| Keyways Adii Ltd | Manufacturing | 2017 |
| KG Soho Ltd | Wholesale & retail | 2020 |
| KGA Fitters Ltd | Construction | 2017 |
| KGM Consultancy Ltd | Professional & scientific | 2021 |
| Kgstar Barbers Ltd | Other services | 2026 |
| Khairo's Halal Food UK Limited | Hospitality | 2019 |
| Khalid London Ltd | Wholesale & retail | 2020 |
| Kham Khoon Thai Limited | Hospitality | 2025 |
| KHANAGE360 Ltd | Real estate | 2026 |
| Khanzadas Ltd | Information & communication | 2005 |
| Khorsand Properties Ltd | Real estate | 2026 |
| Ki-Ngs Barbers Male Grooming Ltd | Other services | 2016 |
| Kian Construction Ltd | Construction | 2022 |
| Kiani Gymnastics Academy Ltd | Arts & recreation | 2019 |
| Kids and Joints Ltd. | Health & social care | 2018 |
| Kids Beehive Ltd | Health & social care | 2022 |
| Kidz Choice 2 Ltd | Education | 2014 |
| Kifi Music Limited | Arts & recreation | 2013 |
| Kiings Building Contractors Ltd | Construction | 2020 |
| Kilcoyne & Scahill Motors UK Ltd | Wholesale & retail | 2018 |
| Kilfian Limited | Construction | 2006 |
| Kilgour Holdings Limited | Wholesale & retail | 2019 |
| Kilgour IP Ltd | Wholesale & retail | 2019 |
| Killingley Consulting Ltd | Professional & scientific | 2018 |
| Kima Estates Limited | Administrative & support | 2014 |
| Kimkatey Healthcare Services Limited | Health & social care | 2015 |
| Kinbond Limited | Real estate | 1997 |
| Kind Hands Care Agency Limited | Health & social care | 2022 |
| Kingdom Publishing Ltd | Manufacturing | 2021 |
| Kingfisher Assets Ltd | Construction | 2013 |
| Kingkongcrete Ltd | Construction | 2018 |
| Kingland Capital Partners Limited | Financial services | 2023 |
| Kings Law Chambers Limited | Professional & scientific | 2019 |
| Kingsbourne Windows & Doors Limited | Construction | 2006 |
| Kingschase Management Co. Limited | Households | 1985 |
| Kingshill Court Barnet (Freehold) Limited | Real estate | 1981 |
| Kingsley INS Brokers Ltd | Financial services | 2019 |
| Kingsly Estate Agents Limited | Real estate | 2024 |
| Kingsly Property Limited | Real estate | 2021 |
| Kingsmead Enterprises Ltd | Administrative & support | 2023 |
| Kingsmor Consulting Limited | Professional & scientific | 2018 |
| Kingswell Homes Ltd | Construction | 2017 |
| Kingsx Motors Limited | Wholesale & retail | 2003 |
| Kingwell Investments Limited | Real estate | 2002 |
| Kinson & Birch Ltd | Construction | 2015 |
| Kinte Consulting Ltd | Construction | 2018 |
| KIP Education Services Ltd | Education | 2019 |
| Kirishaash Limited | Wholesale & retail | 2009 |
| Kirkham Builders UK Ltd | Construction | 2025 |
| Kiron Surgery Limited | Real estate | 2005 |
| Kiss Community Adventure Limited | Administrative & support | 2012 |
| Kiss Contractors Ltd | Construction | 2026 |
| Kissinger Twins Studio Ltd | Professional & scientific | 2015 |
| Kittiwake Stays Ltd | Hospitality | 2026 |
| Kitty’S Coffees Ltd | Wholesale & retail | 2022 |
| Kivudesign Ltd | Arts & recreation | 2012 |
| KJ Retailer Limited | Information & communication | 2018 |
| Kjcc Limited | Other services | 2024 |
| Kjlg Properties Ltd | Real estate | 2024 |
| Kjsp Consulting Ltd | Professional & scientific | 2018 |
| KJW Property Services Ltd | Professional & scientific | 2023 |
| Kkpr Property Investments Ltd | Real estate | 2014 |
| Klam Ltd | Information & communication | 2025 |
| Klarity Risk Ltd | Professional & scientific | 2012 |
| Kleanfest Ltd | Administrative & support | 2025 |
| Kleanthous Consultants Limited | Professional & scientific | 2008 |
| Kleos Consulting Ltd | Information & communication | 2010 |
| KLK Imports & Exports Ltd | Wholesale & retail | 2023 |
| KLK London Consult Limited | Administrative & support | 2025 |
| KLK Property Holdings Limited | Real estate | 2026 |
| Klyno Ltd | Information & communication | 2025 |
| Kmah Group Ltd | Wholesale & retail | 2025 |
| KMG Project Management Limited | Administrative & support | 2008 |
| Kmgp Investments Limited | Real estate | 2022 |
| Kmpc London Limited | Professional & scientific | 2014 |
| KMS Lifetime Limited | Financial services | 2025 |
| Kmsz Ltd | Hospitality | 2020 |
| KN Civils Ltd | Energy | 2018 |
| Knight Hamilton Limited | Administrative & support | 2004 |
| Knight Land & Property Limited | Professional & scientific | 2012 |
| Knives for Chefs Ltd | Wholesale & retail | 2010 |
| KNN Construction Ltd | Construction | 2017 |
| Knocknaloman Ltd | Construction | 2022 |
| Know Thyself Coaching and Consulting Ltd | Professional & scientific | 2019 |
| Know Your Numbers Online Limited | Extraterritorial | 2024 |
| Knowing Meat Knowing YOU Harbourside Ltd | Hospitality | 2025 |
| Knowing Meat Knowing YOU Ltd | Hospitality | 2021 |
| Knwn Ltd | Health & social care | 2026 |
| Kodimari Holdings Limited | Financial services | 2019 |
| Kodr Ltd | Administrative & support | 2020 |
| Kojo RH Limited | Hospitality | 2019 |
| Koko Electrical Ltd | Construction | 2023 |
| Komags Ltd | Other services | 2017 |
| Komimor Limited | Real estate | 2019 |
| Komp Consulting Limited | Information & communication | 2016 |
| Konark Instruments & Control System Ltd. | Wholesale & retail | 2013 |
| Konderma Limited | Health & social care | 2024 |
| Konform Plant Limited | Administrative & support | 2022 |
| Konig Kitchens Ltd | Wholesale & retail | 2011 |
| Koohii & Co. Ltd | Hospitality | 2025 |