| Within Design Limited | London | A rating |
| WITHIN LONDON LTD | London | A rating |
| Within People Ltd. | London | A rating |
| Within Reach Services Limited | Gloucester | A rating |
| WITHINS (BREIGHTMET) LIMITED | Bolton | A rating |
| WITHLOVE CARE LTD | Bradford | A rating |
| WithSecure Limited | Basingstoke | A rating |
| WITHTEK LTD | Southall | A rating |
| WithU Holdings Limited | Maidstone | A rating |
| WITLENS LTD | LEICESTER | A rating |
| Witley & Milford Medical Partnership | Witley | A rating |
| Witley Homes Construction Limited | Stourbridge | A rating |
| WITNEY FORECOURT LIMITED T/A BP | Witney | A rating |
| Witney Pizza Limited | Winey | A rating |
| Witt/Kieffer International Limited | London | A rating |
| WITTENSTEIN high integrity systems Ltd | Bristol | A rating |
| Witton Superstore Ltd | BIRMINGHAM | A rating |
| Wittur Ltd | Mold | A rating |
| Witty Kiddies Nurseries Ltd | Chatham | A rating |
| WIV Global Ltd T/A Winter in Venice | London | A rating |
| Wivels Field News Agent | Burgess Hill | A rating |
| Wivenhoe Town Cricket Club | Colchester | A rating |
| WIW Engineering Limited | Woking | A rating |
| WIX.COM (UK) LIMITED | London | A rating |
| Wixdek IT Limited | Romford | A rating |
| Wixot Studios Limited | London | A rating |
| Wiz Cloud Limited | London | A rating |
| Wiz Horse Ltd | Rochdale | A rating |
| Wiz Motors Limited | Luton | A rating |
| WIZ TECHNOLOGIES LTD | Hounslow | A rating |
| Wizard Video | London | A rating |
| Wize Services Limited | London | A rating |
| WizeCap Limited t/a Wizecap | London | A rating |
| WIZLANE LTD | Gerrards Cross | A rating |
| WIZWORLD LIMITED | Brentford | A rating |
| Wizz Air UK Limited | Luton | A rating |
| Wizzard Limited | London | A rating |
| WJ and R Parkinson | Preston | A rating |
| WJ Groundwater Limited | Kings Langley | A rating |
| WJ Nestle Limited | Southall | A rating |
| WJ North Limited | Newcastle under Lyme | A rating |
| WJ Partners Ltd | Birmingham | A rating |
| Wjb Management Limited | Wefherby | A rating |
| WJF Ramsay Ltd | Stranraer | A rating |
| WJR Developments UK Limited | London | A rating |
| WJX Beverage UK Limited | LONDON | A rating |
| WJX FOOD UK LTD | London | A rating |
| WK Ashby Limited | Ashby-de-la- Zouch | A rating |
| WK Restaurants Ltd | Coventry | A rating |
| WK Retail Group Ltd t/a Pepe's Piri Piri | Loughborough | A rating |
| WK Tech Expert and Consultancy ltd | Luton | A rating |
| WKMT Ltd. | London | A rating |
| WL Hillside Investment Limited | Birmingham | A rating |
| WL Vets Ltd | Rochdale | A rating |
| WL118 Ltd | Colchester | A rating |
| WLC CONSTRUCTION LTD | Burnham | A rating |
| WLF Innovations Ltd | Solihull | A rating |
| WLH Food Ltd | Durham | A rating |
| WLH Panda Ltd | SUNDERLAND | A rating |
| WLI (UK) Limited | Maidenhead | A rating |
| WLS LIMITED | London | A rating |
| WM & BALCKCOUNTRY CENTRAL HEATING LTD | Birmingham | A rating |
| WM BROWN (KINGSHURST) LIMITED | SOLIHULL | A rating |
| Wm Hamilton & Sons Ltd | Stonehouse | A rating |
| WM Morrison Supermarkets Limited | Bradford | A rating |
| WM PROPERTIES MANCHESTER LTD | Sale | A rating |
| WM Shipping Ltd (trading as Santova Logistics) | Tamworth | A rating |
| WM TYRES MOBILE SERVICES LTD | Birmingham | A rating |
| WMAS ENGINEERING LTD. | London | A rating |
| WMC Capital Ltd | London | A rating |
| WME Consultants Ltd | London | A rating |
| WMG Academy for Young Engineers | Coventry | A rating |
| WMG SERVICES LIMITED | LONDON | A rating |
| WMGS Europe Limited | London | A rating |
| WMH Systems Engineering Limited | Hayes | A rating |
| WMK HAULAGE LTD | Hounslow | A rating |
| WMS GLOBAL LTD | Edgware | A rating |
| WMS Group (UK) Ltd | Thame | A rating |
| WMS Recruitment | Wisbech | A rating |
| WN VTech Ltd | Bolton | A rating |
| WNA Gems and Jewels Ltd | London | A rating |
| WNB Trading Ltd | Hamilton | A rating |
| WNC UK Limited | Slough | A rating |
| WNGZ E3 LTD t/a WNGZ | London | A rating |
| WNGZ E5 LTD | LONDON | A rating |
| WNGZ HOLDINGS LTD | London | A rating |
| WNR Construction Services Ltd | Manchester | A rating |
| WNS Global Services (UK) | LONDON | A rating |
| WO GROUP LTD T/A WESTWOOD OPTICIANS | Oldham | A rating |
| Wobble Genomics Limited | Midlothian | A rating |
| WobbleWorks (UK) Limited | Milton Park | A rating |
| Woburn Autos Ltd | Leighton Buzzard | A rating |
| Woburn Cars Limited | Milton Keynes | A rating |
| WOBURN THAI LTD T/A WOBURN THAI | Milton Keynes | A rating |
| Wockhardt UK Limited | Wrexham | A rating |
| Woden Road Surgery | Wolverhampton | A rating |
| WODENSOFT LTD | London | A rating |
| Wok & Balti Limited T/A Mimosa | Camberley | A rating |
| WOK & ROLL CATERING LIMITED | Birmingham | A rating |
| Wok & Roll Ltd | Essex | A rating |
| Wok Express Wycombe Uk Ltd t/a Wok Express | High Wycombe | A rating |
| WOK KITCHEN (MANCHESTER) LTD | MANCHESTER | A rating |
| Wok Tech Limited | Willenhall | A rating |
| Wok to Walk | London | A rating |
| WOK-A-MOLEY | Luton, Beds | A rating |
| Woka ltd | Hertfordshire | A rating |
| WOKCOOKIN LIMITED | Rickmansworth | A rating |
| woke healthcare Ltd | barrow-in-furness | A rating |
| Wokhei Breath of the Wok Ltd | Slough | A rating |
| Woking And Horsell Cricket club | Woking | A rating |
| Woking And Sam Beare Hospice | Woking | A rating |
| Woking Foods and Wine Limited T/A Londis | Woking | A rating |
| Woking Football Club Limited | Woking | A rating |
| WOKING LOCAL PVT LTD | Woking | A rating |
| WOKING SPECSAVERS LIMITED | Surrey | A rating |
| Wokingham Borough Council | Wokingham | A rating |
| Wokingham Car Centre Ltd | Hook | A rating |
| WOKINGHAM CARS LTD | Berkshire | A rating |
| Wokingham Cricket Club | Wokingham | A rating |
| Wokingham Motors Limited | Wokingham | A rating |
| Wokingham Specsavers Limited | Wokingham | A rating |
| Wokingham Store Ltd | Reading | A rating |
| Woldingham School | Caterham | A rating |
| Wolds Veterinary Clinic Ltd | Grimsby | A rating |
| Wolf & Badger Ltd | London | A rating |
| Wolf Consulting & Management Ltd | London | A rating |
| Wolf Eyewear Limited | Leighton Buzzard | A rating |
| Wolf Ink Studios | Exeter | A rating |
| WOLF POWER SERVICES LIMITED | London | A rating |
| Wolf Systems Ltd | Coventry | A rating |
| WOLF WISDOM LTD | UXBRIDGE | A rating |
| WOLFE HOUSE LIMITED | Oxted | A rating |
| Wolfe Research (UK) Limited | London | A rating |
| Wolfe Vets Limited | London | A rating |
| Wolfestone Translation Limited | Swansea | A rating |
| Wolfeton Manor Healthcare Ltd | Dorchester | A rating |
| Wolffkran Limited | Sheffield | A rating |
| WOLFLAIR LIMITED | Coventry | A rating |
| Wolfox Ltd | Hove | A rating |
| Wolfram Research Europe Ltd | Long Hanborough | A rating |
| Wolfscastle Country Hotel | Haverfordwest | A rating |
| Wolfson Associates Limited | London | A rating |
| WOLFSON COLLEGE CAMBRIDGE | CAMBRIDGE | A rating |
| Wolfspeed Europe GmbH | Milton Keynes | A rating |
| Wollaston School | Wellingborough | A rating |
| Wollaton Cricket Club | Nottingham | A rating |
| Wolseley Medical Centre | Hull | A rating |
| WOLSELEY UK LIMITED | Warwick | A rating |
| Wolt Development UK Ltd | London | A rating |
| Wolters Kluwer (UK) Ltd | Surrey | A rating |
| Wolters Kluwer Financial Services UK Ltd | London | A rating |
| WOLTERS KLUWER HEALTH (MEDICAL RESEARCH) LTD | LONDON | A rating |
| WOLTERS KLUWER HOLDINGS (UK) LTD | KINGSTON UPON THAMES | A rating |
| Wolters Kluwer Tax and Accounting Ltd | London | A rating |
| WOLTON FOOD CO LIMITED | Wolverhampton | A rating |
| Wolverhampton Carpet & Flooring Limited | Wolverhampton | A rating |
| WOLVERHAMPTON CRICKET CLUB | WOLVERHAMPTON | A rating |
| Wolverhampton Girls' High School | Wolverhampton | A rating |
| Wolverhampton Road Surgery | Stafford | A rating |
| Wolverhampton Wanderers FC (1986) Ltd. | Wolverhampton | A rating |
| Wolverine Europe Limited | London | A rating |
| Wolverton Solutions Limited | Milton Keynes | A rating |
| Wolves News and Drinks | West Midlands | A rating |
| Wolves Wines Ltd | Wolverhampton | A rating |
| Wolveshill Consulting Ltd | London | A rating |
| WOLVEX LIMITED | Waterlooville | A rating |
| WOLVONEX LTD | London | A rating |
| WOMAD LTD | Box | A rating |
| Woman United | London | A rating |
| Womankind Worldwide | London | A rating |
| WOMBATS LONDON LTD. | London | A rating |
| Womble Bond Dickinson (UK) LLP | London | A rating |
| Wombourne Cricket Tennis And Bowling Club | Wolverhampton | A rating |
| Women for Women International UK | London | A rating |
| Women in Data Limited | Berrington Way | A rating |
| Women in Film and TV (UK) | London | A rating |
| Women in Tech SEO Ltd | London | A rating |
| Women's Best UK Ltd | London | A rating |
| Women's Equality Network Wales | Cardiff | A rating |
| Women's Pioneer Housing | London | A rating |
| Women's Professional Leagues Limited | LONDON | A rating |
| WONDA AFRICAN FOOD STORE LIMITED | Plymouth | A rating |
| Wonda Afro Caribbean Restaurant and Bakery LTD | Plymouth | A rating |
| WONDER CARE LTD | Coventry | A rating |
| Wonder Chicken Ltd. T/As Chicken Wonder | London | A rating |
| WONDER DOOR HEALER LTD | Feltham | A rating |
| WONDER FOUNDATION | London | A rating |
| Wonder Glass Ltd | London | A rating |
| Wonder Kids Nursery | West Drayton | A rating |
| Wonder London Limited | London | A rating |
| Wonder Works Limited | London | A rating |
| Wonderberry House Ltd | Farringdon | A rating |
| Wondercraft Tech Ltd | London | A rating |
| Wonderfield Group Limited | London | A rating |
| Wonderful Care Services Ltd | Peterborough | A rating |
| Wonderful Days Limited | Chatham | A rating |
| WONDERFUL GOSPEL MINISTRIES | Rowley Regis | A rating |
| Wonderfully Made Woman | Manchester | A rating |
| Wonderhatch Ltd | London | A rating |
| Wonderhood Limited | London | A rating |