| Mystery of Concrete Ltd | Manufacturing | 2021 |
| N & T'S Quality Conservatories Limited | Construction | 2007 |
| N K a Traders Ltd | Wholesale & retail | 2024 |
| N.Leonardi Limited | Construction | 2014 |
| Naboulsi Limited | Hospitality | 2022 |
| Nana Print Ltd | Wholesale & retail | 2021 |
| Nantha Trade Limited | Wholesale & retail | 2025 |
| Nasgri Properties Ltd | Real estate | 2023 |
| Nashola Limited | Health & social care | 2013 |
| Nathants Limited | Health & social care | 2019 |
| Natured Support Ltd | Health & social care | 2020 |
| Navrad Medical Ltd | Real estate | 2023 |
| Naytom Consulting Limited | Professional & scientific | 2019 |
| Neat Vehicles Limited | Manufacturing | 2015 |
| Nelson Autos Ltd | Wholesale & retail | 2025 |
| Nelsons Mill Ltd | Manufacturing | 2021 |
| Nest Lettings and Maintenance Ltd | Real estate | 2020 |
| Nest Tour Ltd | Administrative & support | 2025 |
| New Beginnings Training Academy Limited | Other services | 2024 |
| New Farm Fuels Limited | Wholesale & retail | 2014 |
| New Lees Garden Ltd | Hospitality | 2018 |
| Newbury Oak Limited | Information & communication | 2021 |
| Newhouse Developments Ltd | Construction | 2020 |
| Nexgen Property Maintenance & Landscaping Ltd | Construction | 2024 |
| Nexob Trading Ltd | Wholesale & retail | 2026 |
| Nexora Software Limited | Information & communication | 2026 |
| Next Chapters Housing Solutions Ltd | Health & social care | 2022 |
| Next Level Auto Service Ltd | Wholesale & retail | 2023 |
| Next Level Landscaping & Groundworks Limited | Administrative & support | 2025 |
| Nexus (Midlands) Limited | Construction | 2021 |
| NG Decorating Ltd | Construction | 2025 |
| NH Kirkby Limited | Hospitality | 2019 |
| Ni-Vek Technical Solutions Limited | Professional & scientific | 2024 |
| Nick Bowler Garage Services Limited | Wholesale & retail | 2017 |
| Nicudinca Ltd | Administrative & support | 2020 |
| Nikomimix Ltd | Construction | 2022 |
| Nimade Property Sourcing Ltd | Administrative & support | 2025 |
| Nivi Investment Limited | Real estate | 2026 |
| NJG Safety Services Limited | Other services | 2019 |
| NKT Aquatics Limited | Wholesale & retail | 2024 |
| NO Pain NO Gain Ltd | Transport & logistics | 2018 |
| Noen Limited | Construction | 2023 |
| Northwood Convenience Ltd | Wholesale & retail | 2023 |
| Nottingham Rebels Ltd | Education | 2024 |
| Nottinghamshire Memorials Ltd | Wholesale & retail | 2007 |
| Nottinghamshire Mining Heritage Centre CIC | Education | 2022 |
| Notts Admin Services Ltd | Public administration | 2026 |
| Novus Connect Limited | Construction | 2025 |
| Noxy Ltd | Wholesale & retail | 2024 |
| NPN Electronics Ltd | Wholesale & retail | 2020 |
| Nu-Jeneration Ltd | Health & social care | 2019 |
| Nulook Projects Ltd | Professional & scientific | 2021 |
| Nxstage Medical UK, Ltd. | Administrative & support | 2011 |
| O.K. Services (East Midlands) Limited | Manufacturing | 2003 |
| Oakfern Family Butchers Limited | Wholesale & retail | 2008 |
| Oasis Outdoor Living Limited | Wholesale & retail | 2023 |
| Oatly Mansfield Limited | Hospitality | 2025 |
| Ocean Designs (GB) Limited | Wholesale & retail | 2006 |
| OCM Engineering Ltd | Professional & scientific | 2016 |
| Oddball Business Consultancy Ltd | Administrative & support | 2025 |
| Oddball Properties Ltd | Construction | 2026 |
| Odushop Ltd | Wholesale & retail | 2025 |
| OE Direction Ltd | Arts & recreation | 2025 |
| OI Blow Limited | Professional & scientific | 2026 |
| Oikos Developments & Lettings Limited | Real estate | 2021 |
| Okkes Limited | Hospitality | 2019 |
| One Blue Studio Ltd | Professional & scientific | 2018 |
| Online Plans Limited | Professional & scientific | 2022 |
| Ontime Sameday Ltd | Transport & logistics | 2024 |
| Orange Homes & Property Limited | Real estate | 2021 |
| Orange Homes Midlands Limited | Construction | 2019 |
| Orange Mountain Limited | Administrative & support | 2023 |
| Orca Group Limited | Other services | 2015 |
| Orca Pro Developments Limited | Construction | 2016 |
| Orire Surgimed Ltd | Health & social care | 2024 |
| Oscars Fencing Contractors Ltd | Construction | 2024 |
| Oscarson Ltd | Transport & logistics | 2025 |
| Osiris MR Limited | Professional & scientific | 2009 |
| Ostler East Midlands Limited | Hospitality | 2020 |
| OUR Version Ltd | Real estate | 2019 |
| P & a Maintenance Ltd | Construction | 2022 |
| P & R Plant Services Ltd | Administrative & support | 2019 |
| P B Auto Factors Limited | Wholesale & retail | 2005 |
| P R Taylor Polishing Limited | Manufacturing | 2014 |
| P&K Investment Management Ltd | Extraterritorial | 2015 |
| Panashe PVT Ltd | Health & social care | 2020 |
| Paradise Rise Limited | Wholesale & retail | 2025 |
| Paraiso Tanning Ltd | Other services | 2019 |
| Parallux Ltd | Arts & recreation | 2026 |
| Paramedicex Ltd | Public administration | 2015 |
| Parmars (Huthwaite) Limited | Real estate | 2021 |
| Passionate Pets, Animal Feed and Country Store Limited | Wholesale & retail | 2023 |
| Patheon UK Services Ltd | Wholesale & retail | 2025 |
| Paul Bradford Distribution Limited | Transport & logistics | 2014 |
| Paultrucktrans Ltd | Transport & logistics | 2010 |
| Pawluk Transport Ltd | Transport & logistics | 2017 |
| Pawsome Vets Ltd | Professional & scientific | 2023 |
| PAY My Builder Ltd | Construction | 2026 |
| PCI Two Limited Partnership | | 2010 |
| Peach, Peach and Peach Limited | Health & social care | 2016 |