| BVA Planning Ltd | Professional & scientific | 2020 |
| BVC Rental Solutions Ltd | Administrative & support | 2021 |
| Bvisual Ltd | Information & communication | 1998 |
| Bvma Enterprises | Other services | 1999 |
| BVS Retail PVT Ltd | Wholesale & retail | 2025 |
| Bwanachana Enterprises Ltd | Real estate | 2012 |
| BX IT Limited | Other services | 2018 |
| BY Brinkworth Ltd | Agriculture & fishing | 2014 |
| BY Jennie Ltd | Professional & scientific | 2022 |
| By-Pass Farm Solar Limited | Energy | 2020 |
| Byclo Ltd | Wholesale & retail | 2025 |
| Byczok & Solomon Stores Limited | Wholesale & retail | 2016 |
| Byde Heating & Plumbing Limited | Construction | 2003 |
| Bymorayas Ltd | Hospitality | 2025 |
| Byron E Thompson Limited | Wholesale & retail | 2013 |
| Bytecoders Ltd | Information & communication | 2019 |
| Bytecraft Limited | Wholesale & retail | 2025 |
| Bytesizedword Limited | Information & communication | 2010 |
| Bythorn Properties Ltd | Real estate | 2021 |
| Bytlung Ltd | Construction | 2015 |
| Byvikistudio Ltd | Other services | 2025 |
| BZ Maritime Ltd | Administrative & support | 2024 |
| Bōken Watches Limited | Wholesale & retail | 2023 |
| C & C Properties Reading Limited | Real estate | 2020 |
| C & C Systems Limited | Manufacturing | 1996 |
| C & D Construction Property Maintenance Limited | Construction | 2026 |
| C & D Environment Limited | Real estate | 2025 |
| C & D Facilities & Grounds Maintenance Limited | Real estate | 2008 |
| C & D Grounds Maintenance Limited | Administrative & support | 2019 |
| C & S Energy Limited | Energy | 2021 |
| C & W Webber (Amners Farm) Limited | Agriculture & fishing | 2003 |
| C - Jaggi Construction Ltd | Construction | 2015 |
| C a R E Remembered Ltd | Administrative & support | 2018 |
| C a Waite Limited | Other services | 2014 |
| C and F Heating Ltd | Administrative & support | 2011 |
| C B Advisers Limited | Professional & scientific | 2017 |
| C B Electronics (Aldermaston) Ltd | Administrative & support | 2008 |
| C Brown Coaching & Consulting Ltd | Professional & scientific | 2019 |
| C C Sales Consultant Limited | Professional & scientific | 2015 |
| C Carter Photography Ltd | Professional & scientific | 2017 |
| C Contracting Ltd | Wholesale & retail | 2024 |
| C Court Management Company Limited | Households | 2014 |
| C E V Consultancy Limited | Administrative & support | 2014 |
| C F B T Education Services Limited | Education | 1992 |
| C F Limited | Professional & scientific | 1999 |
| C J Steel Ltd | Information & communication | 2013 |
| C Jackson Ltd | Information & communication | 2019 |
| C Lawrence Logistics Ltd | Transport & logistics | 2025 |
| C LIN Limited | Hospitality | 2016 |
| C Longstaff Ltd | Construction | 2023 |
| C N Brickwork Limited | Construction | 2016 |
| C Pepper Limited | Information & communication | 2026 |
| C R Barham Limited | Other services | 2003 |
| C&A Training Limited | Health & social care | 2016 |
| C&C Advisory Limited | Professional & scientific | 2017 |
| C&D Consulting Engineering Ltd | Administrative & support | 2007 |
| C&H Property Rentals Ltd | Real estate | 2024 |
| C-A Design Consultancy Ltd | Professional & scientific | 2018 |
| C-Loop Packaging UK Limited | Manufacturing | 2022 |
| C.A. Belcher & SON Limited | Wholesale & retail | 2015 |
| C.Appiah Ltd | Public administration | 2022 |
| C.B. Harper & Sons Limited | Real estate | 1963 |
| C.C. (Caversham) Management Company Limited | Extraterritorial | 1983 |
| C.D. Estates Management Limited | Households | 1990 |
| C.I.A Cleaning Services Ltd | Administrative & support | 2021 |
| C.Jones Productions Ltd | Professional & scientific | 2023 |
| C.M.C.Boiler Services Limited | Construction | 1971 |
| C8 Consulting Limited | Professional & scientific | 2003 |
| C8 Electrical Services Ltd | Construction | 2016 |
| CA Green Homes Limited | Real estate | 2023 |
| CA Limited | Information & communication | 1976 |
| CA Prop Co Ltd | Real estate | 2026 |
| CA Technology R&D Limited | Information & communication | 2010 |
| Caan Services Limited | Construction | 2021 |
| Caas Investments Limited | Real estate | 2023 |
| CAB Hire Direct Ltd | Administrative & support | 2019 |
| Cabestan Group Ltd. | Manufacturing | 2015 |
| Cabletel Herts and Beds Limited | Administrative & support | 1984 |
| Cabletel Surrey and Hampshire Limited | Extraterritorial | 1992 |
| Cabtime Ltd | Transport & logistics | 2018 |
| CAD Comrade Ltd | Professional & scientific | 2018 |
| Cadeaux (Caversham) Ltd | Wholesale & retail | 2025 |
| Cadence General Ltd | Other services | 2022 |
| Cadence Growth Solutions Limited | Professional & scientific | 2026 |
| Cadenza Investments Limited | Real estate | 2021 |
| Cadman Motor Company Limited | Wholesale & retail | 2009 |
| Cadogan House (Reading) RTM Company Limited | Households | 2026 |
| Caerus Change Limited | Professional & scientific | 2022 |
| Cafe Montague Ltd | Hospitality | 2026 |
| Cafe Tarifa Limited | Hospitality | 1988 |
| Cafe Xpress Three Ltd | Hospitality | 2007 |
| Cafe Yolk Ltd | Professional & scientific | 2024 |
| Caffe Vialottie Limited | Hospitality | 2022 |
| Cahill Davis Publishing Limited | Information & communication | 2020 |
| Cain Tree Ltd | Financial services | 2024 |
| Cake & Cream Ltd | Hospitality | 2018 |
| Cake and Beyond Limited | Manufacturing | 2025 |
| Cakes & More Limited | Wholesale & retail | 2024 |
| Cakes for ALL Occasions Limited | Manufacturing | 2015 |
| Cala (Payroll Preparation) Limited | Information & communication | 1979 |