| Cafe 100 Prazeres Ltd | Hospitality | 2023 |
| Cafe Henry Limited | Hospitality | 2014 |
| Cafe NAZ Limited | Hospitality | 2024 |
| Caffeine Free Ltd | Professional & scientific | 2025 |
| Cage Cricket Play C.I.C. | Arts & recreation | 2018 |
| Cainreno Ltd | Real estate | 2024 |
| Cakes by Lauren Ltd | Hospitality | 2024 |
| Caladan Properties Ltd | Real estate | 2015 |
| Calder Contemporary Fine Art Limited | Professional & scientific | 2024 |
| Calgoo 22 Ltd | Real estate | 2022 |
| Caliber Inbound Limited | Professional & scientific | 2026 |
| Calidad Installations Ltd | Construction | 2013 |
| Callidus Planning Ltd | Professional & scientific | 2020 |
| Callis Cafe Ltd | Hospitality | 2024 |
| Callixa UK Ltd | Professional & scientific | 2007 |
| Callsign Studios Ltd | Information & communication | 2023 |
| Calm Waters Worthing Ltd | Other services | 2025 |
| Calmco Ltd | Health & social care | 2019 |
| Calmrelief Ltd | Wholesale & retail | 2025 |
| Caltig Construction Southern Limited | Construction | 2017 |
| Cambell Warehouse Limited | Wholesale & retail | 2025 |
| Camber Electrical Ltd | Manufacturing | 2006 |
| Camber GAS Ltd | Construction | 2016 |
| Camber Home Improvements Limited | Construction | 2004 |
| Camberley Roofing Limited | Construction | 2023 |
| Cambers Edge Management Limited | Households | 2010 |
| Cambridge Medical Partners Limited | Health & social care | 2018 |
| Cambridge Solar & Electrical Limited | Construction | 2016 |
| Cambwick Ltd | Professional & scientific | 2024 |
| Cambwick Partners Ltd | Financial services | 2026 |
| Camcot Holdings Limited | Administrative & support | 2017 |
| Cameo Properties (Southern) Ltd | Real estate | 2020 |
| Camerondavis Limited | Arts & recreation | 2020 |
| Cami Holdings Ltd | Financial services | 2025 |
| Campbell Property Investments Limited | Real estate | 2006 |
| Camperlatte Ltd | Hospitality | 2024 |
| Campestre Properties Limited | Real estate | 2020 |
| Camrose Heating Ltd | Construction | 2022 |
| Cams Water Limited | Professional & scientific | 2024 |
| Canabeb Ltd | Financial services | 2020 |
| Canada House (Management Company) Limited | Real estate | 2002 |
| Cando Large Format Limited | Wholesale & retail | 2021 |
| Cannahealthuk Ltd | Public administration | 2025 |
| Canoe Lake Nursery Limited | Education | 2020 |
| Canute Property Limited | Construction | 2025 |
| Capdavies Ltd | Hospitality | 2020 |
| Capestream Limited | Administrative & support | 2011 |
| Capital HR Group Limited | Administrative & support | 2025 |
| Capstan House and Bosuns Court Residents Limited | Households | 2003 |
| Car Cleaning Supplies Ltd | Administrative & support | 2026 |
| Car Cosmetics Ltd | Wholesale & retail | 2013 |
| Car Perfections Ltd | Wholesale & retail | 2007 |
| Caravaggio Stamford Limited | Wholesale & retail | 2023 |
| Carbonedge Studio Ltd | Manufacturing | 2026 |
| CARCREDIT2GO.CO.UK Ltd | Other services | 2016 |
| Card Bros TCG Ltd | Wholesale & retail | 2026 |
| Card Solutions Limited | Administrative & support | 1997 |
| Cardinal Integrated Services Ltd | Construction | 2023 |
| Cardinals Executives Travel Ltd | Transport & logistics | 2024 |
| Care Aces Limited | Health & social care | 2024 |
| Care Action Recruitment Limited | Administrative & support | 2017 |
| Care Management Consultants Ltd | Professional & scientific | 2024 |
| Carepouch Services Limited | Financial services | 2024 |
| Carepro Training Limited | Education | 2025 |
| Cargo Same Day Ltd | Transport & logistics | 2023 |
| Caring at Home Your Way Ltd | Health & social care | 2021 |
| Caring for YOU Limited | Health & social care | 1998 |
| Caring Ladies Funeral Directors Limited | Other services | 1995 |
| Caring Lady Funeral Directors Limited | Other services | 2012 |
| Carl Ashley Electrical Services Limited | Construction | 2015 |
| Carlile Carpentry Ltd | Construction | 2023 |
| Carlton Court (Southsea) Management Company Limited | Households | 1988 |
| Carlton House Residents Association (Portsmouth) Limited | Households | 1978 |
| Carlton House Southsea RTM Company Ltd | Real estate | 2016 |
| Carlton Lodge Limited | Professional & scientific | 1969 |
| Carmar Consulting Limited | Administrative & support | 2015 |
| Carmen Investments Ltd | Real estate | 1988 |
| Carol Rents Rooms Limited | Real estate | 2015 |
| Caroline Neville Cosmetics Ltd | Wholesale & retail | 2023 |
| Carousel Nursery School (Hilsea) Limited | Administrative & support | 2002 |
| Carpe Diem Property Developments Ltd | Administrative & support | 2023 |
| Carr Priddle Management Limited | Real estate | 2002 |
| Carrad Engineering Ltd | Manufacturing | 2022 |
| Carrera (UK) Limited | Information & communication | 2010 |
| Carrick Scott Limited | Professional & scientific | 2015 |
| Carrin Construction & Development Ltd | Construction | 2026 |
| Carrington West Holdings Limited | Administrative & support | 2024 |
| Carrington West Limited | Administrative & support | 2010 |
| Carronade Walk, Hilsea (1,2,& 3) Management Company Limited | Households | 1984 |
| Carronade Walk, Hilsea (4 & 5) Management Company Limited | Hospitality | 1984 |
| Carrot Pharma Recruitment Ltd | Administrative & support | 2006 |
| CARS4SPARES Ltd | Wholesale & retail | 2026 |
| Carscom Limited | Wholesale & retail | 2021 |
| Carter Bond HQ Ltd | Professional & scientific | 2024 |
| Carter Home Rentals Limited | Real estate | 2019 |
| Casa 4 Developments Ltd | Construction | 2025 |
| Casa Diablo Tattoo Ltd | Arts & recreation | 2023 |
| Casa Mocha Ltd | Hospitality | 2020 |
| Casa Renovations Ltd | Construction | 2021 |
| Casa Sarda Limited | Hospitality | 2013 |