| Accounting and Taxation Advisory Firm Ltd | Derby | A rating |
| Accounting Crunchers Limited | London | A rating |
| Accounting for Sustainability | London | A rating |
| Accounting Office Software Ltd. | Neath | A rating |
| Accounting People Ltd | London | A rating |
| Accounting Solutions Manchester LLP | Salford | A rating |
| ACCOUNTING SQUARE LIMITED | LONDON | A rating |
| AccountingPreneur Ltd | Goodge Street | A rating |
| ACCOUNTINGWAYS LIMITED | Peterborough | A rating |
| Accountology Ltd | Manchester | A rating |
| ACCOUNTS & TAX INT LTD | London | A rating |
| Accounts and Tax Consultancy Ltd | Hayes | A rating |
| Accounts Computers Ltd | Sevenoaks | A rating |
| Accounts Direct (Accounting & Bookkeeping) Limited | Salford | A rating |
| ACCOUNTS HOUSE LTD | Upminster | A rating |
| Accountx Ltd | Oxford | A rating |
| Accredible Ltd | Ely | A rating |
| Accredo Support and Development Ltd | Leicester | A rating |
| Accrete Management Limited | London | A rating |
| Accrington Cricket & Tennis Club | Accrington | A rating |
| Accrington Surgical Instrument Suppliers Ltd | Accrington | A rating |
| Acctax (Online) Ltd | Manchester | A rating |
| AccTax Accountants Limited | Leicester | A rating |
| ACCTAX CONSULTANCY LIMITED | London | A rating |
| ACCTAX SERVICES LTD | Newcastle Upon Tyne | A rating |
| Accu Global Limited | Doncaster | A rating |
| Accu Limited | Huddersfield | A rating |
| Accu Technology UK Ltd | Oxford | A rating |
| Accu-Set Healthcare Ltd | Newark | A rating |
| Accubio Limited | Alva | A rating |
| Accubridge Consulting Group LTD | Nottingham | A rating |
| ACCUFINE LTD | NOTTINGHAM | A rating |
| Acculabs Diagnostics UK Ltd | Stockton on Tees | A rating |
| Acculearn Trading Limited T/A Cranbrook College | London | A rating |
| Acculegal Solicitors | Ilford | A rating |
| Accumont Ltd | London | A rating |
| Accunea Ltd | Kidderminster | A rating |
| Accupro Bookkeeping Ltd | Ashton Under Lyne | A rating |
| Accura Accountants Limited | Borehamwood | A rating |
| Accura Law Firm (UK) Limited | London | A rating |
| ACCURA RESOURCING LIMITED | London | A rating |
| AccuraCast Ltd | London | A rating |
| Accuracy UK Ltd | London | A rating |
| ACCURATE ACC LTD | Bedford | A rating |
| Accurate Accountant Co ltd | London | A rating |
| ACCURATE LASER & SKIN AESTHETICS LIMITED | London | A rating |
| Accuria Ltd | London | A rating |
| Accuride International LTD | Northampton | A rating |
| Accurite Industries Ltd | Ulverston | A rating |
| AccuRx Limited | London | A rating |
| Accutax Accountants Ltd | Surrey | A rating |
| Accuver EMEA Ltd. | Watford | A rating |
| ACD Environmental Ltd | Malmesbury | A rating |
| ACDCAT.IO limited | London | A rating |
| ACDOCO LIMITED | Bolton | A rating |
| ACE & Company UK Limited | London | A rating |
| Ace Accountants & Tax Consultants Ltd | ILFORD | A rating |
| ACE ACCOUNTS AND TAX LTD | MILTON KEYNES | A rating |
| Ace Adventure Limited | Forres | A rating |
| ACE ANALYTICS LIMITED | London | A rating |
| Ace Aquatec Ltd | Dundee | A rating |
| Ace Beauty Group Limited T/A Ace Beauty | Epping | A rating |
| Ace Care 4 U Limited | Nottingham | A rating |
| ACE CARGO SERVICE LTD | Feltham | A rating |
| ACE CARS & MINIBUSES LTD | Walsall | A rating |
| ACE CHILDRENS OCCUPATIONAL THERAPY LIMITED | Crondall | A rating |
| ACE CLEANERS AND REMOVALS LTD | Slough | A rating |
| ACE COMMUNITY SERVICES LIMITED | BANSTEAD | A rating |
| ACE CONSULTANTS LTD | Harrow | A rating |
| ACE CONTRACTOR 385 LIMITED | LONDON | A rating |
| Ace Engineering Solutions Ltd | London | A rating |
| ACE FLEET LIMITED T/A MOMO'S | London | A rating |
| Ace Global Services Limited | Leeds | A rating |
| ACE Group International Limited | Gerrards Cross | A rating |
| ACE HEALTHCARE SOLUTIONS LIMITED | Walsall | A rating |
| Ace Home Care Services Limited t/a Ace Homecare London | London | A rating |
| ACE Hotels Trading Ltd | London | A rating |
| Ace Infotech Solutions Ltd | Chadwell Heath | A rating |
| ACE IT Solutions Ltd | Orpington | A rating |
| ACE LABORATORIES LTD | Edgware | A rating |
| Ace Lifts Ltd | Deeside | A rating |
| ACE Medical Partnership | Birmingham | A rating |
| ACE MONEY TRANSFER LIMITED | Manchester | A rating |
| ACE OF FADES BARBER SHOP LTD | London | A rating |
| Ace of Hearts Creative Limited | London | A rating |
| Ace petroleum limited | Stoke on Trent | A rating |
| Ace Pilates Limited | London | A rating |
| Ace Pro Services Ltd | London | A rating |
| ACE PROPERTY FINDER LTD | LONDON | A rating |
| ACE REMOVALS LIMITED | London | A rating |
| Ace Rent A Van Ltd | London | A rating |
| Ace Software Solutions Ltd | London | A rating |
| ACE SPORTS MANAGEMENT LTD | BLACKBURN | A rating |
| Ace Stud Ltd | Newmarket | A rating |
| ACE SWEETS LIMITED T/A MAHARAJA SWEETS | Slough | A rating |
| Ace Tech Repairs Limited | Pudsey | A rating |
| Ace Technologies Limited | Newbury Park, Illford | A rating |
| Ace Test Limited | Birmingham | A rating |
| ACE THINKER LIMITED | Welling | A rating |
| ACE UK ENGINEERING CONSULTANTS LTD | Reading | A rating |
| Ace24 Healthcare Ltd | Colchester | A rating |
| ACEBRIDGE EDUCATION LTD | London | A rating |
| ACEDALE LIMITED | London | A rating |
| Acello Ltd | London | A rating |
| Acensys Ltd | London | A rating |
| ACEP Limited | London | A rating |
| ACEPAY LIMITED TRADING AS THE COTTAGE NURSING HOME | WALSALL | A rating |
| ACEPP UK LTD | London, | A rating |
| Aceprosoft Solutions Limited | London | A rating |
| ACER ACCOUNTANCY SERVICES LIMITED trading as Acumen+ | Rushden | A rating |
| ACER HEALTH CARE LTD | Birmingham | A rating |
| ACER International Limited | London | A rating |
| Acer Prime Law Ltd | Norwich | A rating |
| ACER PROPERTIES NORTH LTD | Preston | A rating |
| Acer Tree Investment Management LLP | London | A rating |
| Acer Trust | Oxford | A rating |
| Acer UK Limited | West Drayton | A rating |
| Acerinox (U.K.) LIMITED | West Midlands | A rating |
| Acero Construction Ltd | CHORLEY | A rating |
| Acerta24 Limited | Croydon | A rating |
| ACES Academies Trust | Huntingdon | A rating |
| Aces Haven Ltd | Staines | A rating |
| ACES JEWELLERS LIMITED | LISBURN | A rating |
| Aceso Global Health Consultants Limited | Greater London | A rating |
| Aceso Homecare | Sandbach | A rating |
| Acesure Ltd | London | A rating |
| Acetherix Healthcare Limited | LEICESTER | A rating |
| ACEVENTURES GROUP LTD | Willenhall | A rating |
| ACG Advisors Group (UK) Ltd | London | A rating |
| ACG Europe Ltd | Corby | A rating |
| ACG MEDICAL LIMITED | Chatteris | A rating |
| ACG Operations LTD | Birmingham | A rating |
| ACGAE LTD. | London | A rating |
| ACH Partners Limited | Perivale | A rating |
| Achelous Energy Ltd | Edenbridge | A rating |
| ACHERON CAPITAL LIMITED | LONDON | A rating |
| Achieve Pharma UK Limited | Henley-On-Thames | A rating |
| Achieve Teachers Ltd | London | A rating |
| Achieve together Limited | Twerton | A rating |
| Achieve UK Immigration Ltd | BIRMINGHAM | A rating |
| Achievement through Collaboration | Preston | A rating |
| Achievers Care Solutions Limited | Dartford | A rating |
| Achievers Solutions UK Ltd | London | A rating |
| ACHIEVING ABOVE AVERAGE LTD | London | A rating |
| Achieving for Children | Twickenham | A rating |
| Achilles Group Limited | Abindgon | A rating |
| Achuthan Arulananthan t/a Go Local | Grimsby | A rating |
| ACI Group Ltd | Cookham | A rating |
| ACI UK Learning Limited | Dartford | A rating |
| ACI Worldwide (EMEA) Limited | Brookwood | A rating |
| Aciana Limited | Worcester | A rating |
| ACIBADEM | London | A rating |
| Acier Global Ltd | London | A rating |
| Aciers UK Limited | Hounslow | A rating |
| Acierta UK LTD | london | A rating |
| acime UK Ltd | Manchester | A rating |
| Acinfo Limited | London | A rating |
| Acivico Group | Birmingham | A rating |
| ACIW LTD | Brierley Hill | A rating |
| ACJ ACCOUNTANTS LIMITED | Radlett | A rating |
| ACK Manufacturing Ltd | Bristol | A rating |
| Acker U.K. Ltd. | London | A rating |
| Acklam Medical Centre | Middlesbrough | A rating |
| Ackroyd House Limited | Rotherham | A rating |
| Ackroyd Legal (London) LLP | London | A rating |
| Ackroyd Lowrie Limited | London | A rating |
| Ackworth Cricket Club | Pontefract | A rating |
| Ackworth School | Pontefract | A rating |
| Ackworth Services Station Ltd | Dewsbury | A rating |
| ACL & Co | Surrey | A rating |
| ACL Education Solutions Ltd | London | A rating |
| ACL Homes Plus Ltd | Folkestone | A rating |
| ACL01 LIMITED | HEADCORN | A rating |
| ACLAS Technics Ltd | Livingston | A rating |
| ACLI (CHRISTIAN ASSOCIATION OF ITALIAN WORKERS) | LONDON | A rating |
| ACM Global Central Laboratory Limited | York | A rating |
| ACME CREDIT CONSULTANTS LIMITED | West Drayton | A rating |
| Acme People Limited | London | A rating |
| Acme Pharma Limited | Welwyn Garden City | A rating |
| ACME PROFESSIONALS LIMITED | HALESOWEN | A rating |
| ACME Shipping & Logistics | Southampton | A rating |
| Acme Vape Ltd | Preston | A rating |
| Acmefog Commerce Ltd | Manchester | A rating |
| ACMI UK LTD | WORCESTER | A rating |
| ACN ACCOUNTANTS | GRAYS | A rating |
| ACNielsen Company Limited | Oxford | A rating |
| ACO Building Company UK Ltd | Poole | A rating |
| ACO Technologies plc | Shefford | A rating |
| ACOCKS GREEN CAKE BOX LIMITED | Coventry | A rating |
| Acocks green dental practice | Acocks Green | A rating |
| Acocks View Limited | Birmingham | A rating |
| Acodia Ltd | London | A rating |
| Acolad UK Limited | London | A rating |
| ACOLYTE MANAGEMENT SERVICES LIMITED | BLACKBURN | A rating |
| ACOM Aviation | Witney | A rating |
| ACON CONSTRUCTION GROUP LIMITED | Hersham | A rating |
| Acora Limited | Burgess Hill | A rating |
| ACORD Corporation | London | A rating |
| ACORN (WATFORD) LTD | Watford | A rating |
| Acorn Bioenergy Limited | London | A rating |