| Carlton Homes (Sawston) Limited | Construction | 2016 |
| Carlton Residential Developments Limited | Construction | 2013 |
| Carlton Supplements Ltd | Wholesale & retail | 2026 |
| Carluck Ltd | Health & social care | 2022 |
| Caro-Trans Ltd. | Transport & logistics | 2016 |
| Carol Davison Coaching Limited | Professional & scientific | 2015 |
| Carolina Business Limited | Information & communication | 2022 |
| Carolina Motors Limited | Wholesale & retail | 2024 |
| Caroline Briston Permanent Makeup Ltd | Other services | 2022 |
| Caroline Developments Holdings Limited | Real estate | 2010 |
| Caroline Foster Limited | Health & social care | 2015 |
| Caroline Lettings Limited | Real estate | 2018 |
| Caroline Wonnacott Limited | Health & social care | 2026 |
| Carology Customs Limited | Wholesale & retail | 2013 |
| Carolus Consulting Ltd | Professional & scientific | 2018 |
| Carolyns Digital Marketing Ltd | Professional & scientific | 2025 |
| Carp Fishing Lakes Ltd | Agriculture & fishing | 2020 |
| Carpe Diem Real Estates Limited | Real estate | 2020 |
| CARPENTER4YOU Ltd | Manufacturing | 2026 |
| Carpenters Mews MC Ltd | Households | 2021 |
| Carriage House Mews Flats Management Limited | Households | 1991 |
| Carrie BYE Consultancy Ltd | Professional & scientific | 2017 |
| Carrier Music Ltd | Wholesale & retail | 2021 |
| Carrilho Logistics Ltd | Transport & logistics | 2025 |
| Carroll & Taylor Limited | Health & social care | 2015 |
| Cars Direct Peterborough Limited | Wholesale & retail | 2019 |
| Cars Hub (EA) Ltd | Wholesale & retail | 2024 |
| Cars in Ltd | Wholesale & retail | 2024 |
| Carsin Automotive Ltd | Wholesale & retail | 2016 |
| Carson Holdings Ltd | Manufacturing | 2003 |
| Carson Office Environments Limited | Wholesale & retail | 1987 |
| Cartel Investments Limited | Real estate | 2013 |
| Cartell MOT and Service Ltd | Wholesale & retail | 2018 |
| Carter & Gregory Developments Limited | Construction | 2022 |
| Carter & Sons Property & Developments Ltd | Construction | 2025 |
| Carter Automotive Services Limited | Wholesale & retail | 2021 |
| Carter Electrical Ltd | Construction | 2012 |
| Carter Engineering Supplies Ltd. | Wholesale & retail | 2008 |
| Cartify Mart Ltd | Wholesale & retail | 2024 |
| Cartmel Court (Deeping) Management Company Limited | Households | 1986 |
| Carton-Pro Ltd | Manufacturing | 2010 |
| Carvetian Nominees Limited | Extraterritorial | 2015 |
| Carvoo UK Ltd | Wholesale & retail | 2026 |
| Carysfort Close Management Limited | Households | 2003 |
| Casa Amara Ltd | Wholesale & retail | 2025 |
| Casa Amata Limited | Transport & logistics | 2020 |
| Casa BAL Limited | Real estate | 2022 |
| Casa Mattoni Ltd | Hospitality | 2017 |
| Casa Tramonto Limited | Real estate | 2021 |
| Casa Wood Fired Pizza Ovens Limited | Wholesale & retail | 2018 |
| Casarva Limited | Manufacturing | 2006 |
| Casbon Building Services Limited | Construction | 2025 |
| Cashfarm Ltd | Wholesale & retail | 2024 |
| Cashflow Freedom Limited | Education | 2019 |
| Cashman Estates Ltd | Real estate | 2016 |
| Caspence Ltd | Agriculture & fishing | 2024 |
| Castaway Property Ltd | Real estate | 2023 |
| Castelle Care Solutions Ltd | Health & social care | 2019 |
| Castello Consulting Ltd | Professional & scientific | 2018 |
| Casting Defect Solutions Limited | Manufacturing | 2019 |
| Castlemaine Associates Ltd | Professional & scientific | 2016 |
| Castor & Ailsworth Village Hall Limited | Other services | 2016 |
| Castor Car Sales Limited | Wholesale & retail | 2025 |
| Castor Cars Ltd | Transport & logistics | 2024 |
| Castor Sound Limited | Information & communication | 2013 |
| Castorco Ltd | Professional & scientific | 2018 |
| Casworth Motors Ltd. | Wholesale & retail | 2007 |
| Cat & DOM Ltd | Transport & logistics | 2020 |
| Cataleya Properties Ltd | Real estate | 2022 |
| Catalin Panciuc Ltd | Transport & logistics | 2024 |
| Catchcarp Limited | Wholesale & retail | 2023 |
| Catchy Media Ltd | Information & communication | 2023 |
| Catenarian Arch Holding Limited | Financial services | 2016 |
| Cater and Merger Consult Ltd | Administrative & support | 2018 |
| Cater Link Services Ltd | Construction | 2020 |
| Cater Properties (Peterborough) Limited | Real estate | 2021 |
| Caterfair Ltd | Wholesale & retail | 2018 |
| Caterfix Limited | Wholesale & retail | 2002 |
| Catering Equipment Clearance Limited | Extraterritorial | 2012 |
| Catering Equipment Solutions (Peterborough) Ltd | Administrative & support | 2001 |
| Caterpillar Logistics (UK) Limited | Administrative & support | 2005 |
| Caterpillar Overseas Limited | Administrative & support | 2004 |
| Caterpillar Pension Trust Limited | Extraterritorial | 2000 |
| Caterpillar UK Engines Company Limited | Professional & scientific | 2005 |
| Caterpillar UK Group Limited | Extraterritorial | 2005 |
| Cath PE1 Ltd | Hospitality | 2026 |
| Catharsis Manufacturing Ltd | Manufacturing | 2022 |
| Cathedral Green Court Limited | Households | 1999 |
| Cathedral Square Ltd | Wholesale & retail | 2003 |
| Cathier Limited | Information & communication | 2019 |
| Catita Transport Ltd | Transport & logistics | 2018 |
| Catreats Limited | Wholesale & retail | 2021 |
| Cats Lane Property Development Limited | Construction | 2025 |
| Catterick (Cleveland Road) Residents Company Limited | Households | 2003 |
| Catterick (Hambleton) Residents Company Limited | Households | 2003 |
| Cattermoul Enterprises Ltd | Hospitality | 2025 |
| Caty Transport Ltd | Transport & logistics | 2022 |
| Caucasus Ltd | Real estate | 2022 |
| Cava Technical UK Ltd | Manufacturing | 2025 |
| Caves Driving School Limited | Education | 2017 |