| NGC Management (UK) Limited | Altrincham | A rating |
| NGCP LIMITED | London | A rating |
| NGE Music ltd | Devizes | A rating |
| NGF EUROPE Limited | St Helens | A rating |
| NGG & More Limited | Southampton | A rating |
| NGK Spark Plugs (UK) Limited | Hemel Hempstead | A rating |
| NGM (MIDDX) LTD | Wembley | A rating |
| NGM Advertising LTD | London | A rating |
| NGOCLINH LIMITED | Reading | A rating |
| Ngopi International Limited | BIRMINGHAM | A rating |
| NGP Architecture Ltd | Edinburgh | A rating |
| NGP Utilities Ltd | Gateshead | A rating |
| NGPod Global Limited | Runcorn | A rating |
| NGR LIMITED | LEIGHTON BUZZARD | A rating |
| NGS Dumfries Ltd | Glasgow | A rating |
| NGS Salt Supplies Limited | Southampton | A rating |
| NGS Security Ltd | Faversham | A rating |
| NGT Road UK Ltd | Swadlincote | A rating |
| NH Foods U.K. Limited | London | A rating |
| NH Haydock Ltd T/A Rangoli Sankey Arms | Saint Helens | A rating |
| NH Investment & Securities Europe Ltd | London | A rating |
| NH Pharm Limited | Sutton Coldfield | A rating |
| NH TRADING (NW) LIMITED | Manchester | A rating |
| NHA CAREHOMES LTD | Torquay | A rating |
| NHA Enterprise Limited | London | A rating |
| NHC Technology Ltd | Denbigh | A rating |
| NHES Care Limited | Egham | A rating |
| NHG TIMBER LTD | Sanderstead | A rating |
| NHI RETAIL LTD | South Yorkshire | A rating |
| NHOA UK Limited | London | A rating |
| nhow London | London | A rating |
| NHP Companies Limited | Nelson | A rating |
| NHP Companies Limited TA Bluebird Care Burnley and Pendle | Nelson | A rating |
| NHRH LTD | Bagshot | A rating |
| NHRHLTD | Bagshot | A rating |
| NHS Ayrshire and Arran | Kilmarnock | A rating |
| NHS Birmingham and Solihull Integrated Care Board | Birmingham. | A rating |
| NHS Blood and Transplant | Barnsley | A rating |
| NHS Borders | Rushbank | A rating |
| NHS Bristol, North Somerset and South Gloucestershire Integrated Care Board | Bristol | A rating |
| NHS Business Services Authority | Newcastle Upon Tyne | A rating |
| NHS Central East Integrated Care Board | Ely | A rating |
| NHS Dorset | Dorchester | A rating |
| NHS Dumfries & Galloway | Dumfries | A rating |
| NHS Education For Scotland | Edinburgh | A rating |
| NHS England | Leeds | A rating |
| NHS Fife | GLENROTHES | A rating |
| NHS Forth Valley | Falkirk | A rating |
| NHS Frimley ICB | Aldershot | A rating |
| NHS Grampian | Aberdeen | A rating |
| NHS Greater Glasgow and Clyde | Glasgow | A rating |
| NHS Greater Manchester Integrated Care | Manchester | A rating |
| NHS Highland | Inverness | A rating |
| NHS Kent and Medway ICB | Maidstone | A rating |
| NHS Lanarkshire | Carluke | A rating |
| NHS Lancashire and South Cumbria Integrated Care Board | Preston | A rating |
| NHS Lothian | Edinburgh | A rating |
| NHS National Services Scotland | Edinburgh | A rating |
| NHS Norfolk and Suffolk Integrated Care Board | Norwich | A rating |
| NHS North Central London ICB | London | A rating |
| NHS North East and North Cumbria Integrated Care Board | Sunderland | A rating |
| NHS North East London Integrated Care Board (ICB) | London | A rating |
| NHS North West London Integrated Care Board | London | A rating |
| NHS Orkney | Kirkwall | A rating |
| NHS Property Services Ltd | London | A rating |
| NHS Resolution | London | A rating |
| NHS Shetland | Lerwick | A rating |
| NHS SOUTH EAST LONDON INTEGRATED CARE BOARD | London | A rating |
| NHS Tayside | Dundee | A rating |
| NHS Thames Valley Integrated Care Board | Oxford | A rating |
| NHS Wales Shared Services Partnership | Cardiff | A rating |
| NHS West and North London Integrated Care Board | London | A rating |
| NHS Western Isles | Stornoway | A rating |
| NHV Helicopters Limited | Aberdeen | A rating |
| NI Accountants | Dudley | A rating |
| NI Blood Transfusion Service | Belfast | A rating |
| NI ENGINEERING LTD | ballynahinch | A rating |
| NI FOODS LTD | Enniskillen | A rating |
| NI Human Rights Commission | Belfast | A rating |
| NI Hydraulic Pumps Ltd | COOKSTOWN | A rating |
| NI Trade Ltd T/A Burger King | Belfast | A rating |
| NI-LUX SOFTWARE LTD | Middlesex | A rating |
| NIA ENTERPRISE LIMITED | London | A rating |
| Niab | CAMBRIDGE | A rating |
| NIADORN LTD T/A AMAANI RESTAURANT | ASHTON-UNDER-LYNE | A rating |
| Niagara Energy Consultancy Ltd | Micheldever | A rating |
| NIAGRA BALTI LTD | Stoke-On-Trent | A rating |
| Niall Ferguson Limited | London | A rating |
| Niall McLaughlin Architects Ltd | London | A rating |
| NIAMOS LTD | MANCHESTER | A rating |
| Niantic Spatial UK Limited | London | A rating |
| Niarchos (London) Limited | London | A rating |
| Nibble Technology Limited | London | A rating |
| Nibbles UK Ltd t/a Londis | Barking | A rating |
| NIBC BANK NV | LONDON | A rating |
| Niblow Ltd | Chingford | A rating |
| NIBS SOLUTIONS LTD | Walsall | A rating |
| Nic Doodson Productions Limited | London | A rating |
| NIC ICE LIMITED | BARKING | A rating |
| NIC Instruments LTD | Folkestone | A rating |
| NICA LTD | Rainham | A rating |
| Nicco Fuel Ltd | Chailey, Lewes | A rating |
| Nicco Restaurant & Bar Limited | Derby | A rating |
| Nice Accounting & Management Limited | London | A rating |
| Nice and Solid LTD | London | A rating |
| NICE DAY NELSON LTD | Nelson | A rating |
| Nice Living Investment Ltd | Rugby | A rating |
| Nice Shirt Films Ltd | London | A rating |
| NICE Systems UK Limited | Southampton | A rating |
| Nice UK Ltd | Sutton in Ashfield | A rating |
| Niche & Bespoke Ltd | Birmingham | A rating |
| NICHE FOODS LIMITED | Leicester | A rating |
| Niche Innovations Ltd t/a Powerlase | Crawley | A rating |
| Niche Online Sales Group LTD | Bridgwater | A rating |
| Niche Projects London Limited | London | A rating |
| NICHE SKILLS LIMITED | Watford | A rating |
| Nichebox UK Limited | London | A rating |
| Nichesolutions GB Ltd | Northampton | A rating |
| Nichiei Limited | London | A rating |
| Nichino Europe Co. Ltd | Cambridge | A rating |
| Nicholas Associates Group Limited | Rotherham | A rating |
| Nicholas Hall & Company | Southend-on-Sea | A rating |
| Nicholas Jacob Architects LLP | Ipswich | A rating |
| Nicholas James Care Homes Ltd | Orpington | A rating |
| NICHOLAS KAREL LIMITED | PINNER | A rating |
| Nicholas Webb Architects PLC | Hertfordshire | A rating |
| Nicholas Wylde Goldsmith ltd | Bath | A rating |
| Nicholl Plaster Mouldings | Belfast | A rating |
| Nicholls News & Convenience Store Ltd | York | A rating |
| Nicholson & Co. Ltd | Malvern | A rating |
| NICHOLSON HOUSE LISBURN LTD | LISBURN | A rating |
| NICHOLSON NAIRN ARCHITECTS | Team Valley Trading Estate | A rating |
| Nicholson Search and Selection Ltd | London | A rating |
| Nicholson-Smith Limited | Cheltenham | A rating |
| NICHUANG (UK) LTD | London | A rating |
| Nici Hotels Limited | Bournemouth | A rating |
| Nick Building Contractors t/as NBC Group | Northfleet | A rating |
| Nick Cox Architects Ltd | Bicester | A rating |
| Nick Grace Management Ltd | Richmond | A rating |
| Nick Retail Limited | Chichester | A rating |
| Nickel Digital Asset Management Limited | London | A rating |
| NICKI SOUTER ASSOCIATES LIMITED | BY FORGANDENNY | A rating |
| NICKY LTD T/a ZH Convenience Store | Lancashire | A rating |
| Nicky News Limited | Romford | A rating |
| Nicky Richards Racing Ltd | Penrith | A rating |
| Nico Industrial Services UK | Southampton | A rating |
| Nico Properties (Sales & Lettings) Ltd | Leicester | A rating |
| NICOBRAND LIMITED | COLERAINE | A rating |
| Nicola Davidson T/A De Leon Physio | Arkley | A rating |
| Nicola Harding & Co | London | A rating |
| Nicolas James Building Limited | Southampton | A rating |
| Nicolaudie UK Limited | Brighton | A rating |
| Nicole Tailoring Boutique | Hornchurch | A rating |
| Nicoli Consulting Ltd | London | A rating |
| NICOLL ROAD NURSERY LIMITED | TWICKENHAM | A rating |
| NICOLSON CONTRACTS LTD | Glasgow | A rating |
| Nicomatic Ltd | London | A rating |
| Nicrone UK Limited | London | A rating |
| Nidderdale Group Practice | Harrogate | A rating |
| Niddrie Community Church | Edinburgh | A rating |
| Niddrie Community Shop | Edinburgh | A rating |
| Nidec Control Techniques Limited | Newtown | A rating |
| Nidhoggr Mead Co | Pocklington | A rating |
| NIDO LEGAL LTD | Birmingham | A rating |
| Nido Management UK Limited | London | A rating |
| Nido Montessori Nursery | London | A rating |
| NIE Networks | Belfast | A rating |
| Nielsen Media Research Ltd | London | A rating |
| Nielsens Accountants Limited | Ilford | A rating |
| NIEMANS CHEMISTS LIMITED | LONDON | A rating |
| Nieuw Limited | Tunbridge | A rating |
| NIF Investment Advisor Uk Ltd | London | A rating |
| NIF TELECOMS LTD | TILBURY | A rating |
| Nifco UK Limited | Stockton-on-Tees | A rating |
| Nifty Communications Ltd | Worcester | A rating |
| Niftylift Ltd | Milton Keynes | A rating |
| Nigekin Equestrian Ltd | Swindon | A rating |
| Nigel Frank International Ltd | Newcastle upon Tyne | A rating |
| Nigel Holland | WIDNES | A rating |
| Nigel Tinkler Racing LLP | Malton | A rating |
| Nigel Wright Consultancy Limited | Newcastle upon Tyne | A rating |
| NIGER DELTA YOUTH ASSOCIATION | SWANSEA | A rating |
| Nigeria High Commission London | London | A rating |
| NIGERIA LNG LIMITED | LONDON | A rating |
| Nigeria Nurses Charitable Association | Romford | A rating |
| NIGERIAN NATIONAL PETROLEUM CORPORATION | LONDON | A rating |
| Nigerian Ports Authority | London | A rating |
| NIGHT DREAM BEDS LIMITED | Dewsbury | A rating |
| NIGHT STAR DERRY PIZZA LTD | Londonderry | A rating |
| Nightcap employee service LTD | London | A rating |
| Nightingale Care Centre | Bucknall | A rating |
| Nightingale Care Support | Stourbridge | A rating |
| Nightingale Cottage Limited | Sandhurst | A rating |
| Nightingale Court Care Limited | Waterlooville | A rating |
| Nightingale Hammerson | London | A rating |
| Nightingale Health UK Limited | London | A rating |
| Nightingale Home Care (Scotland) Ltd | Falkirk | A rating |
| Nightingale Home Care Scotland Ltd | Falkirk | A rating |
| Nightingale House Hospice | Wrexham | A rating |
| Nightingale Medical Centre | Peterborough | A rating |