| O M Contractors Limited | Construction | 2015 |
| O&H Homes Ltd | Real estate | 2026 |
| O'Grady (Electrical) Engineering Ltd | Construction | 2013 |
| O.M.G Plumbing & Heating Limited | Manufacturing | 1997 |
| Oakfield Asset Management Limited | Professional & scientific | 2021 |
| Oakmere Property Group Limited | Construction | 2024 |
| Oasis Sun & Beauty Ltd | Other services | 2026 |
| OC Freehold Limited | Real estate | 2024 |
| Ocean Granite Limited | Extraterritorial | 2014 |
| Octopus Dynamics Limited | Professional & scientific | 2024 |
| Odin Quality Security Ltd | Administrative & support | 2021 |
| Odyssey Mmxxii Ltd | Real estate | 2022 |
| OEE Precision Ltd | Wholesale & retail | 2020 |
| OFF the Ropes CIC | Arts & recreation | 2023 |
| OH First Limited | Health & social care | 2023 |
| OKG Limited | Professional & scientific | 2020 |
| Old Station Studio CIC | Professional & scientific | 2026 |
| Oleg 2020 Limited | Transport & logistics | 2020 |
| Olivers Cafe & Bistro Ltd | Hospitality | 2026 |
| Oll’S Speed & Machine Ltd | Wholesale & retail | 2026 |
| Omnis Developments Ltd | Construction | 2022 |
| Omnis Services Ltd | Construction | 2022 |
| One ASH Training Limited | Education | 2008 |
| Onepointfiveco Ltd | Information & communication | 2022 |
| Onlygolf Limited | Arts & recreation | 2026 |
| Oops Haulage Ltd | Wholesale & retail | 2017 |
| Open IT Ltd | Information & communication | 2024 |
| Open Solutions (Osuk) Limited | Real estate | 2012 |
| Optimum Fitness (NW) Limited | Arts & recreation | 2014 |
| Optimum Security Services Ltd | Administrative & support | 2021 |
| Optiva Ltd | Arts & recreation | 2011 |
| Orbit Construction Services Ltd | Construction | 2022 |
| Orbit Labs Group Ltd | Information & communication | 2025 |
| Order Locally Ltd | Hospitality | 2020 |
| Orfic Group Limited | Financial services | 2022 |
| Orfic Technology Limited | Professional & scientific | 2022 |
| Orion Strategic Ltd | Administrative & support | 2026 |
| ORP Preston Limited | Professional & scientific | 2025 |
| Orthohold Limited | Health & social care | 2025 |
| Oskilec Engineering Ltd | Professional & scientific | 2024 |
| OSX Beauty Ltd | Wholesale & retail | 2023 |
| Otentic Medics Limited | Health & social care | 2013 |
| Otis Retail Limited | Hospitality | 2026 |
| Outback Garden Design Ltd | Professional & scientific | 2022 |
| Ovation Doors & Windows Ltd | Construction | 2023 |
| Overarch Solutions Ltd | Information & communication | 2026 |
| Overtime Records Ltd | Wholesale & retail | 2025 |
| Owen Aesthetics & Healthcare Consultancy Ltd | Health & social care | 2023 |
| O’Grady Engineering & Construction Ltd | Construction | 2020 |
| P Owen Property Limited | Households | 2016 |
| P&G Fencing Limited | Administrative & support | 2017 |
| P&G Property Rentals Limited | Real estate | 2021 |
| P&R Bars Limited | Hospitality | 2020 |
| P.C. Catering Limited | Wholesale & retail | 2003 |
| P.D.L Access Ltd | Construction | 2009 |
| P.J. Motors (Widnes) Ltd | Wholesale & retail | 2013 |
| P.P.H. North West Limited | Construction | 2018 |
| P2GWIDNES Limited | Hospitality | 2019 |
| Packaroo Ltd | Wholesale & retail | 2025 |
| PAL PAK Corrugated Limited | Manufacturing | 1995 |
| Palindor Holdings Limited | Financial services | 2025 |
| Palltech Pallets Limited | Other services | 2018 |
| Palou Properties Ltd | Real estate | 2022 |
| PAN Asian Limited | Hospitality | 2024 |
| Pandora Factory Blinds & Shutters Ltd | Wholesale & retail | 2025 |
| Paola’S Salon Limited | Other services | 2025 |
| PAP Print Limited | Professional & scientific | 1981 |
| Paragon Partnership Holdings Ltd | Construction | 2020 |
| Paragon PE Ltd | Manufacturing | 2004 |
| Paragon Technical PE Services Limited | Manufacturing | 2017 |
| Paramount Construction & Project Services Ltd | Construction | 2025 |
| Paramount Media NW Limited | Other services | 2019 |
| Parapro Services Limited | Administrative & support | 2025 |
| Park Road East Projects Limited | Construction | 2021 |
| Parkville Trading Limited | Real estate | 2010 |
| Parry Property Holdings Limited | Real estate | 2016 |
| Party World Widnes Limited | Wholesale & retail | 2024 |
| Pascal's Smash Ltd | Hospitality | 2026 |
| Pathway Motor Company of Warrington Ltd | Wholesale & retail | 2015 |
| Patisserie Lane Ltd | Wholesale & retail | 2023 |
| Patrick Rada Ltd | Transport & logistics | 2021 |
| Patsoom Ltd | Hospitality | 2020 |
| Paul Anthony Costing Limited | Professional & scientific | 2026 |
| Paul Goodbun Limited | Construction | 2004 |
| Paul Oates Consulting Ltd | Information & communication | 2020 |
| Paul Robinson Ltd | Transport & logistics | 2023 |
| Paul's (Widnes) Limited | Hospitality | 2009 |
| Paula Restaurant Ltd | Hospitality | 2025 |
| Pauls (Derby Road) Ltd | Hospitality | 2023 |
| Pawtraits Limited | Professional & scientific | 2022 |
| Paxmobil Ltd | Wholesale & retail | 2023 |
| PAY Point Services Limited | Administrative & support | 2025 |
| Pays Renovations Ltd | Real estate | 2021 |
| PB Elec. Limited | Construction | 2016 |
| PB Hall Bathrooms Ltd | Construction | 2025 |
| PCN Forklift Truck Services Ltd | Transport & logistics | 2006 |
| PCP Missold Limited | Financial services | 2017 |
| PD Law (NW) Ltd | Professional & scientific | 2011 |
| PDC Security and Leisure Limited | Administrative & support | 2009 |
| PDL Transport Limited | Transport & logistics | 2022 |