| Concept Homecare Ltd | Tranent | A rating |
| Concept House Surgery | Bootle | A rating |
| Concept Housing Association CIC | Bradford | A rating |
| Concept Launch Partners Limited | Kettering | A rating |
| Concept Life Sciences, Integrated Discovery and Development Services Ltd. | High Peak | A rating |
| Concept Living Limited | Upper Basildon | A rating |
| Concept Projects Group Limited | Bromborough | A rating |
| Concept Systems Limited | Edinburgh | A rating |
| CONCEPT VC LIMITED | London | A rating |
| Concept Yachts Limited | Truro | A rating |
| Conceptdigital Ltd | London | A rating |
| Conception Design Associates | PRESTON | A rating |
| Conception X Limited | London | A rating |
| Conceptkicks Ltd | London | A rating |
| Concepto NIPT Limited | Watford | A rating |
| CONCEPTO SOLUTIONS LTD | LONDON | A rating |
| Concert (CGI) Limited | London | A rating |
| Concert Bio Ltd. | London | A rating |
| Concha Y Toro UK Ltd. | Wheatley | A rating |
| Concierge U Ltd | Stansted | A rating |
| Concilium Search Limited | London | A rating |
| Concirrus Ltd | London | A rating |
| Concord Resources Limited | London | A rating |
| Concord UK Group Services Limited | London | A rating |
| Concord UK Group Services Ltd | London | A rating |
| CONCORDE AUTO RECOVERY LTD | Crewe | A rating |
| Concorde Discount Wine Centre Ltd T/A Concorde Discount Wine Centre | Washington | A rating |
| Concorde Glass Limited | Mablethorpe | A rating |
| CONCORDE TYRES LTD | WOLVERHAMPTON | A rating |
| Concordia (UK) Ltd | Brighton | A rating |
| Concordia Global Finance Limited | London | A rating |
| Concordis International Trust | London | A rating |
| Concrete Batching Systems Limited | Armagh | A rating |
| Concrete Canvas Limited | Pontyclun | A rating |
| Concrete Capital Holdings Ltd | Birmingham | A rating |
| Concrete Construction United Limited | Rochester | A rating |
| CONCRETE DIRECT LIMITED | LONDON | A rating |
| Concrete Masters Ltd | Luton | A rating |
| Concrete Panel Systems Limited | NANTWICH | A rating |
| Concrete Rep. Ltd | London | A rating |
| Concrete Testing Solutions Limited | London | A rating |
| Concrete Wall Panels Ltd | Lockerbie | A rating |
| Concrete4Change Ltd | Nottingham | A rating |
| CONCRETED EDUCATION LTD | London | A rating |
| Concur Technologies (UK) Limited | Feltham | A rating |
| Concurrent Technologies Plc | Colchester | A rating |
| Condale Plastics Ltd | East Grinstead | A rating |
| Condimentz Ltd | Wokingham | A rating |
| Condition Environment Services Ltd | London | A rating |
| Conditioned Environment Mechanical Services Ltd | London | A rating |
| Condon Drew Associates Ltd. | Bristol | A rating |
| CONDOR DENT LIMITED | LONDON | A rating |
| Condover College Ltd | Shrewsbury | A rating |
| CONDUCE GROUP LIMITED | EDINBURGH | A rating |
| Conduct AI Ltd | London | A rating |
| Conductor Founders UK Limited | West Wickham | A rating |
| Conductor Marketing Limited | Wimbledon | A rating |
| Conductr Ltd | Manchester | A rating |
| Conduent Business Process Solutions Limited | London | A rating |
| Conduit Real Estate Ltd | London | A rating |
| Condukt Ltd | London | A rating |
| Conduktor UK Limited | London | A rating |
| CONE MARSHALL SERVICES (UK) LTD | London | A rating |
| CONECTERE CONSULTING LIMITED | ROMFORD | A rating |
| Conex Universal Limited | Kingswinford | A rating |
| Conexus Healthcare C.I.C | Wakefield | A rating |
| Confederation of Indian Industry (CII) | London | A rating |
| Conference Contacts Limited | Maidenhead | A rating |
| Conference Technologies UK Limited | Retford | A rating |
| ConferenceCast Ltd | London | A rating |
| Conferma Limited | Didsbury | A rating |
| Confex Limited | Cheltenham | A rating |
| CONFIDENT CONSTRUCTORS LTD | KENT | A rating |
| CONFIDENT HOME CARE LIMITED | WORKSOP | A rating |
| Confident Libra Ltd | London | A rating |
| CONFIDENT TAILORS LTD | BOLTON | A rating |
| Configure One Europe Ltd | London | A rating |
| Conflict Armament Research | London | A rating |
| Confluent Europe Ltd | London | A rating |
| Conformancex Ltd | Cambridgeshire | A rating |
| CONGA EUROPE LTD | London | A rating |
| Congenica LTD | Cambridge | A rating |
| Congregation of Jesus Charitable Trust | York | A rating |
| Congregation of Our Lady of Sion | London | A rating |
| Congregation of Our Lady of the Missions CIO | Harrow | A rating |
| Congregation of Our Lady, Canonesses of St Augustine CIO | London | A rating |
| Congregation of the Blessed Sacrament | Liverpool | A rating |
| Congregation Of The Daughters of the Holy Spirit CIO | Northampton | A rating |
| Congregation of the Dominican Sisters of Saint Catherin of Siena Newcastle, Natal | Bushey | A rating |
| Congregation of the Holy Spirit, British Province | Chester | A rating |
| Congregation of the Mission (The Vincentian Fathers) | London | A rating |
| Congregation of the Most Holy Redeemer | LONDON | A rating |
| Congregation of the Most Holy Redeemer - Redemptorists | Belfast | A rating |
| Congregation of the Passion of Jesus Christ | Glasgow | A rating |
| Congregation of the Sacred Heart of Jesus of Betharram | Solihull | A rating |
| Congregation of the Sacred Hearts of Jesus and Mary | London | A rating |
| Congregation Of The Sisters Of The Finding Of Jesus In The Temple | London | A rating |
| CONGREGATION OF THE SISTERS OF THE IMMACULATE HEART OF MARY, MOTHER OF CHRIST | Walsall | A rating |
| Congresbury Cricket Club | Bristol | A rating |
| Conifer Lodge | Leicester | A rating |
| Conifers Care Home | Thornton Cleveleys | A rating |
| Conifers Care Homes Ltd | Chester | A rating |
| Conifers Nursing Home | Great Wyrley | A rating |
| Conilon Ltd trading as Black Sheep Coffee | London | A rating |
| Coningsby Dental Practice | Coningsby | A rating |
| Conisbrough Cricket Club | Doncaster | A rating |
| Conjecture Ltd | London | A rating |
| Conjoint Export Services ( Near East ) Limited | Godalming | A rating |
| Conjure Ltd | London | A rating |
| Conker PJ Limited T/A Popley Pharmacy | Hampshire | A rating |
| CONLON CONSTRUCTION (NOTTINGHAM) LTD | NOTTINGHAM | A rating |
| CONMED | Swindon, Wilts | A rating |
| CONNAHS QUAY DENTAL PRACTICE LTD | Connah's Quay | A rating |
| Connate Limited | London | A rating |
| Connaught (UK) Limited | London | A rating |
| Connaught Dental House | Rayleigh | A rating |
| Connaught House Veterinary Group Ltd | Wolverhampton | A rating |
| Connaught Pubs Limited T/A Duke of Kendal | London | A rating |
| Connect 2 Flexicare Limited | Aylesbury | A rating |
| Connect 4 Energy Limited | London | A rating |
| Connect 44 Ltd | Bracknell | A rating |
| Connect Care Consultancy Ltd | Altrincham | A rating |
| Connect Care Services Ltd | Stockport | A rating |
| Connect Consultants Limited | Bristol | A rating |
| Connect Facilities and Services Limited | Leicester | A rating |
| Connect Healthcare Rotherham (CIC) | Rotherham | A rating |
| Connect In Cloud Ltd | Tilbury | A rating |
| Connect Into Care Limited | Willerby | A rating |
| Connect it Utility Services Ltd | Hedge End | A rating |
| Connect Learning Group Limited TA Canopy Children's Nursery | Hertfordshire | A rating |
| Connect Lettings and Management Ltd | London | A rating |
| Connect Managed Services (UK) Ltd | London | A rating |
| Connect Medical Solutions Limited | Milton Keynes | A rating |
| Connect Nursing LIMITED | London | A rating |
| Connect Property Solutions | Brierley Hill | A rating |
| CONNECT PVT LTD | London | A rating |
| Connect Software Solutions Limited | Nelson, Lancashire | A rating |
| Connect Talent CIO | Salford | A rating |
| Connect Three Solutions Ltd | Glasgow | A rating |
| CONNECT TRAVELS LTD | DARTFORD | A rating |
| Connect Ventures LLP | London | A rating |
| Connect Xtreme Ltd | Chatham | A rating |
| Connect: North Korea | New Malden | A rating |
| Connect2Law Limited | Richmond | A rating |
| CONNECT44 NEWCO LTD | Bracknell | A rating |
| Connectbike UK Ltd | London | A rating |
| CONNECTCOM SOLUTIONS LTD | London | A rating |
| CONNECTED CARE LTD | Birmingham | A rating |
| Connected Data Company Ltd | London | A rating |
| Connected Health Limited | Belfast | A rating |
| Connected IT Contract Limited | Manchester | A rating |
| Connected Kerb Limited | London | A rating |
| Connected Lives | London | A rating |
| Connected Places Catapult | London | A rating |
| Connected Security Group Ltd | Nelson | A rating |
| CONNECTED STARS LIMITED | Staines upon thames | A rating |
| Connected Together CIC | Northampton | A rating |
| Connected Voice | Newcastle upon Tyne | A rating |
| Connectia Education Ltd | Woking | A rating |
| CONNECTING CORE IT SOLUTIONS LIMITED | BROMLEY | A rating |
| Connecting Experts Ltd | London | A rating |
| Connecting Health Limited | London | A rating |
| Connection Crew | London | A rating |
| Connections 24hrs Ltd | Norwich, | A rating |
| Connections Care Limited | Leeds | A rating |
| Connections Healthcare Ltd | STEVENAGE | A rating |
| CONNECTIVE PHARMA LIMITED | SURREY | A rating |
| connective3 Ltd | Leeds | A rating |
| Connector Subsea Solutions (UK) Ltd | Wednesbury | A rating |
| CONNECTS FUTURE LTD | London | A rating |
| Connectum Ltd | London | A rating |
| ConnectWise Ltd | London | A rating |
| Conneely Drylining Ltd. | Stanstead | A rating |
| Connetix Ltd | LONDON | A rating |
| Connex Offsite Limited | Newry | A rating |
| Connex One Limited | Manchester | A rating |
| Connexas Holdings Limited | Northampton | A rating |
| Connexcel Ltd | Southampton | A rating |
| Connexin Ltd | Hull | A rating |
| Connexion Electrical Limited | London | A rating |
| Connexus Global EMEA Ltd | London | A rating |
| Connexxions Media & Marketing Ltd | Reading | A rating |
| Connick Tree Services Ltd | Reigate | A rating |
| Connies Special Authentic Ghanaian Restaurant Ltd | London | A rating |
| Connifers care Limited | London | A rating |
| Conning Asset Management Ltd | London | A rating |
| Conniston Care Limited | Nottingham | A rating |
| Conniston Care Limited | Epperstone | A rating |
| Connor Associates Limited | Preston | A rating |
| CONNOR CLARK & LUNN UK LIMITED | LONDON | A rating |
| Conochem Management Ltd | Haringey | A rating |
| Conochies Holdings LTD T/As Chaiiwala | Edinburgh | A rating |
| CONOCHIES LTD | Shetland | A rating |
| ConocoPhillips (U.K.) Holdings Limited | London | A rating |
| Conor J Walsh Golf Limited | Leatherhead | A rating |
| Conosco Ltd | London | A rating |
| Conovo Ltd | Slough | A rating |
| Conquer Hospitality Ltd | London | A rating |
| CONQUEST BUSINESS SOLUTIONS LTD | Altrincham | A rating |
| CONQUEST TECH SOLUTIONS LTD | England | A rating |