| King Essentials Ltd | Wholesale & retail | 2025 |
| King's Driven Ltd | Education | 2017 |
| Kingbee Securities Limited | Construction | 1994 |
| Kingco Limited | Construction | 2014 |
| Kingdom Grace International Church | Other services | 2013 |
| Kingdomhoneyproducts Ltd | Wholesale & retail | 2025 |
| Kingfisher Aquatics Limited | Wholesale & retail | 2004 |
| Kingsclere Place Management Company Limited | Households | 2000 |
| Kingsley Capital Investments Limited | Households | 2025 |
| Kingsley Lane Ltd | Construction | 2019 |
| Kingsman-Accountants Limited | Professional & scientific | 2009 |
| Kingsmead Property Limited | Real estate | 2007 |
| Kingsmead School | Education | 2010 |
| Kingston Turkuaz Limited | Real estate | 2022 |
| Kingswood Chase Residents Company Limited | Households | 2007 |
| Kingswood Close Management Company Limited | Households | 1992 |
| Kingswood Manor Residents Company Limited | Households | 2007 |
| Kinnect Management Limited | Information & communication | 2019 |
| Kinrey Site Services Limited | Construction | 2015 |
| Kinworth Ltd | Wholesale & retail | 2026 |
| KIP Construction Consultancy Ltd | Construction | 2020 |
| Kircicek Ltd | Other services | 2020 |
| Kirkisrak Community House | Health & social care | 2008 |
| Kisas Group Ltd | Hospitality | 2026 |
| Kismet Homes Limited | Real estate | 2024 |
| Kiss the Hippo Berners Limited | Administrative & support | 2023 |
| Kiss the Hippo Bloomsbury Limited | Administrative & support | 2024 |
| Kiss the Hippo Cannon Limited | Administrative & support | 2025 |
| Kiss the Hippo Coffee Limited | Administrative & support | 2017 |
| Kiss the Hippo Covent Ltd | Administrative & support | 2023 |
| Kiss the Hippo Fitzrovia Limited | Administrative & support | 2019 |
| Kiss the Hippo Kiosk Limited | Administrative & support | 2019 |
| Kiss the Hippo Marylebone Limited | Administrative & support | 2025 |
| Kiss the Hippo Mercer Limited | Administrative & support | 2025 |
| Kiss the Hippo Pier Ltd | Administrative & support | 2023 |
| Kiss the Hippo Richmond Limited | Administrative & support | 2017 |
| Kiss the Hippo Roastery Limited | Administrative & support | 2017 |
| Kiss the Hippo SCP Limited | Administrative & support | 2026 |
| Kiss the Hippo Shoreditch Limited | Administrative & support | 2020 |
| Kiss the Hippo Soho Limited | Administrative & support | 2024 |
| Kite Refurbs Ltd | Construction | 2023 |
| Kiym Interiors Ltd | Professional & scientific | 2025 |
| KJV Limited | Construction | 2023 |
| KK & Sons Transportors Ltd | Transport & logistics | 2025 |
| KK Accounting Solutions Ltd | Administrative & support | 2017 |
| KK Eatery Ltd | Hospitality | 2025 |
| KK Educational Services Ltd | Administrative & support | 2025 |
| KK Scaffolding Ltd | Construction | 2025 |
| Kktt LLP | | 2018 |
| KL Cleaning Services Ltd | Administrative & support | 2019 |
| KL Contractors Ltd | Construction | 2019 |
| Klassic Nails Limited | Other services | 2022 |
| Kleena Technologies Ltd | Information & communication | 2025 |
| Klenam Consults Limited | Professional & scientific | 2012 |
| Klestro Properties Limited | Real estate | 2023 |
| Klicco Media Ltd | Professional & scientific | 2026 |
| KLT Business & Finance Ltd | Professional & scientific | 2019 |
| KLY Transport Ltd | Transport & logistics | 2026 |
| KM Logistic Services Ltd | Wholesale & retail | 2020 |
| KMK Construction Ltd | Construction | 2022 |
| Kmnp Ltd | Administrative & support | 2023 |
| KMW Care to Care Limited | Health & social care | 2015 |
| KN Infrastructure Consulting Limited | Information & communication | 2015 |
| KNF Team Limited Partnership | | 2016 |
| Knight Realty Limited | Real estate | 2019 |
| Knightsbridge Distribution Ltd | Administrative & support | 2011 |
| Knocking Opportunities Limited | Arts & recreation | 2016 |
| Knot BAD Joinery Limited | Information & communication | 2025 |
| Knots Furniture Limited | Manufacturing | 2014 |
| Ko'D Cosmetics Limited | Wholesale & retail | 2023 |
| KOA Foods Ltd | Wholesale & retail | 2025 |
| Kobari Ltd | Information & communication | 2015 |
| Kobee Company Limited | Other services | 2015 |
| Kobraa Ltd | Wholesale & retail | 2025 |
| KOC Bookkeeping and Consultancy Ltd | Professional & scientific | 2022 |
| KOC Maintenance Limited | Manufacturing | 2020 |
| Kockiri Properties Ltd | Real estate | 2019 |
| Koco Properties Ltd | Real estate | 2020 |
| Kodable Ltd | Information & communication | 2012 |
| Kofoza Holdings Ltd | Real estate | 2019 |
| Koipool Ltd | Information & communication | 2019 |
| Koksal Fish Bar Limited | Hospitality | 2024 |
| Kolapo Studios Ltd | Information & communication | 2020 |
| Kolina Commercial Ltd | Professional & scientific | 2018 |
| Komoproperty Ltd | Real estate | 2023 |
| Kompla Limited | Professional & scientific | 2026 |
| Konsey UK Events CIC | Other services | 2026 |
| Konsistent Consulting Limited | Information & communication | 2019 |
| Konsistent Labs Limited | Information & communication | 2024 |
| Konstruct Project Management Limited | Construction | 2009 |
| Konut 07 Limited | Hospitality | 2024 |
| Kore Ventures Ltd | Manufacturing | 2021 |
| Korels Cutting Room Ltd | Other services | 2026 |
| Korkmaz Consulting Ltd | Wholesale & retail | 2026 |
| Kortas Training UK. Ltd | Education | 2023 |
| Kosal Trade LP | | 2021 |
| Koshea Ltd | Health & social care | 2026 |
| Kosi ISE Limited | Public administration | 2024 |
| Koumea Properties Ltd | Real estate | 2023 |
| Kountouri Tutors Limited | Education | 2025 |