| Coganscampers Ltd | Birmingham | 2024 |
| Cogas International Health Management Group Limited | West Midlands, England | 2024 |
| Cogent Design Limited | St Albans | 1999 |
| Cogent International Investments Ltd. | London | 2024 |
| Cogent Mechatronic Limited | Hunslet | 2017 |
| Cogent Paper Ltd | Edinburgh | 2026 |
| Cogent Seating Limited | Cowbridge | 2020 |
| Cogent Technology Limited | Ipswich | 1984 |
| Coggan Engineering Ltd | | 2003 |
| Coggin Sustainable Office Solutions Limited | Preston | 2017 |
| Coggins Audio Ltd. | Weston-Super-Mare | 2018 |
| Coggins Consulting & Coaching Ltd | Spalding | 2026 |
| Cogirls Limited | London | 2024 |
| Cogknox Limited | Cambridge | 2025 |
| Coglock Ltd | Northampton | 2023 |
| Cognex UK, Ltd | Birmingham | 1987 |
| Cognitive Bioscience UK Limited | London | 2022 |
| Cognitive Media Group Ltd | London | 2024 |
| Cognitive Robotics Ltd | London | 2026 |
| Cognoo Limited | Rickmansworth | 2018 |
| Cognoscenti Consulting Limited | London | 2004 |
| Cognosis Games Limited | Nottingham | 2011 |
| Cogri Engineering Limited | Huddersfield | 2006 |
| Cogsdill-Nuneaton, Limited | Nuneaton | 1961 |
| Cogswell & Harrison (Gunmakers) Limited | Hatfield | 1982 |
| Cohen & Bryan Interiors Ltd. | Dunmow | 2014 |
| Cohen Alloys Ltd. | | 1998 |
| Cohen Fabrications Ltd | Castleford | 2025 |
| Cohen Global Limited | London | 2020 |
| Cohen Limited | Chester | 2005 |
| Cohen Packaging Limited | | 1988 |
| Cohens Bakery Limited | London | 2012 |
| Coherence Ltd | Market Harborough | 2026 |
| Coherence Neuro Ltd | Cambridge | 2022 |
| Coherent Flux Limited | Leeds | 2025 |
| Coherent Research Limited | Kingston Upon Thames | 1989 |
| Coherent Scotland Limited | Glasgow | 1991 |
| Coherent Technologies Limited | Kingston Upon Thames | 1990 |
| Cohillson Limited | Manchester | 2012 |
| Cohline (U.K.) Limited | Canterbury | 1990 |
| Cohnab Limited | Northampton | 1998 |
| Cohno Limited | Henley-On-Thames | 2022 |
| Coho Alto Ltd | Llanfairpwllgwyngyll | 2021 |
| Coho Life Limited | Alnwick | 2018 |
| Coido Family Distillers Ltd | Romford | 2024 |
| Coil Maintenance Limited | Romsey | 2000 |
| Coil Processing Services Limited | Tipton | 1994 |
| Coil Products Limited | Walsall | 1959 |
| Coil Springs (1989) Limited | Manchester | 1989 |
| Coil Springs Direct Limited | Tipton | 2011 |
| Coil Sprung Beds Limited | Dewsbury | 2018 |
| Coil Tech UK Ltd | Deerhurst | 2003 |
| Coilco Limited | Cannock | 2009 |
| Coilcolor Limited | Manchester | 1992 |
| Coilcraft Europe Limited | Glasgow | 2000 |
| Coin LAB Ltd | Bolton | 2019 |
| Coin Solutions Limited | Manchester | 1999 |
| Coin Souvenir Ltd | Dartford | 2019 |
| Coincidentally Peoples Ltd | Woking | 2024 |
| Coiron Ltd | Livingston | 2015 |
| Coity Engineering and Site Services Ltd | Bridgend | 2010 |
| Cojarec International Sales Ltd | Gerrards Cross | 2015 |
| Cojo Interiorrss Limited | Hertford | 2019 |
| Cojocaru Aero Ltd | Cambridge | 2024 |
| Cojocia Engineering Limited | Bournemouth | 2014 |
| Coker and Sons Ltd | Rushden | 2024 |
| Coker Engineering Limited | Taunton | 1993 |
| Coker Exhibition Systems Limited | Hook | 2002 |
| Cokesimo Limited | Harrow | 2023 |
| Coko Group Limited | Warrington | 2020 |
| COL MC Engineering Ltd | Dungannon | 2010 |
| COL VAC Pumps Ltd | Craven Arms | 2011 |
| COL Welding & Fabrication Ltd | Leyland | 2026 |
| Col-Tec (Solutions) Limited | New Milton | 2000 |
| Colab Dental Technologies Limited | Oswestry | 2025 |
| Colab Surf Industries Ltd | Cornwall | 2024 |
| Colabs Innovations Ltd | Crewe | 2025 |
| Coladain Solutions Ltd | Louth | 2026 |
| Colado Cola Limited | London | 2025 |
| Colagaza Ltd | London | 2024 |
| Colair Electronics Limited | Colchester | 2018 |
| Colan Limited | Warwick | 1981 |
| Colbair Services Limited | Hertfordshire | 2003 |
| Colbax Fabrications Limited | Ashton Under Lyne | 2015 |
| Colbere Engineering Limited | Derbyshire | 1973 |
| Colbet Designs Limited | Ilkeston | 1989 |
| Colbier Brewery Ltd | Liverpool | 2023 |
| Colbourne Holdings Limited | Cramlington | 2023 |
| Colbridge Engineering Limited | Haywards Heath | 1979 |
| Colburn Ltd | Southsea | 2018 |
| Colby Co. Creatives Ltd | Haywards Heath | 2020 |
| Colchard UK Ltd | Halstead | 2022 |
| Colchester Bike Kitchen CIC | Colchester | 2024 |
| Colchester Brewery Ltd | Colchester | 2011 |
| Colchester Coffee Collective Limited | Colchester | 2025 |
| Colchester Engineering Solutions Ltd | Colchester | 2024 |
| Colchester Engineering Systems Limited | Colchester | 2006 |
| Colchester Fabrications Ltd | Colchester | 2018 |
| Colchester Fuel Injection Limited | Essex | 1976 |
| Colchester Lathe Co. Limited | Elland | 2014 |