| Nesh! Republic Ltd | Information & communication | 2011 |
| NET Natives Partners LLP | | 2012 |
| Netloc Holdings Limited | Financial services | 2017 |
| Neuraflash Ltd | Information & communication | 2024 |
| New Approach Solutions Limited | Professional & scientific | 2020 |
| New Court (Ringwood) Limited | Households | 1962 |
| New Forest Aggregate Ltd | Transport & logistics | 2019 |
| New Forest Bacon Limited | Agriculture & fishing | 2002 |
| New Forest Bell Tents Limited | Hospitality | 2013 |
| New Forest Cider Limited | Manufacturing | 2010 |
| New Forest Communications Ltd | Wholesale & retail | 2001 |
| New Forest Confectionery Ltd | Wholesale & retail | 2012 |
| New Forest Construction Limited | Construction | 2025 |
| New Forest Country Store Limited | Wholesale & retail | 2025 |
| New Forest Heat Pumps Ltd | Construction | 2026 |
| New Forest Mind Body Spirit CIC | Health & social care | 2025 |
| New Forest Mobile Mechanics Ltd | Professional & scientific | 2024 |
| New Forest Osteopathy Ltd | Health & social care | 2014 |
| New Forest PIE Company Limited | Hospitality | 2025 |
| New Forest Public House Holdings Ltd | Hospitality | 2023 |
| New Forest Safety Ltd | Professional & scientific | 2023 |
| New Forest Shortbread Ltd | Manufacturing | 2020 |
| New Forest Spirits Ltd | Manufacturing | 2017 |
| New Retail Holdings Limited | Wholesale & retail | 2026 |
| Nexas Consulting Limited | Information & communication | 2012 |
| NFM Developments Limited | Construction | 2018 |
| NG Manco Limited | Households | 2005 |
| Nice JOB Rigging Limited | Information & communication | 2012 |
| Niltava Limited | Professional & scientific | 2012 |
| Ninth Throne Ltd | Wholesale & retail | 2021 |
| Nisthill Wind Farm Limited | Construction | 2022 |
| Nitchopath Ltd | Health & social care | 2025 |
| NO Name Leisure Limited | Hospitality | 2023 |
| NO7 Small Holdings Limited | Real estate | 2024 |
| Noble Threads Boutique Ltd | Wholesale & retail | 2026 |
| Nobody's Business Limited | Manufacturing | 2023 |
| NON Fumo Flue Systems Limited | Wholesale & retail | 1985 |
| Noohn Limited | Hospitality | 2020 |
| Noose Limited | Extraterritorial | 2026 |
| Norcroft Court (Management) Limited | Households | 1966 |
| Northfield Property Solutions Ltd | Construction | 2007 |
| Northshore Risk Solutions Limited | Financial services | 2013 |
| Northwood Tyre and MOT Centre Ltd | Wholesale & retail | 2023 |
| Notp Freehold Limited | Households | 2023 |
| NPT Resources Limited | Administrative & support | 2020 |
| NUA Health Ltd | Health & social care | 2024 |
| Nugen Creatives Ltd | Professional & scientific | 2020 |
| Nursery Care (Shirley) Ltd | Construction | 2015 |
| Nvisionise Ltd | Information & communication | 2025 |
| O.E.M. Europe Limited | Health & social care | 1988 |
| Oak at Lyndhurst Ltd | Hospitality | 2023 |
| Oak Lodge Residents (Ferndown) Limited | Households | 2022 |
| Oak Manor Verwood Management Company Limited | Households | 2007 |
| Oak-Craft Traditional Buildings Limited | Professional & scientific | 1998 |
| Oakcraft Limited | Professional & scientific | 2000 |
| Oaklan Construction Limited | Construction | 2018 |
| Oakley Court (Ringwood) Freehold Limited | Households | 2013 |
| Oaks Drive (ST. Leonards) Management Limited | Other services | 2003 |
| Oaktree HR & Business Consulting Limited | Professional & scientific | 2023 |
| Oakwood (Talbot Woods) Limited | Households | 1983 |
| Oatley Veterinary Orthopaedics Ltd | Professional & scientific | 2023 |
| OB Retail Ltd | Wholesale & retail | 2026 |
| Ocean 398 Ltd | Extraterritorial | 2013 |
| Ocean Broadband Ltd | Information & communication | 2024 |
| Ocean Images Limited | Professional & scientific | 2000 |
| Ocean Jade Ltd | Other services | 2025 |
| Ocean View Marketing Ltd | Administrative & support | 2021 |
| Oceanside Management Limited | Real estate | 2003 |
| Octane Enterprises Ltd | Wholesale & retail | 2025 |
| Octopus Farm Limited | Information & communication | 2017 |
| Offshore Paddle Ltd | Wholesale & retail | 2018 |
| OG Sport Ltd. | Manufacturing | 1994 |
| OG Sport Services Ltd | Manufacturing | 2003 |
| OH Sherbet Ltd | Professional & scientific | 2022 |
| Ohana Therapy Limited | Education | 2021 |
| Old Christchurch Road LLP | | 2006 |
| Old H. a. H Ltd | Hospitality | 2022 |
| Old Mill Flats Ringwood (Management) Limited(The) | Households | 1978 |
| Olex Projects Ltd | Construction | 2022 |
| Oliver's Cupboard Brand Ltd | Manufacturing | 2018 |
| Ollie Quinn Limited | Wholesale & retail | 2014 |
| ON Your Feet Presentations Limited | Administrative & support | 2012 |
| One Lion Holdings Ltd | Real estate | 2020 |
| One on One Adult Centre Limited | Wholesale & retail | 1999 |
| One Zero Contractors (PSC) Ltd | Administrative & support | 2017 |
| Open Mind Practice Limited | Health & social care | 2025 |
| Opex Leasing Ltd | Administrative & support | 2023 |
| Opium Recovery Services Ltd | Transport & logistics | 2022 |
| Opta Sports Data Limited | Information & communication | 2001 |
| Optimise Retail Ltd | Wholesale & retail | 2017 |
| Optimum Cyber Support Ltd | Extraterritorial | 2024 |
| Optimum Ventilation Management Ltd | Construction | 2025 |
| Opulentfx Ltd | Other services | 2025 |
| Orange Blossom Contracts Limited | Other services | 2019 |
| Orchard Court Freehold New Milton Limited | Households | 2022 |
| Original Cafe Group Ltd | Hospitality | 2023 |
| Original Vape Shop (Southbourne) Ltd | Wholesale & retail | 2019 |
| Original Vape Shop Barrack Limited | Wholesale & retail | 2025 |
| Oroel Ltd | Professional & scientific | 2019 |
| Ortus Freehold Limited | Households | 2021 |