kadampa Meditation Centre Plymouth Ltd | Other services | 1997 |
| Kadan International Ltd | Construction | 2018 |
| Kader Property Management Ltd | Administrative & support | 2016 |
| Kahlo Property Lets Ltd | Real estate | 2021 |
| KAI JU Engineering Ltd. | Manufacturing | 2015 |
| Kaila Stone UK Limited | Wholesale & retail | 2015 |
| Kaipara Ltd | Real estate | 2023 |
| Kairomics Ltd | Information & communication | 2026 |
| Kaizus Hub Limited | Wholesale & retail | 2026 |
| Kalidoma Ltd | Real estate | 2026 |
| Kalin Spasov Limited | Professional & scientific | 2025 |
| Kalirai & Ogilvie Properties Limited | Real estate | 2023 |
| Kallis Holdings Limited | Real estate | 2026 |
| Kallis Homes Ltd | Real estate | 2019 |
| KALNET4U Limited | Information & communication | 2003 |
| Kama Express Limited | Hospitality | 2024 |
| Kamaie Properties Limited | Construction | 2011 |
| Kami Quality Developments SW Ltd | Construction | 2023 |
| Kamil's Counselling and Psychotherapy Limited | Health & social care | 2025 |
| Kamzi Limited | Hospitality | 2025 |
| Kangrosa Limited | Wholesale & retail | 2018 |
| Kantebeen Limited | Professional & scientific | 2016 |
| Kaos Production Ltd | Administrative & support | 2009 |
| Kapf Limited | Professional & scientific | 2024 |
| Kapture Photography Limited | Professional & scientific | 2010 |
| Karak Chaii Exeter Ltd | Hospitality | 2025 |
| Karak Chaii Plymouth Ltd | Hospitality | 2024 |
| Karate in the Community CIC | Education | 2023 |
| Karib FX Ltd | Financial services | 2022 |
| Karim Financial Ltd | Financial services | 2022 |
| Karl James Ltd | Arts & recreation | 2022 |
| Karlenn Limited | Construction | 2018 |
| Karlyon Care Limited | Health & social care | 2009 |
| Karma Hair and Tanning Studio Limited | Other services | 2005 |
| Karpet Limited | Hospitality | 2020 |
| Karri Investments Ltd | Professional & scientific | 2021 |
| Karris Networks Limited | Information & communication | 2016 |
| Kartal Kara & Sons Ltd | Hospitality | 2019 |
| Kassidy Lifestyle Limited | Wholesale & retail | 2017 |
| Kassilly Consult Limited | Hospitality | 2025 |
| KAT Star Cleaning Services Ltd | Administrative & support | 2021 |
| Kat's Kreatures Ltd | Other services | 2024 |
| Kate Smith Insights Ltd | Professional & scientific | 2025 |
| Katie&James Ltd | Manufacturing | 2026 |
| Katori Grooming Salon Limited | Other services | 2017 |
| Katstore Limited | Wholesale & retail | 2019 |
| Kaushik Transport Ltd | Transport & logistics | 2025 |
| Kawasaki Precision Machinery (UK) Limited | Manufacturing | 1993 |
| KAY B and Co Hair and Beauty Ltd | Other services | 2021 |
| KAY Care Agency Ltd | Public administration | 2020 |
| Kaziu & Van Ltd | Transport & logistics | 2020 |
| KB Boiler and Controls Limited | Construction | 2014 |
| KB Carpentry and Joiners Ltd | Construction | 2025 |
| KB Products Limited | Extraterritorial | 2003 |
| KB Services & Consultancy Ltd | Professional & scientific | 2021 |
| Kbddrawings Limited | Professional & scientific | 2019 |
| KBH Motorcycles Ltd | Wholesale & retail | 2013 |
| KC Consulting Solutions Limited | Administrative & support | 2015 |
| Kc's Pubs Limited | Hospitality | 2025 |
| Kcds Engineering Limited | Construction | 2016 |