| Diligent Boardbooks Limited | London | A rating |
| Dimalnox UK Limited | London | A rating |
| Dimensional Fund Advisors Ltd | London | A rating |
| Dincer Logistics Limited | Waltham Cross | A rating |
| Dining Innovation UK Ltd | London | A rating |
| Dinosaur Merchant Bank Ltd. | London | A rating |
| Diona (UK) Limited | Chester | A rating |
| Diot Siaci Global Markets | London | A rating |
| Direct Link Worldwide Limited | Hayes | A rating |
| Direct Maintenance Aircraft Services UK Ltd | Gatwick | A rating |
| Direct Online Services Ltd | Quedgeley, Gloucester | A rating |
| Direct Wines Limited | Reading | A rating |
| Directflight T/A Airtask Group Ltd | Milton Keynes | A rating |
| Dirty Films Limited | London | A rating |
| Discover Financial Services (UK) Ltd | Farnborough | A rating |
| Discovery Communications Europe Limited | London | A rating |
| Discovery Education Europe Limited | Bath | A rating |
| DISHION OXFORD LTD | Oxford | A rating |
| Disperse.io LTD | London | A rating |
| DisplayLink (UK) Limited | Cambridge | A rating |
| Distell International Limited | East Kilbride | A rating |
| Distrelec Ltd | Manchester | A rating |
| Diversey Limited | Northampton | A rating |
| Dixa Limited | London | A rating |
| DKA GROUP UK LIMITED | London | A rating |
| DKMS Foundation | London | A rating |
| DLA Piper UK LLP | London | A rating |
| DLLNI Limited | Bangor | A rating |
| Dmg Events (UK) Limited | London | A rating |
| DMG Mori UK Limited | Coventry | A rating |
| DN Automotive VMS Ltd | Trowbridge | A rating |
| DN Capital (UK) LLP | London | A rating |
| DN Media Group Global AS | London | A rating |
| DNA Payments Limited | London | A rating |
| dnata Catering UK Limited | Manchester | A rating |
| DNB Bank ASA London Branch | London | A rating |
| DNB Carnegie Investment Bank AB UK Branch | London | A rating |
| DNV SERVICES UK LIMITED t/a DNV | London | A rating |
| DO and CO Event and Airline Catering Ltd. | Hounslow | A rating |
| Doble PowerTest Limited | Guildford | A rating |
| Docebo UK Limited | London | A rating |
| DOCEREE UK LIMITED | London | A rating |
| DOCOMO Europe Ltd. | London | A rating |
| DocuSign UK Limited | London | A rating |
| Dogma Group Ltd | London | A rating |
| Dogmates Ltd t/a Butternut Box | London | A rating |
| Dohler (UK) Limited | Milton Keynes | A rating |
| Dojima Sake Brewery UK & Co | Ely | A rating |
| DolarApp UK Ltd | London | A rating |
| Dolby Europe Limited | London | A rating |
| Dolce & Gabbana UK Limited | Worthing | A rating |
| Domestic & General Group Limited | Wimbledon | A rating |
| Dominion Bierrum Limited | Milton Keynes | A rating |
| Domino Data Lab Limited | London | A rating |
| DOMINO PRINTING SCIENCES PLC | BAR HILL | A rating |
| Domo Europe Limited | London | A rating |
| Domo Tactical Communications (DTC) Limited | Whiteley | A rating |
| Don & Low Limited | Forfar | A rating |
| Doncasters Limited | Leeds | A rating |
| Donnelley Financial Solutions UK Ltd | London | A rating |
| Doordash Technologies UK Ltd | London | A rating |
| Doosan Bobcat EMEA UK | Lancashire | A rating |
| DOOSAN DIGITAL INNOVATION EUROPE LIMITED | Paisley | A rating |
| Doosan Power Systems S.A. (UK branch) | Crawley | A rating |
| Doosan Water UK Ltd | Birmingham | A rating |
| Doppelmayr Cable Car UK Ltd | Birmingham | A rating |
| Dorco U.K. Limited | London | A rating |
| DORFNER ANZAPLAN UK LIMITED | London | A rating |
| Doris Engineering UK Limited | London | A rating |
| Dornbracht UK Ltd. | Coventry | A rating |
| Dornier Group UK Ltd | Glasgow | A rating |
| Doshi (London) Ltd | London | A rating |
| Doshi Accountants Limited | Croydon , London | A rating |
| Dotdigital EMEA Ltd | London | A rating |
| doTERRA Europe Ltd | Milton Keynes | A rating |
| DotSquares Ltd | Albourne | A rating |
| Double Negative Limited | London | A rating |
| DoubleVerify Ltd | London | A rating |
| Dover Fueling Solutions UK Ltd | Dundee | A rating |
| DOVER STREET MARKET INTERNATIONAL DSMI Ltd | London | A rating |
| Dow Chemical Company Limited | Cheadle | A rating |
| Dow Jones International Limited | London | A rating |
| Dowlais Group Headquarters Limited | London | A rating |
| Downhole Products Limited | Aberdeen | A rating |
| DOWNUNDER GEOSOLUTIONS (LONDON) PTY LIMITED | London | A rating |
| Doyle London Hotels Limited | London | A rating |
| DPS Games Ltd | Guildford | A rating |
| Dr Reddys Laboratories (UK) Limited | Cambridge | A rating |
| Dr. Reddy's Laboratories (EU) Ltd | Cambridge | A rating |
| DRA Projects Europe Limited | London | A rating |
| Dragados SA UK Branch | London | A rating |
| Drax Power Limited | Selby | A rating |
| Dream Games Publishing Limited | London | A rating |
| Dreamtel Hotel Limited | London | A rating |
| Dreamz Tech Solutions Pvt. Ltd | Watford | A rating |
| Dremio Limited | London | A rating |
| DRG UK Limited | Bury St Edmunds | A rating |
| Dril-Quip (Europe) Ltd | Aberdeen | A rating |
| Drillco Europe Limited | Leigh | A rating |
| Drilling Information Ltd | Stonehouse | A rating |
| Driscolls Genetics Limited | Maidstone | A rating |
| Droit Public Limited Company | London | A rating |
| DroneDeploy | London | A rating |
| Dropbox UK Online Limited | LONDON | A rating |
| DRP INTERNATIONAL (UK) LTD. | Berkshire | A rating |
| Druck Limited | Groby | A rating |
| Drug Development Solutions Ltd | Fordham | A rating |
| DRW Investments (UK) Ltd | London | A rating |
| DS Smith Business Services Limited | London | A rating |
| dscout UK LTD | Slough | A rating |
| DSM Nutritional Products (UK) Limited | Dalry | A rating |
| DSM Nutritional Products (UK) Limited | Heanor | A rating |
| DSP International UK Ltd | London | A rating |
| DSPACE Limited | Melbourn | A rating |
| DSRC UK Ltd | London | A rating |
| DSS International Ltd | London | A rating |
| DSS Sustainable Solutions UK Ltd | Upham | A rating |
| DSV Air & Sea Ltd | Harwich | A rating |
| DSV United Kingdom Ltd | Banbury | A rating |
| DT Industrial Group UK Limited | Milton Keynes | A rating |
| DTCC Europe Limited | London | A rating |
| DTEK INVESTMENTS LIMITED | London | A rating |
| Du Pont (UK) Limited | Stevenage | A rating |
| Dubai Equestrian Club UK Representative Office | Newmarket | A rating |
| Ducati UK Limited | Towcester | A rating |
| Duck Creek Technologies Limited | London | A rating |
| DUDE Hub Ltd | London | A rating |
| Duetto Research Limited | London | A rating |
| Duffel Technology Ltd | London | A rating |
| Duke Corporate Education Limited | London | A rating |
| Dun & Bradstreet Limited | London | A rating |
| Dunbia (UK) | Llanelli | A rating |
| Dunhills (Pontefract) Plc T/A HARIBO | Pontefract | A rating |
| Dunlop Aircraft Tyres Limited | Birmingham | A rating |
| Dunlop Golf Europe Ltd | Aldershot | A rating |
| dunnhumby Limited | London | A rating |
| Duolingo UK Limited | London | A rating |
| Duracell UK Ltd | Richmond | A rating |
| Durr Ltd | Warwick | A rating |
| Dustolex Limited | Littleborough | A rating |
| DVT Global (UK) Ltd | London | A rating |
| DWCC Ltd | Bristol | A rating |
| DWD Property and Planning Limited | London | A rating |
| DWF Group Limited | London | A rating |
| Dyaco UK Limited | Milton Keynes | A rating |
| DYDO DRINCO UK LTD | Ealing | A rating |
| Dye & Durham (UK) Limited | London | A rating |
| DYNAMATIC LIMITED UK | Swindon | A rating |
| Dynamatix Ltd | Milton Keynes | A rating |
| Dynamo Analytics Ltd | London | A rating |
| Dynamo Healthcare Training Ltd | Trevoarn, Hayle | A rating |
| DYNATA GLOBAL UK LTD | LONDON | A rating |
| Dynex Semiconductor Limited | Lincoln | A rating |
| Dynic(UK) Ltd | Cardiff | A rating |
| Dynolabs Asset Management Ltd | London | A rating |
| DynPro UK Ltd | Oxford | A rating |
| Dyson | Malmesbury | A rating |
| Dywidag Ltd | Bury | A rating |
| DZ Bank AG, Deutsche Zentral - Genossenschaftsbank | London | A rating |
| E- Event Platform Ltd | London | A rating |
| E-MUG ENGINEERING SERVICES LTD | London | A rating |
| E. & J. Gallo Winery | Uxbridge | A rating |
| E.CA Economics GmbH | London | A rating |
| e.l.f. Beauty UK Limited | Reading | A rating |
| E.ON UK plc | Nottingham | A rating |
| E9INE LIMITED | London | A rating |
| EagleBurgmann Industries UK LP | Warwick | A rating |
| EAI SYSTEMS LIMITED | London | A rating |
| EAK Management, UK Ltd | London | A rating |
| EAM Equestrian Limited | Evesham | A rating |
| Eappsys Limited | Brentford | A rating |
| Earnix UK Ltd | London | A rating |
| Earthood UK Limited | Sunbury-on-Thames | A rating |
| EAST COAST MANAGEMENT LIMITED | London | A rating |
| Eastdil Secured Ltd | London | A rating |
| Eastern Pacific Shipping (UK) Limited | London | A rating |
| EASY GO CONSULTING LIMITED | Manchester | A rating |
| easyHotel UK Ltd | London | A rating |
| EasyJet Airline Company Limited | Luton | A rating |
| EASYSHIP FS UK LIMITED | London | A rating |
| Easytransfer Limited | London | A rating |
| Eataly Retail UK Limited | London | A rating |
| Eaton Ltd | Slough | A rating |
| EATRON TECHNOLOGIES LIMITED | Warwick | A rating |
| Eaubrink Farm GMBH | Norfolk | A rating |
| Eba Interiors UK Limited | London | A rating |
| eBay (UK) Ltd | Richmond-upon-Thames | A rating |
| eBay Group Services (UK) Ltd | London | A rating |
| Ebebek UK Retail Services Ltd | London | A rating |
| EBI | London | A rating |
| Ebiquity Plc | London | A rating |
| Ebix Europe Limited | London | A rating |
| EBZ SysTec UK Ltd | Birmingham | A rating |
| ECARX Limited | London | A rating |
| Echo Geo Ltd | Buckingham | A rating |
| Echosec Systems UK Ltd | Cardiff | A rating |
| eClerx Ltd | London | A rating |
| ECMS EXPRESS (UK) LTD | Feltham | A rating |
| Ecolab Limited | Northwich | A rating |
| Ecolibrium Inc Ltd | London | A rating |