| New GEN Netball Ltd | Education | 2025 |
| Newline Mgmt Holdings Ltd | Professional & scientific | 2019 |
| Next Chapter Recruitment Ltd | Administrative & support | 2022 |
| NFP Group Limited | Financial services | 2020 |
| NFP People Limited | Administrative & support | 2018 |
| Nixon Building & Co Ltd | Construction | 2022 |
| NN Pulse Limited | Information & communication | 2015 |
| NOA TC Limited | Education | 2024 |
| Noble HR Services Ltd | Administrative & support | 2025 |
| Noble Signature Properties Ltd | Other services | 2019 |
| North Beds Osteopaths Limited | Health & social care | 2008 |
| Notes Creative Ltd | Arts & recreation | 2018 |
| Nova Business Finance Ltd | Financial services | 2024 |
| Np&Vb Assoc Ltd | Transport & logistics | 1992 |
| Number 6 Contracting Ltd | Information & communication | 2011 |
| Nunn Associates Ltd | Administrative & support | 2014 |
| O&C Construction Ltd | Construction | 2018 |
| Oakridge (North Kilworth) Management Company Limited | Households | 2021 |
| Oakridge Capital Developments Ltd | Real estate | 2025 |
| OBD Properties Limited | Households | 2019 |
| ODD Sock Services Ltd | Information & communication | 2017 |
| Olney Barbers HD Ltd | Other services | 2018 |
| Olney Butchers Limited | Wholesale & retail | 2015 |
| Olney Care Services Limited | Health & social care | 2010 |
| Olney Garages Limited | Wholesale & retail | 2023 |
| Olney House Limited | Real estate | 2016 |
| Olney IS Kind CIC | Health & social care | 2023 |
| Olney Kitchen Restaurant & Bar Limited | Hospitality | 2026 |
| Olney Pilates Studio Ltd | Arts & recreation | 2022 |
| Olney Pizzeria Limited | Hospitality | 2019 |
| Olney Rugby Football Club Limited | Arts & recreation | 2021 |
| Olney Rugby Football Social Club Limited | Arts & recreation | 2021 |
| Olney Vehicle Solutions Limited | Wholesale & retail | 2016 |
| Olney Workspace Ltd | Real estate | 2026 |
| Oomph Yoga and Mindfulness Children's Club Ltd | Arts & recreation | 2023 |
| Orchard Press (Olney) Limited | Manufacturing | 2004 |
| Orchard Wills Limited | Professional & scientific | 1998 |
| Osborn Architectural Design Ltd | Professional & scientific | 2009 |
| Osborn Design Studio Limited | Professional & scientific | 2006 |
| Osborn Designers Limited | | 2008 |
| Oskaruk Limited | Professional & scientific | 2007 |
| Osprey GAS Solutions Ltd | Other services | 2020 |
| Ourview Limited | Administrative & support | 2013 |
| Outlier Ascents Ltd | Administrative & support | 2025 |
| Pair Education Limited | Education | 2016 |
| Pandic Ltd | Professional & scientific | 2010 |
| Pathway to Success Limited | Education | 2011 |
| Payter UK Limited | Manufacturing | 2020 |
| Pechrian Systems Limited | Information & communication | 2015 |
| Penmayne Studio Ltd | Information & communication | 2026 |
| Perfect Deliveries Ltd | Transport & logistics | 2024 |
| Perfect Plant Deal UK Limited | Wholesale & retail | 2022 |
| PERK6 Limited | Professional & scientific | 2018 |
| Pet Industry Federation Limited | Other services | 2010 |
| Peter Bushnell Associates Limited | Professional & scientific | 1994 |
| Pgac Property Ltd | Real estate | 2024 |
| Phine's Delight Ltd | Hospitality | 2024 |
| Phonebox Magazine Limited | Manufacturing | 2004 |
| Plum & Ashby England Limited | Wholesale & retail | 2014 |
| Polaris Cyber Ltd | Professional & scientific | 2026 |
| Positive Climb Ltd | Information & communication | 2026 |
| Practical Progression Limited | Administrative & support | 2005 |
| Premiair Helicopters Limited | Transport & logistics | 2020 |
| Prep Your SET Limited | Administrative & support | 2020 |
| Pro Tessellate Limited | Professional & scientific | 2015 |
| Pro Yarn Studio Limited | Wholesale & retail | 2024 |
| Pro-Rol Engineering Limited | Manufacturing | 1990 |
| Professional Training Direct Limited | Education | 2007 |
| Progressive Bits Ltd | Information & communication | 2017 |
| Progroupmk Ltd | Construction | 2018 |
| Projector Lifting Service Limited | Manufacturing | 1984 |
| Propski Limited | Arts & recreation | 2013 |
| Propventures (Brip) LLP | | 2024 |
| Provadis Limited | Professional & scientific | 2002 |
| Purchasing Insight Limited | Professional & scientific | 2013 |
| Pure Creative Studios Ltd | Administrative & support | 2015 |
| Qdonomy Limited | Information & communication | 2019 |
| Quality Improvement Solutions Ltd | Professional & scientific | 2023 |
| Quercus Tree Specialists Ltd | Agriculture & fishing | 2022 |
| Quickshift Ltd | Transport & logistics | 2024 |
| R C F Developments Limited | Construction | 2009 |
| R Good Services Ltd | Construction | 2015 |
| R.J. Harper Limited | Professional & scientific | 2003 |
| R.S.P.Flooring Limited | Construction | 2014 |
| Racketpadel Limited | Arts & recreation | 2025 |
| Raff & ROO Limited | Wholesale & retail | 2025 |
| Rasso Limited | Hospitality | 2021 |
| RCG Connect Ltd | Professional & scientific | 2024 |
| Real Belgian Fries Ltd | Hospitality | 2014 |
| Real Belgian Frites Ltd | Hospitality | 2023 |
| Red Wave Communications Limited | Professional & scientific | 2006 |
| Redfern Property Group Ltd | Real estate | 2024 |
| Redfern Property Management Ltd | Real estate | 2025 |
| Reel Scene Productions Ltd | Information & communication | 2024 |
| Reel Scene Talent Ltd | Administrative & support | 2024 |
| Reen Limited | Health & social care | 2022 |
| Remedial Property Solutions Ltd | Construction | 2025 |
| Resort Fiduciary Services Limited | Administrative & support | 2004 |
| Resurco Limited | Professional & scientific | 2017 |
| Reynolds Property Renovations Ltd | Construction | 2026 |