| Calauto Ltd | Wholesale & retail | 2026 |
| Calavera Ventures Limited | Professional & scientific | 2021 |
| Calbw Ltd | Transport & logistics | 2018 |
| Calco 101 Limited | Real estate | 2004 |
| Calco Group Limited | Administrative & support | 2017 |
| Calcom Limited | Construction | 2017 |
| Calculated Accountants Ltd | Professional & scientific | 2013 |
| Calcut Gardens Ltd | Professional & scientific | 2020 |
| Caldecote Property Investments Ltd | Real estate | 2026 |
| Caldecott Turkey Farms Limited | Agriculture & fishing | 1997 |
| Caldera Finance Limited | Financial services | 2025 |
| Calderdale Stewardship Hub Limited | Other services | 2026 |
| Calders Limited | Extraterritorial | 2008 |
| Calderwood Developments (Gainsborough) Limited | Administrative & support | 2019 |
| Calderwood Developments (Harworth) Limited | Construction | 2019 |
| Calderwood Property Investments (1) Limited | Construction | 2010 |
| Calderwood Property Investments (3) Limited | Construction | 2011 |
| Calderwood Property Investments (4) Limited | Construction | 2012 |
| Calderwood Property Investments (6) Limited | Construction | 2021 |
| Calderwood Property Investments Limited | Construction | 2000 |
| Caldmore Dera Limited | Hospitality | 2025 |
| Caldon Quay Residents Management Company Limited | Households | 2013 |
| Caldris Group Ltd | Wholesale & retail | 2026 |
| Caldwell House Consulting Ltd | Professional & scientific | 2005 |
| Caldwell Supermarket Ltd | Wholesale & retail | 2017 |
| Caledonian Leisure Sales Limited | Other services | 2006 |
| Caleno Limited | Administrative & support | 2026 |
| Caley Property Holdings Limited | Real estate | 2020 |
| Calgaz Ltd | Manufacturing | 2004 |
| Cali Events Ltd | Hospitality | 2025 |
| Caliba Group EOT Ltd | Professional & scientific | 2024 |
| Caliba Group Ltd | Professional & scientific | 2022 |
| Caliber Consultancy Limited | Financial services | 2023 |
| Caliber Housing Group Ltd | Hospitality | 2025 |
| Calibre Electrical and Mechanical Services Limited | Construction | 2016 |
| Calibre Logistical Services Limited | Construction | 2021 |
| Calibre Risk Management Limited | Information & communication | 2018 |
| Calibre Windows and Conservatories Limited | Construction | 1999 |
| Calico Theatre CIC | Information & communication | 2022 |
| Calima Properties Ltd | Real estate | 2024 |
| Caliserve Limited | Administrative & support | 2014 |
| Calistics Ltd | Wholesale & retail | 2026 |
| Calko Limited | Administrative & support | 2008 |
| Call for Company Limited | Health & social care | 2026 |
| Call Hill Ltd | Wholesale & retail | 2025 |
| Call ME Service Ltd | Administrative & support | 2024 |
| Call OUT Services Ltd | Energy | 2023 |
| Call-F Limited | Information & communication | 2025 |
| Callaghan Construction & Maintenance Ltd | Construction | 2015 |
| Callaghan Plant Ltd | Construction | 2014 |
| Callaid.Ai Ltd | Information & communication | 2026 |
| Callan Connect Group Limited | Financial services | 2024 |
| Callan Connect Limited | Construction | 2006 |
| Callan Connect Plant Limited | Construction | 2025 |
| Callan Properties Limited | Administrative & support | 2005 |
| Callary Projects Limited | Professional & scientific | 2025 |
| Callbird Ltd | Wholesale & retail | 2025 |
| Calledup Automations Ltd | Information & communication | 2025 |
| Calleva Investments Limited | Professional & scientific | 2017 |
| Callgas Heating and Plumbing Ltd | Construction | 2017 |
| Callh Ltd | Households | 2025 |
| Callidior Global Ltd | Wholesale & retail | 2022 |
| Calligraphy UK Limited | Other services | 2004 |
| Callow END Stores Ltd | Wholesale & retail | 2023 |
| Callow Hill Consulting Ltd | Professional & scientific | 2023 |
| Callow Hill Rock Ltd | Construction | 2018 |
| Callowside Management Company Limited | Real estate | 2021 |
| Callums Traffic Ltd | Construction | 2025 |
| Callure Well-Being & Fitness Ltd | Other services | 2025 |
| Calm & Clever Ltd | Manufacturing | 2025 |
| Calm Fire and Security Ltd | Administrative & support | 2023 |
| Calm Solu Limited | Real estate | 2023 |
| Calmer City Living Ltd | Real estate | 2018 |
| Calmer Estates Ltd | Real estate | 2024 |
| Calming Care Ltd | Health & social care | 2025 |
| Calow Design Limited | Professional & scientific | 2018 |
| Calow Testing Limited | Information & communication | 2015 |
| Calping Ltd | Manufacturing | 2026 |
| Calstar Limited | Wholesale & retail | 1987 |
| Calstock Estates Limited | Real estate | 2009 |
| Caltech Service Company Limited | Professional & scientific | 1997 |
| Calthorpe Arms Ltd | Hospitality | 2024 |
| Calthorpe Estates CF Nominee NO1 Limited | Real estate | 2011 |
| Calthorpe Estates CF Nominee NO2 Limited | Real estate | 2011 |
| Calthorpe Estates DS Nominee NO1 Limited | Real estate | 2011 |
| Calthorpe Estates DS Nominee NO2 Limited | Real estate | 2011 |
| Calthorpe Group Management Limited | Real estate | 2013 |
| Calthorpe Mansions Freehold Limited | Households | 1996 |
| Calthorpe Mansions Management Company Limited | Households | 1989 |
| Calthorpe Medical Limited | Financial services | 2025 |
| Calthorpe Properties Limited | Real estate | 2011 |
| Calthorpe Property Company Limited | Real estate | 1991 |
| Caltorc Limited | Wholesale & retail | 2024 |
| Calum Davies Limited | Construction | 2022 |
| Calumet Services Limited | Construction | 2008 |
| Calvary Chapel Birmingham Limited | Other services | 2004 |
| Calvary Evangelistic Ministry Birmingham Ltd | Other services | 2015 |
| Calvey & Co Contractors Ltd | Construction | 2023 |
| Calvic Care & Support Ltd | Education | 2023 |
| Calvic Electrical Soultions Ltd | Construction | 2012 |