| Cairston Limited | Administrative & support | 2004 |
| Cake Kitchen by Tina Ltd | Manufacturing | 2025 |
| Cake Strings Ltd | Manufacturing | 2025 |
| Cakes by ANA Limited | Manufacturing | 2025 |
| Cakes N Platters Ltd | Hospitality | 2023 |
| Cakesetceterabynosen Ltd | Wholesale & retail | 2023 |
| Caketastic Limited | Hospitality | 2017 |
| Calaya Engineering Services UK Ltd | Other services | 2022 |
| Calcare Limited | Health & social care | 2025 |
| Calcutta Brasserie (Stony Stratford) Limited | Hospitality | 2019 |
| Caldecote Farm Trustee Limited | Real estate | 2022 |
| Caleb Abban | Health & social care | 2025 |
| Calfri Ltd | Administrative & support | 2025 |
| Cali Burritos Ltd | Hospitality | 2022 |
| Caliber Wealth Management Limited | Financial services | 2006 |
| Caljam Estates Ltd | Real estate | 2024 |
| Caljan Limited | Manufacturing | 1996 |
| Call Crystal Clear Ltd | Administrative & support | 2022 |
| Call Soso Ltd | Professional & scientific | 2024 |
| CALL4CARE Services Limited | Health & social care | 2015 |
| Callen Olive Limited | Wholesale & retail | 2021 |
| Callen Olive Podiatry Limited | Health & social care | 2016 |
| Calleo Consultants Ltd | Information & communication | 2016 |
| Callidus Properties Limited | Real estate | 2007 |
| Callums Removals and Transport Ltd | Transport & logistics | 2023 |
| Cally's Delicious Delights Ltd | Manufacturing | 2023 |
| Calm Palm Limited | Arts & recreation | 2024 |
| Calmar Consultancy Ltd | Professional & scientific | 2010 |
| Calsan Limited | Health & social care | 1988 |
| Caltec Production Solutions Limited | Other services | 2018 |
| Caltech Properties Limited | Real estate | 2000 |
| Caltonex Limited | Professional & scientific | 2015 |
| Calvary Place Ltd | Other services | 2025 |
| Calvinkmusic Limited | Other services | 2021 |
| Calyq Technologies Ltd | Information & communication | 2025 |
| Calyra Digital Ltd | Wholesale & retail | 2026 |
| Calyx Financial Planning Ltd | Financial services | 2025 |
| Cam-Xt Solutions Inc Ltd | Professional & scientific | 2020 |
| Camarinal Holdings Limited | Health & social care | 2017 |
| Cambed Properties Limited | Real estate | 2014 |
| Cambridge Bullion Company Limited | Manufacturing | 2026 |
| Cambridge Dental Hub Ltd | Health & social care | 2014 |
| Cambridge Education Services Ltd | Education | 2017 |
| Cambridge Strategy and Insight Ltd | Professional & scientific | 2017 |
| Camden BSF SPV Holdings Limited | Construction | 2010 |
| Camden BSF SPV Limited | Construction | 2010 |
| Camden School Projects Limited | Construction | 2010 |
| Camellia Systems Limited | Information & communication | 2011 |
| Cameron and Payne Associates Ltd | Professional & scientific | 2016 |
| Cameroon International Cultural Festival UK CIC | Hospitality | 2026 |
| Camfield Chapman Lowe Limited | Professional & scientific | 2007 |
| Camfridge Limited | Professional & scientific | 2003 |
| Camiiia Limited | Wholesale & retail | 2021 |
| Camilla Naprous Limited | Information & communication | 2013 |
| Campbell & Associates Development Ltd | Real estate | 2024 |
| Campbell Automotive MK Ltd | Wholesale & retail | 2021 |
| Campbell Heights Management Company Limited | Households | 2000 |
| Campbell Loomworks Limited | Manufacturing | 2025 |
| Campfire Education Trust | Education | 2011 |
| Camphill Contracts (Milton Keynes) Limited | Construction | 1986 |
| Camphill Insurance Agency Limited | Other services | 2005 |
| Camphill Milton Keynes Communities Limited | Health & social care | 1981 |
| Campions Management Limited | Households | 1986 |
| Campus Partners Group Ltd | Administrative & support | 2026 |
| CAN DO Services MK Ltd | Administrative & support | 2024 |
| Canaan Private Limited | Real estate | 2024 |
| Canada Rock Capital Limited | Financial services | 2025 |
| Canada Rock Limited | Professional & scientific | 2023 |
| Canal ST Coffee (Milton Keynes) Limited | Hospitality | 2022 |
| Canaryblue Limited | Information & communication | 2025 |
| Candice Cares Services Limited | Health & social care | 2026 |
| Candyland MK Limited | Health & social care | 2026 |
| Canine Diagnostic Innovations Ltd | Professional & scientific | 2020 |
| Cannatella & Colletti Limited | Administrative & support | 2019 |
| Cannoncourt Limited | Real estate | 1992 |
| Canonbury Products Limited | Wholesale & retail | 1983 |
| Canonbury Services Limited | Information & communication | 1999 |
| Canopus Professional Services (Europe) Limited | Information & communication | 2012 |
| Cantabrica Air Brokers Limited | Administrative & support | 1997 |
| Canterbury Gifts Ltd | Wholesale & retail | 2017 |
| Canvas Home Ltd | Wholesale & retail | 2014 |
| Canyon Security Ltd | Administrative & support | 2017 |
| Capa Hair Studio Limited | Other services | 2010 |
| Capa Hair Systems Ltd | Other services | 2024 |
| Capa Homes Ltd | Real estate | 2024 |
| Capability Development Support and Consultancy Limited | Professional & scientific | 2017 |
| Capadocia 2 Ltd | Hospitality | 2017 |
| Capadocia Olney Ltd | Hospitality | 2023 |
| Capalert Ltd | Other services | 2024 |
| Cape Logistics Ltd | Real estate | 2011 |
| CAPE82 Limited | Professional & scientific | 2024 |
| Capella Sports Ventures Ltd | Arts & recreation | 2016 |
| Capelltom Coatings Ltd | Construction | 2026 |
| Capercomplicity Limited | Information & communication | 2018 |
| Capex Investment UK Limited | Financial services | 2019 |
| Capital Care Investments Ltd | Real estate | 2013 |
| Capital Cutz Limited | Other services | 2025 |
| Capital Data Management Limited | Professional & scientific | 2018 |
| Capital Dimensions Limited | Professional & scientific | 2017 |
| Capital Growth Group Limited | Administrative & support | 2018 |