| Carrick Kids Ltd | Real estate | 2024 |
| Carrington-May Limited | Professional & scientific | 2004 |
| Carrowmore Investments Limited | Real estate | 2016 |
| Cars in MK Ltd | Wholesale & retail | 2023 |
| Carsington Sports & Leisure Limited | Arts & recreation | 1992 |
| Carso Limited | Transport & logistics | 2025 |
| Cartcuterie Ltd | Hospitality | 2024 |
| Carte Blanche Enterprises Ltd | Construction | 2017 |
| Carte Blanche Family Office Limited | Financial services | 2014 |
| Carter Jake Wealth Ltd | Information & communication | 2020 |
| Carters Cookery Ltd | Hospitality | 2026 |
| Carters Group Ltd | Other services | 2019 |
| Carters MK Ltd | Wholesale & retail | 2022 |
| Cartmel Advisory Services Limited | Professional & scientific | 2024 |
| Cartref Clyd Limited | Real estate | 2025 |
| Cartwright Clark Limited | Professional & scientific | 2006 |
| Cartz Ltd | Wholesale & retail | 2020 |
| Carvalho Homeware Ltd | Wholesale & retail | 2025 |
| Carvoyage Ltd | Wholesale & retail | 2026 |
| Carwyn Properties Ltd | Real estate | 2025 |
| Caryl Dexter Consultancy Limited | Administrative & support | 2018 |
| Carz MK Ltd | Wholesale & retail | 2024 |
| Cas-Sell CVC Limited | Wholesale & retail | 2022 |
| Casa 2 Casa Ltd | Real estate | 2009 |
| Casa DEL Padel MK Limited | Arts & recreation | 2024 |
| Casa Soleada Ltd | Wholesale & retail | 2021 |
| Casaluxe Estates Ltd | Households | 2024 |
| Cash Read Commercials Limited | Construction | 2014 |
| Cash Yang Ltd. | Information & communication | 2025 |
| Cashewselect Ltd | Other services | 2024 |
| Cashino Gaming (E&J) Limited | Professional & scientific | 1987 |
| Casino MK Limited | Arts & recreation | 2018 |
| Casinoonline.Com Limited | Information & communication | 2009 |
| Caskguard Limited | Financial services | 2025 |
| Caso Construction Ltd | Construction | 2012 |
| Caso Lettings Limited | Real estate | 2021 |
| Caspatcha Limited | Professional & scientific | 2024 |
| Casper and Co Ltd | Real estate | 2020 |
| Cassain Ltd | Professional & scientific | 2024 |
| Cassies Consulting Limited | Wholesale & retail | 2025 |
| Cassini Developments Limited | Construction | 2016 |
| Cassiusdel Mpsc Ltd | Transport & logistics | 2026 |
| Castech (U.K.) Limited | Professional & scientific | 1996 |
| Castel Property Services Ltd | Real estate | 2018 |
| Casterbridge Associates Limited | Construction | 2012 |
| Castle Chefs Ltd | Hospitality | 2026 |
| Castle Yard Limited | Real estate | 2023 |
| Castleacre Properties Limited | Real estate | 2023 |
| Castlehaven Investments Limited | Financial services | 2019 |
| Castlekeep Safety Ltd | Other services | 2024 |
| Castlethorpe Community Space CIC | Wholesale & retail | 2023 |
| Castlethorpe Village Shop Association Community Interest Company | Real estate | 2007 |
| Castor Solutions Ltd | Professional & scientific | 2019 |
| Casual Car Rental Ltd | Administrative & support | 2016 |
| Caswell Chiropractic Limited | Health & social care | 2019 |
| Cat-Blu Management Consulting Limited | Professional & scientific | 2017 |
| Catalyst Bicester Management Company Limited | Households | 2020 |
| Catalyst Health Solutions C.I.C. | Health & social care | 2021 |
| Catalyst Rating Limited | Administrative & support | 2025 |
| Catarsis Ltd | Transport & logistics | 2018 |
| Caterham Surgical Supplies Limited | Wholesale & retail | 1976 |
| Catermotive Ltd | Hospitality | 2020 |
| Cathesolo Healthcare Ltd | Extraterritorial | 2022 |
| Cats EYE Trading Limited | Hospitality | 2004 |
| Catterick Consultancy Services Limited | Professional & scientific | 2017 |
| Caty Fournier Translation Limited | Administrative & support | 2016 |
| CAU Catering Ltd | Wholesale & retail | 2025 |
| Caulder Financial Services Limited | Financial services | 2012 |
| Cauldwell Investments Ltd | Real estate | 2015 |
| Cauridor UK Limited | Information & communication | 2025 |
| Causeway & Co Ltd | Health & social care | 2025 |
| Cava Bien Limited | Other services | 2012 |
| Cavalier Smart Security Ltd | Extraterritorial | 2023 |
| Cavalry Creative Ltd | Professional & scientific | 2024 |
| Cavani MK Ltd | Wholesale & retail | 2022 |
| Cavendish Hold Ltd | Financial services | 2021 |
| Cavendish Investment Properties Ltd | Real estate | 2019 |
| Cavendish Medi Estates Ltd | Real estate | 2023 |
| Cavendish Properties UK Limited | Real estate | 1994 |
| Caviar House Airport Premium (UK) Limited | Wholesale & retail | 1984 |
| Cavorion Ltd | Wholesale & retail | 2026 |
| Cavox Limited | Information & communication | 2026 |
| Caxton Way (Dunstable) Management Limited | Households | 1990 |
| CB Primary Care Services Ltd | Health & social care | 2020 |
| Cbam-Uk Limited | Professional & scientific | 2024 |
| CBD Inc Ltd | Wholesale & retail | 2020 |
| CBF Group Limited | Financial services | 2020 |
| CBF Projects Ltd | Wholesale & retail | 2025 |
| CBK Management Limited | Professional & scientific | 2015 |
| Cbrf Enterprises Ltd | Hospitality | 2021 |
| CBS Trading Ltd | Manufacturing | 2013 |
| Cbsarcsafe UK Limited | Manufacturing | 2009 |
| CBW Surveyors Limited | Real estate | 2010 |
| CBZ Care Limited | Administrative & support | 2021 |
| CBZ Events Ltd | Administrative & support | 2025 |
| CBZ Studio Ltd | Information & communication | 2014 |
| CC Bathrooms Ltd | Construction | 2025 |
| CC Bosi Limited | Hospitality | 2019 |
| CC Bournemouth Limited | Construction | 2020 |
| CC Crown Birmingham Limited | Construction | 2021 |