| CT Fire Door Solutions Ltd | Worcester | 2025 |
| CT Fire Limited | Gillingham | 2026 |
| CT12174572 Limited | London | 2019 |
| CTD Defence Consultancy Ltd | Newark | 2025 |
| Ctfiregroup Ltd | Aylesford | 2020 |
| Cthorpe Healthcare Limited | Cradley Heath | 2023 |
| Cuirass Systems Ltd | Northwich | 2025 |
| Cultivate 2 Educate CIC | Wirral | 2025 |
| Cultural Action Hub CIC | Kingston Upon Thames | 2024 |
| Cultural Health Club CIC | London | 2020 |
| Cultural House Limited | London | 2024 |
| Culture Care @ Home Ltd | Nottingham | 2020 |
| Culture Care North CIC | Sunderland | 2022 |
| Cumbria Fire & Safety Training Limited | Penrith | 2020 |
| Cumming ODP Services Ltd | Worksop | 2022 |
| Cumulative Ltd | Birmingham | 2020 |
| Cura Chambers Ltd | Ashford | 2018 |
| Curabon Ltd | London | 2023 |
| Curamus Care Services Limited | Liverpool | 2025 |
| Curatum Social Care Consultancy Limited | Manchester | 2024 |
| Curran Legal Services Limited | Chichester | 2025 |
| Curtis Care Ltd | Barking | 2024 |
| Custodian Care Ltd | Salisbury | 2020 |
| Cutting Edge Content Limited | King'S Lynn | 2006 |
| CVM1 CIC | London | 2024 |
| Cvrt Parts Ltd | Poole | 2018 |
| CVS Enterprise Limited | Weston-Super-Mare | 2022 |
| CW Safety Systems Limited | Leigh-On-Sea | 2018 |
| Cwmni PUM Plwy Penllyn CYF | Bala | 2013 |
| CWN Clinical Ltd | Coatbridge | 2024 |
| Cymru Family Pathway Limited | Swansea | 2026 |
| Cyrstal Limited | London | 2018 |
| D & C Medical Ltd | Swindon | 2022 |
| D & G Fire Protection Limited | Motherwell | 2001 |
| D Ahkye Limited | Canterbury | 2018 |
| D and K Sendall Limited | Knebworth | 2018 |
| D B George Ltd | Lutterworth | 2026 |
| D B Mclarnon Fire Protection Agency Ltd | Belfast | 2015 |
| D Barnes Consulting Limited | Bonnyrigg | 2022 |
| D D BYE Limited | Grantham | 2020 |
| D H & S (Northamptonshire) Limited | Kettering | 2020 |
| D L Cheek Services Co Ltd | Barking | 2023 |
| D Lamoon Site Management Limited | Bromley | 2014 |
| D M K Installs Ltd | London | 2024 |
| D MAC Security Limited | Croydon | 2026 |
| D R Davis Fire Solutions Ltd | Hayes | 2020 |
| D S Fire Safety Ltd | Leven | 2021 |
| D Trinity Security Company Limited | London | 2022 |
| D&E Healthcare Recruitment Agency Ltd | Manchester | 2019 |
| D&G Living Ltd | Leicester | 2024 |
| D&M Lungu Limited | Bedford | 2018 |
| D&S Fire Limited | Middleton | 2013 |
| D-Wealth Care Limited | Cambridge | 2022 |
| D.A.O Care for Living Limited | Stevenage | 2024 |
| D.A.P.S.S Limited | York | 2023 |
| D.J. Fire Protection Services Ltd | Denby | 2009 |
| D.J.Mc Services Limited | Shrewsbury | 2025 |
| D3T Care Limited | Chelmsford | 2019 |
| DA Prism Ltd | Manchester | 2020 |
| Dabar Fire Prevention Limited | Sheffield | 2000 |
| Dabby's Personnel Limited | Sale | 2025 |
| Dabrio Recruitment Ltd | Cardiff | 2020 |
| DAC Quality & Safety Services Ltd | Alford | 2024 |
| Dada Wawili Limited | Romford | 2023 |
| Daddy PIG Kitchens Ltd | London | 2022 |
| Dadea Care Ltd | St. Ives | 2023 |
| Dadeon Health Care Limited | Hampshire | 2021 |
| DAE Safety Limited | Haslemere | 2026 |
| Dafar Ltd | London | 2024 |
| Dafd Ltd | Woking | 2020 |
| Dafidi Limited | Dartford | 2012 |
| DAG Safety Ltd | Yarm | 2022 |
| Dagger Solutions Ltd | Abergavenny | 2017 |
| Dahlhausen(Gb) Limited | Wimbledon Village | 2022 |
| Dahlia Moore Consultancy Ltd | London | 2024 |
| Daily Veda Ltd | London | 2020 |
| Dairaa (Smc-Private) Limited | Oldham | 2025 |
| Daisy & Iris Homecare Ltd | Southend-On-Sea | 2021 |
| Daisy Chain Care Team Ltd | Hitchin | 2017 |
| Daisy Cottages Ltd | Derby | 2020 |
| Daisy-Bell Care Limited | Birmingham | 2020 |
| Daisybk Limited | Craigavon | 2023 |
| DAL Strategy Limited | Ringwood | 2012 |
| Dalay Ltd | Hebburn | 2020 |
| Dalbeattie Fire Protection Limited | Motherwell | 2009 |
| Dalby Fire Limited | Birkenhead | 2019 |
| Dale Fire Protection Limited | Rochdale | 2006 |
| Dalex Health Ltd | Croydon | 2021 |
| Dalexia Homecare Ltd | Birmingham | 2025 |
| Dalmage Active Ltd | Woodford Green | 2019 |
| Damitee Ltd | Sittingbourne | 2022 |
| Dami’S Care Limited | Belfast | 2025 |
| Damrich Ltd | London | 2023 |
| Damy-Deel Limited | Manchester | 2023 |
| DAN Hall Fitness Ltd | Exeter | 2021 |
| Dance of Life Community CIC | Glasgow | 2025 |
| Dance to Inspire Community CIC | London | 2026 |
| DANDASERVICES25 Limited | Blackburn | 2025 |
| Daneshouse Community Partnership Ltd | Burnley | 2024 |
| Danger Close Training Ltd | Edinburgh | 2025 |