| NH Adaptive Ltd | Professional & scientific | 2026 |
| NH Estates Ltd | Construction | 2021 |
| NH Finance Holdings Ltd | Financial services | 2021 |
| Nhat HUY Ltd | Other services | 2021 |
| Nhembocare Limited | Health & social care | 2023 |
| NHM Advisory Limited | Financial services | 2020 |
| NI Fast Food Ltd | Hospitality | 2025 |
| NI Holidays Limited | Hospitality | 2021 |
| NI Management Services Limited | Administrative & support | 2019 |
| Ni's Tasty House Limited | Hospitality | 2020 |
| NI7E Limited | Information & communication | 2026 |
| Niamh Isobel Limited | Hospitality | 2014 |
| Niar Properties Ltd | Real estate | 2024 |
| Niaz Bakers Limited | Manufacturing | 2025 |
| Niazi Holdings Ltd | Real estate | 2023 |
| Nibnibs Ltd | Manufacturing | 2009 |
| NIC FM Services Group Limited | Administrative & support | 2021 |
| NIC Franchising Limited | Administrative & support | 2012 |
| NIC Group Investments Limited | Construction | 2020 |
| NIC Local Limited | Other services | 2022 |
| NIC Orsi Ltd | Professional & scientific | 2021 |
| NIC Property Services LLP | | 2020 |
| NIC Services Group (UK) Limited | Administrative & support | 2010 |
| NIC Services Group Limited | Administrative & support | 2004 |
| Nice Consulting Limited | Health & social care | 2010 |
| Nice One Cleaning Services Ltd | Manufacturing | 2024 |
| Nicemil Ltd | Health & social care | 2016 |
| Niche Glass Ltd | Manufacturing | 2017 |
| Niche Nail Network Limited | Administrative & support | 2022 |
| Nichitel Logistics Ltd | Transport & logistics | 2023 |
| Nichoboss Property Ltd | Real estate | 2026 |
| Nicholas & Nicholas Limited | Professional & scientific | 2007 |
| Nicholas Collins Limited | Professional & scientific | 2018 |
| Nicholas James (UK) Limited | Manufacturing | 1982 |
| Nicholas Young Limited | Information & communication | 2012 |
| Nicholmes Ltd | Real estate | 2022 |
| Nichols Dental Reporting Ltd | Health & social care | 2020 |
| Nicholson Media Group Ltd | Information & communication | 2026 |
| Nicholson Property Holdings Ltd | Real estate | 2022 |
| Nicholsons 24/7 Recovery Ltd | Transport & logistics | 2026 |
| Nicholsons Silencers (1988) Limited | Professional & scientific | 1919 |
| Nick Beaumont Builders Ltd | Construction | 2026 |
| Nick Brown Architects Ltd | Professional & scientific | 2011 |
| Nick Fitzpatrick Limited | Arts & recreation | 2013 |
| Nick Gott Welding Solutions Ltd | Extraterritorial | 2024 |
| Nick Halliday Limited | Professional & scientific | 2012 |
| Nick Place Limited | Construction | 2013 |
| Nick Quayle Motion Design Limited | Professional & scientific | 2021 |
| Nick White Forensic Accounting Limited | Professional & scientific | 2019 |
| Nickelstar Limited | Professional & scientific | 2014 |
| Nicki Pratt Limited | Professional & scientific | 2024 |
| Nicklett Property Ltd | Hospitality | 2025 |
| Nicky's Hair Boutique Ltd | Other services | 2019 |
| Nickyb's Wardrobe Ltd | Wholesale & retail | 2025 |
| Nicola Malone Associates Limited | Professional & scientific | 2007 |
| Nicola Ramsden Property Agent Ltd | Real estate | 2023 |
| Nicola Ruth Ltd | Professional & scientific | 2018 |
| Nicola Yates Limited | Information & communication | 2025 |
| Nicolaas Johannes Ltd | Real estate | 2021 |
| Nicolas DEL Ltd | Transport & logistics | 2024 |
| Nicole Bowden Holdings Ltd | Financial services | 2025 |
| Nicole Lavin Neurorehab Ltd | Health & social care | 2020 |
| Nicsol Limited | Wholesale & retail | 2013 |
| Nicusor Healthcare Limited | Health & social care | 2020 |
| Nidd Developments Limited | Real estate | 2001 |
| Nidhoggr Mead Co. Limited | Manufacturing | 2020 |
| Nifty Cars Ltd | Wholesale & retail | 2023 |
| Nifty Newt Productions Limited | Information & communication | 2011 |
| Nifty Sustainability CIC | Professional & scientific | 2019 |
| Nigde Resturant Limited | Financial services | 2024 |
| Nige Gray OUT of Hours Ltd | Health & social care | 2020 |
| Nigel Payne Tiling Limited | Construction | 2012 |
| Nigel Wyatt & Co. Limited | Professional & scientific | 1996 |
| Nigellas Pantry Ltd | Hospitality | 2023 |
| Nigerian Community Leeds | Other services | 2008 |
| Nigerian Yorkshire Communities Network UK CIC | Education | 2020 |
| Niggly Knee Running Club Ltd | Wholesale & retail | 2024 |
| Night and Day (Leeds) Limited | Administrative & support | 2022 |
| Night and Day Dent Ltd | Health & social care | 2020 |
| Nightgold Ltd. | Administrative & support | 2012 |
| Nightingale Housing Ltd | Real estate | 2019 |
| Nightjar Investments | Financial services | 2013 |
| Nightrain Entertainment Limited | Hospitality | 2018 |
| Niho Limited | Other services | 2024 |
| Nijjar Asset Management Ltd | Real estate | 2022 |
| Nika Transport Ltd | Transport & logistics | 2015 |
| Nikdan Ltd | Wholesale & retail | 2018 |
| Niketha Ltd | Real estate | 2024 |
| Nikhman Private Limited | Wholesale & retail | 2025 |
| Nikk Building Ltd | Construction | 2025 |
| Niko Express Ltd | Construction | 2024 |
| Niko Freight Ltd | Transport & logistics | 2018 |
| NIL Solutions Limited | Administrative & support | 2024 |
| Nila Solutions Limited | Information & communication | 2011 |
| Niland Financial Services Limited | Financial services | 2013 |
| Nile Coffee Leeds Ltd | Hospitality | 2026 |
| Nile Eats Ltd | Manufacturing | 2025 |
| Niloofar Limited | Transport & logistics | 2022 |
| Nilsson Golf Limited | Wholesale & retail | 2020 |
| Nima Delivery Ltd | Transport & logistics | 2020 |