| Convivium Event Services Ltd | Arts & recreation | 2024 |
| Conway QS Services Ltd | Professional & scientific | 2025 |
| Coolglass Glazing Enhancements Limited | Construction | 2022 |
| Coopers Property Maintenance Ltd | Professional & scientific | 2012 |
| Coops Rail Limited | Construction | 2017 |
| Core Survey & Inspect Ltd | Information & communication | 2020 |
| Cornerstone Connections Limited | Other services | 2001 |
| Corringham Properties Limited | Real estate | 2011 |
| COW Shack Limited | Manufacturing | 2020 |
| Cowries Group Ltd | Wholesale & retail | 2023 |
| Cox's Traditional Fish and Chips Limited | Hospitality | 2007 |
| CPA Business Consultants Limited | Professional & scientific | 2019 |
| CPA Limited | Professional & scientific | 2006 |
| CPR Commercials Export Limited | Wholesale & retail | 2016 |
| CPR Commercials Limited | Wholesale & retail | 2008 |
| CPY Acquisitions Ltd | Real estate | 2024 |
| Craggs PUB Holdings Ltd | Hospitality | 2025 |
| CRE8 Kitchens Bathrooms and Bedrooms Limited | Construction | 2018 |
| Creative Cuppa Ltd | Wholesale & retail | 2025 |
| Creative Kids Scunthorpe Ltd | Health & social care | 2022 |
| Crestview Residences Limited | Real estate | 2026 |
| Crooked Fish Bar Ltd | Hospitality | 2024 |
| Crowe Properties Ltd | Real estate | 2025 |
| Crystal Diamond I&Gm Ltd | Health & social care | 2019 |
| CS Tech Ltd | Wholesale & retail | 2024 |
| CSC Entertainment Ltd | Administrative & support | 2016 |
| CSG Physio Ltd | Public administration | 2011 |
| CT Safety Solutions Ltd | Administrative & support | 2026 |
| CTS Motorsport Ltd | Arts & recreation | 2016 |
| CTS Radio Systems Ltd. | Information & communication | 2002 |
| Cube Fireworks Ltd | Wholesale & retail | 2019 |
| Cubet Ltd | Administrative & support | 2013 |
| Cutting Couriers Ltd | Transport & logistics | 2020 |
| CWM Automation Limited | Manufacturing | 2006 |
| D & a Fenwick Limited | Agriculture & fishing | 2000 |
| D & a Road Freight Ltd | Transport & logistics | 2024 |
| D & T Taxis Gainsborough Ltd | Transport & logistics | 2012 |
| D and G Haulage Limited | Transport & logistics | 2015 |
| D Carlill Plumbing & Heating Limited | Construction | 2020 |
| D J Dent Ltd | Transport & logistics | 2025 |
| D K N Trading AS Just Lettings Limited | Real estate | 2008 |
| D L H Couriers Limited | Transport & logistics | 2021 |
| D S Motors Limited | Wholesale & retail | 2006 |
| D T C Productions Limited | Arts & recreation | 2003 |
| D Walker Brickwork and Building Services Limited | Construction | 2015 |
| D. Adams Plumbers Limited | Construction | 1965 |
| D.A. Yates Ltd | Construction | 2018 |
| D3 Risk Resilience Compliance Ltd | Professional & scientific | 2024 |
| Daisy Berkshire Ltd | Health & social care | 2022 |
| Daisy Pepper Limited | Wholesale & retail | 2025 |
| Dantani Assets Limited | Administrative & support | 2021 |
| Dantani Logistics Limited | Hospitality | 2015 |
| Danum Blinds Ltd | Wholesale & retail | 2018 |
| Danum Blinds Manufacturing Ltd | Manufacturing | 2026 |
| Danum Window Blinds Ltd | Construction | 2026 |
| Darbeck Limited | Professional & scientific | 1991 |
| Darley Associates Ltd | Professional & scientific | 2013 |
| Darley Homes Ltd | Construction | 2018 |
| Darley Land Ltd | Real estate | 2017 |
| Dart Bloodstock Polo Ltd | Agriculture & fishing | 2020 |
| Dart Livery Ltd | Agriculture & fishing | 2023 |
| Dart Polo Academy Ltd | Arts & recreation | 2024 |
| Dart Polo Club Ltd | Arts & recreation | 2024 |
| Dartom Ltd | Households | 2020 |
| Darwood Lettings Ltd | Real estate | 2025 |
| David Briggs Associates Limited | Health & social care | 2005 |
| DB Food and Wine Limited | Wholesale & retail | 2023 |
| Dean Robert Patrick Limited | Agriculture & fishing | 2003 |
| Deljo Consultancy Limited | Other services | 2022 |
| Deni’Z Unique World Ltd | Hospitality | 2024 |
| Depot Rail Limited | Manufacturing | 2004 |
| DESIGNS22U Ltd | Professional & scientific | 2014 |
| Desire Plumbing & Heating Ltd | Construction | 2023 |
| Destiny Abroad Private Limited | Professional & scientific | 2026 |
| Detaildigital Ltd | Information & communication | 2024 |
| Development Construction Ltd | Construction | 2021 |
| Devine Construction Management Ltd | Construction | 2025 |
| Dewicks Joinery and Building Services Limited | Construction | 2007 |
| DE’ Spectrum Limited | Financial services | 2025 |
| DG Accountants (Blyton) Ltd | Professional & scientific | 2022 |
| DH Aggregates Ltd | Water & waste | 2026 |
| DHW Electronics Limited | Wholesale & retail | 2011 |
| Diamond Cabs Ltd | Wholesale & retail | 2016 |
| Diamond Dealz Ltd | Wholesale & retail | 2024 |
| Diamond Power Specialty Limited | Manufacturing | 1913 |
| Diecast Model Centre Ltd | Wholesale & retail | 2022 |
| Digit Accounting Services Limited | Professional & scientific | 2016 |
| Digital Oracles Ltd | Information & communication | 2018 |
| DIN Sparkle Clean and Laundry Seevices Limited | Administrative & support | 2025 |
| Direct Hoist Ltd | Administrative & support | 2014 |
| Direct Property Rentals Limited | Real estate | 2018 |
| Dirty Laundry Group Ltd | Information & communication | 2026 |
| DJ Care and Service Limited | Health & social care | 2022 |
| DMR Consulting Services Ltd | Professional & scientific | 2019 |
| DN 888 Limited | Hospitality | 2022 |
| DN21 Scaffolding Limited | Construction | 2024 |
| DNC Software Ltd | Information & communication | 2010 |
| DOC Tall Medical Services Ltd | Health & social care | 2013 |
| Doctorrepairwithcare Ltd | Other services | 2017 |
| Dolbydene Enterprises Ltd | Other services | 2016 |