| Kanzen Consulting Limited | Professional & scientific | 2012 |
| Kapur Construction Consultancy Limited | Professional & scientific | 2015 |
| Karam Data Limited | Information & communication | 2022 |
| Karl Chaundy Design Ltd | Information & communication | 2021 |
| Karo Healthcare UK Ltd | Wholesale & retail | 2019 |
| Kashzarar Limited | Administrative & support | 2021 |
| Katam Technologies Ltd | Information & communication | 2018 |
| Kate Lovejoy Interiors Limited | Professional & scientific | 2021 |
| Katzner & Junker Rechtsanwalt Receiver Limited Partnership | | 2014 |
| Kayakojacko Limited | Arts & recreation | 2004 |
| Kayani Cuisine Group Limited | Hospitality | 2025 |
| Kbspartnership Europe Limited | Wholesale & retail | 2017 |
| KBW Enterprise Ltd | Administrative & support | 2021 |
| Kcai Trading Limited | Wholesale & retail | 2023 |
| KD Independent Assessments Ltd | Health & social care | 2023 |
| KDW International Advisors Ltd | Professional & scientific | 2024 |
| Keats House Consulting Limited | Other services | 2024 |
| Kebab Elite Foods Limited | Hospitality | 2023 |
| Kedbrooke Industries Limited | Wholesale & retail | 2005 |
| Keen & Eager Motor Engineers Limited | Wholesale & retail | 2006 |
| Kees Glass Limited | Construction | 2017 |
| KEG Health Ltd | Professional & scientific | 2019 |
| Kelebek Furniture UK Limited | Wholesale & retail | 2022 |
| Kelly Estates Limited | Real estate | 2025 |
| Kemp Taylor LLP | | 2007 |
| Kempton Carr (Maidenhead) Limited | Real estate | 2005 |
| Kendall Place Residents Management Company Limited | Households | 2004 |
| Kendra Energy Solutions Holdings Limited | Financial services | 2024 |
| Kendra Energy Solutions Limited | Professional & scientific | 1999 |
| Kendra EOT Trustee Limited | Administrative & support | 2024 |
| Kenmore Trading Limited | Administrative & support | 2018 |
| Kennel Close Management Ltd | Households | 2026 |
| Kennet Pharmacy Limited | Wholesale & retail | 1987 |
| Kent Education Partnership (Holdings) Limited | Financial services | 2005 |
| Kent Education Partnership Limited | Financial services | 2005 |
| Kepner-Tregoe Limited | Professional & scientific | 1966 |
| Kercel Construction Limited | Construction | 2022 |
| Kerns Retail Group Limited | Wholesale & retail | 2021 |
| Kerrigan Holdings Limited | Professional & scientific | 2018 |
| Kerrydan Limited | Professional & scientific | 2006 |
| Kesavan Consulting Limited | Information & communication | 2012 |
| Ketton Cement Limited | Professional & scientific | 1972 |
| Kevrich Ltd | Wholesale & retail | 2025 |
| KEW Design and Consulting Ltd | Professional & scientific | 2023 |
| Key Choice Builders Limited | Construction | 2014 |
| Key Principles Limited | Information & communication | 2023 |
| KEY2STORAGE Limited | Information & communication | 2007 |
| KEY33 Ltd | Professional & scientific | 2022 |
| Keyersbridge Limited | Arts & recreation | 2011 |
| KEYS2GO & Autocare Ltd | Wholesale & retail | 2020 |
| Keystone Contracting Services Ltd | Professional & scientific | 2024 |
| Keytech Networks Ltd | Information & communication | 2015 |
| KG Copy Limited | Professional & scientific | 2022 |
| Khalil Telecomm Ltd | Information & communication | 2023 |
| Khalsa Brothers Ltd | Wholesale & retail | 2023 |
| Khanova Private Limited | Wholesale & retail | 2026 |
| Khas Consulting Ltd | Wholesale & retail | 2017 |
| Kiche Consulting Ltd | Arts & recreation | 2016 |
| Kickboxing GB Limited | Arts & recreation | 2015 |
| Kiddykare Limited | Administrative & support | 2008 |
| Kids Coding Academy Limited | Information & communication | 2019 |
| Kids Gym Limited | Arts & recreation | 2004 |
| Kids Universe Ltd | Health & social care | 2021 |
| Kies Home Ltd | Construction | 2021 |
| Kilmount Construction Ltd | Construction | 2020 |
| KIM Pettigrew Limited | Professional & scientific | 2017 |
| Kimbers Builds Limited | Real estate | 2024 |
| Kindling Group Ltd | Professional & scientific | 2021 |
| Kindred Advisory Ltd | Professional & scientific | 2024 |
| Kinematics Ltd | Information & communication | 1997 |
| King Builders & Decorators Limited | Construction | 2002 |
| Kingcome Court Management Limited | Households | 1989 |
| Kingdom Come Temple Ltd | Other services | 2018 |
| Kingfishers Residents (Maidenhead) Limited | Households | 1984 |
| Kings Lettings Limited | Real estate | 1990 |
| Kings Plumbing & Heating Limited | Construction | 2002 |
| Kingsacre Homes Limited | Construction | 2004 |
| Kingsland Investments Limited | Real estate | 2014 |
| Kingsley Construction (Southern) Limited | Construction | 2002 |
| Kingsley Plant Limited | Real estate | 2010 |
| Kingsley Properties (Southern) Limited | Real estate | 2016 |
| Kingston Minerals Limited | Professional & scientific | 1912 |
| Kinisi Productions Limited | Information & communication | 2019 |
| KIO Method Ltd | Administrative & support | 2025 |
| Kiperin Limited | Wholesale & retail | 2024 |
| Kirkan Wind Farm Limited | Energy | 2014 |
| Kirkwood Personal Estate Agents Limited | Real estate | 2013 |
| Kisj Limited | Real estate | 2022 |
| Kiss Development Services Ltd | Information & communication | 2024 |
| Kitchen Restyle Limited | Construction | 2015 |
| Kitchenism Ltd | Wholesale & retail | 2018 |
| Kite Designs Ltd | Wholesale & retail | 2019 |
| Kitson Way Limited | Real estate | 2025 |
| Kiyuri Limited | Administrative & support | 2015 |
| KJP Consulting Services Ltd | Public administration | 2019 |
| KK & P Limited | Wholesale & retail | 2022 |
| KKI Grunenthal UK Holdco Ltd | Financial services | 2022 |
| KL Couriers Limited | Transport & logistics | 2018 |
| KL Electronic Solutions Limited | Professional & scientific | 2017 |
| Klaus DI Ltd | Construction | 2024 |