| Novelty Communication Ltd | Other services | 2017 |
| Novenesis A.I Ltd | Information & communication | 2025 |
| Noviscio Ltd | Professional & scientific | 2025 |
| Novitas Ventures Ltd | Real estate | 2026 |
| Novocean Ltd | Professional & scientific | 2024 |
| Novogene (UK) Company Limited | Professional & scientific | 2014 |
| Novologix Ltd | Professional & scientific | 2026 |
| Novoscope Limited | Real estate | 2025 |
| Novowise Ltd | Wholesale & retail | 2025 |
| Novpak Industry Ltd | Extraterritorial | 2018 |
| Novum House (Cambridge) Management Company Ltd | Households | 2018 |
| Novumbio Limited | Professional & scientific | 2016 |
| Novus Titan LLP | | 2012 |
| NOW Serve Limited | Construction | 2022 |
| Nowce Limited | Information & communication | 2014 |
| Nowell Lodge Management Company Ltd | Households | 2018 |
| Noxprotekt Ltd | Manufacturing | 2017 |
| Noyia Auto Trim Co., Limited | Extraterritorial | 2020 |
| NPD Medical Limited | Health & social care | 2021 |
| Npeter Group Co., Ltd | Manufacturing | 2021 |
| Npml DEV Limited | Real estate | 2019 |
| Npworldwide Ltd | Wholesale & retail | 2024 |
| NPZ Technology Limited | Manufacturing | 2011 |
| NPZ UK Plant Breeding Ltd | Agriculture & fishing | 2005 |
| NR Commerce Ltd | Wholesale & retail | 2024 |
| NRC Recruitment & Events Limited | Hospitality | 2018 |
| NRG Partnership Ltd | Professional & scientific | 2019 |
| NRNR(NO1) Limited | Real estate | 2019 |
| NRNR(NO2) Limited | Real estate | 2020 |
| NRS Carpets Ltd | Wholesale & retail | 2006 |
| NS & Sons UK Ltd | Wholesale & retail | 2013 |
| Ns-Mc Consulting Ltd | Professional & scientific | 2019 |
| Ns-Mc Holdings Ltd | Financial services | 2022 |
| Nsdd Properties Ltd | Real estate | 2022 |
| Nseabra Ltd | Manufacturing | 2026 |
| Nseven IT Ltd | Information & communication | 2012 |
| Nsirc Limited | Extraterritorial | 2012 |
| NSK Lettings Ltd | Real estate | 2025 |
| NSN2024 Ltd | Transport & logistics | 2024 |
| NSR Contractors Limited | Wholesale & retail | 2006 |
| NSR World Limited | Wholesale & retail | 2022 |
| Ntanos Air Ltd | Manufacturing | 2023 |
| Ntnj Limited | Professional & scientific | 2015 |
| NU Quantum Ltd | Manufacturing | 2018 |
| Nubuke Limited | Administrative & support | 2014 |
| Nuclera Ltd | Professional & scientific | 2013 |
| Nuclyss Limited | Real estate | 2022 |
| Nuexcom Limited | Health & social care | 2003 |
| Nugen Energy Limited | Financial services | 2019 |
| Nugservices Ltd | Transport & logistics | 2025 |
| Nulhus Ltd | Professional & scientific | 2024 |
| Nulla Group Limited | Financial services | 2022 |
| Nulo Blue Limited | Information & communication | 2020 |
| Nulo Limited | Information & communication | 2019 |
| Numavera Ltd | Administrative & support | 2017 |
| Number 100 Geoconsulting Limited | Professional & scientific | 2025 |
| Numberdo Ltd | Real estate | 2020 |
| Numberik Ltd | Real estate | 2021 |
| Numbers Count Limited | Professional & scientific | 2001 |
| Numbertin Ltd | Real estate | 2020 |
| Numerato Limited | Financial services | 2026 |
| Numitas Limited | Administrative & support | 2013 |
| Nunulanka Ltd | Information & communication | 2019 |
| Nuomage Technology Co., Ltd | Extraterritorial | 2015 |
| Nurture Films Ltd | Information & communication | 2020 |
| Nurture Glow Ltd | Wholesale & retail | 2025 |
| Nusayba Properties Limited | Real estate | 2024 |
| Nuta Cristian Ltd | Manufacturing | 2023 |
| Nuta Eric Ltd | Manufacturing | 2024 |
| Nutrilution UK Ltd | Wholesale & retail | 2026 |
| Nutrition Trading Co., Ltd | Wholesale & retail | 2019 |
| Nutters Beauty Limited | Other services | 2012 |
| Nutters Hair & Beauty Limited | Other services | 2012 |
| Nutty Bean Coffee Company Limited | Administrative & support | 2009 |
| Nutu Composite Ltd | Manufacturing | 2025 |
| Nutucrs Ltd | Manufacturing | 2026 |
| Nuvovention Ltd | Professional & scientific | 2024 |
| NV Aviation Services Ltd | Education | 2024 |
| NVT (South) Limited | Manufacturing | 2007 |
| NW Contracts Ltd | Construction | 2025 |
| NWE Construction Limited | Construction | 2025 |
| Nxera Pharma UK Limited | Professional & scientific | 2007 |
| Nyala Ltd | Professional & scientific | 2019 |
| Nyla Assets Ltd | Real estate | 2025 |
| Nyobolt Limited | Professional & scientific | 2019 |
| Nywines Ltd | Wholesale & retail | 2010 |
| NZC Developments Limited | Construction | 2020 |
| Nøught International Limited | Manufacturing | 2023 |
| O&A Medical Ltd | Health & social care | 2022 |
| O'Brien Hotels Limited | Hospitality | 2023 |
| O'Neill Technology Solutions Limited | Professional & scientific | 2026 |
| O'Sullivan Group (UK) Limited | Extraterritorial | 2010 |
| O'Vesuvio Ltd | Hospitality | 2021 |
| O2 Worldwide Limited | Other services | 2015 |
| O2H Cowork Labs Limited | Professional & scientific | 2018 |
| O2H Limited | Professional & scientific | 2013 |
| O2H Nominees Limited | Professional & scientific | 2019 |
| Oadby Management Company Limited | Households | 2005 |
| Oak and the Cherry Interactive Limited | Professional & scientific | 2013 |
| Oak Boarding Kennels Limited | Other services | 2014 |