| OUR Place Cafe Ltd | Hospitality | 2026 |
| OUR Precious Tots Limited | Education | 2011 |
| Ourworld Corporation Ltd | Information & communication | 2024 |
| OUT There Events Limited | Other services | 2010 |
| OUT There Media Production Limited | Manufacturing | 2019 |
| Outerview Ltd | Professional & scientific | 2025 |
| Outlet Express Limited | Wholesale & retail | 2024 |
| Outmost Care Ltd | Health & social care | 2018 |
| Outsha Ltd | Wholesale & retail | 2024 |
| Outsiders Store CDY Ltd | Wholesale & retail | 2018 |
| Outsiders Store Ltd | Wholesale & retail | 2017 |
| Outsource Finance Function & Accountancy Ltd | Professional & scientific | 2022 |
| OV Finance Limited | Other services | 2024 |
| OV SME Services Ltd | Administrative & support | 2023 |
| OVA Cricket Limited | Extraterritorial | 2018 |
| OVA Limited | Health & social care | 2021 |
| Overbroom Properties Limited | Extraterritorial | 2021 |
| Overgold Limited | Extraterritorial | 1996 |
| Overpassclothinguk Ltd | Wholesale & retail | 2025 |
| Oversley Properties Ltd | Real estate | 2021 |
| Owentor Limited | Extraterritorial | 1981 |
| Oxford College of Science and Technology Ltd | Education | 2025 |
| OXO Homes Ltd | Real estate | 2022 |
| Oxted Holdings Ltd | Real estate | 2021 |
| Oxted SUB Ltd | Real estate | 2021 |
| Oyigiyigi (UK) Limited | Professional & scientific | 2022 |
| Oyin Oriki Entertainment Ltd | Wholesale & retail | 2026 |
| OYJ Ltd | Real estate | 2026 |
| Oyster Venture Partners Limited | Other services | 2019 |
| OYY Lubavitch Boys School | Education | 2009 |
| OZ Business Consulting Ltd | Wholesale & retail | 2014 |
| Ozone Creative Ltd | Information & communication | 2025 |
| Ozone Properties Ltd | Real estate | 2025 |
| Ozzies-Fur-Ever-Friends Limited | Other services | 2023 |
| Ozzys Barbershop Ltd | Other services | 2021 |
| P & S Vekaria Limited | Wholesale & retail | 2018 |
| P B Commercials Limited | Manufacturing | 2016 |
| P Barbers Ltd | Other services | 2024 |
| P D Drylining Ltd | Construction | 2026 |
| P Murthy Limited | Health & social care | 2016 |
| P R B V Associates Limited | Real estate | 2017 |
| P Richardson Decorations Ltd | Construction | 2023 |
| P Rothschild Finance Ltd | Financial services | 2002 |
| P&A Catering Northwest Ltd | Hospitality | 2023 |
| P&C Healthcare Ltd | Health & social care | 2013 |
| P&E Holdings Limited | Real estate | 2022 |
| P&L Supplies Services Ltd | Administrative & support | 2025 |
| P&Q Fashion Ltd | Wholesale & retail | 2026 |
| P&S Property MCR Ltd | Real estate | 2020 |
| P.T Jalanterbaik Ltd | Real estate | 2025 |
| PA WIZ Limited | Information & communication | 2023 |
| PAB Homefix Ltd | Construction | 2025 |
| Pace Logistics Services Limited | Transport & logistics | 2001 |
| Pacewise Ecommerce Ltd | Wholesale & retail | 2026 |
| Paddington Bear Childcare Ltd | Health & social care | 2025 |
| Paddy MAC Leisure Ltd | Hospitality | 2015 |
| Padi Property Services Limited | Real estate | 2022 |
| Paer Management Ltd | Real estate | 2020 |
| Paget Road Estates Limited | Real estate | 2017 |
| Pagoda Projects Ltd | Education | 2017 |
| Paidnow Ltd | Information & communication | 2025 |
| Paint and Pause Ltd | Arts & recreation | 2025 |
| PAL Infra Ltd | Real estate | 2025 |
| PAL Properties Ltd | Real estate | 2026 |
| Palace Rentals Ltd | Real estate | 2023 |
| Palatine Holdings Ltd | Real estate | 2021 |
| Palatine Inn Ltd | Hospitality | 2024 |
| Palm Match Limited | Real estate | 2016 |
| Palmgenesis Ltd | Information & communication | 2024 |
| Palmpsl Ltd | Wholesale & retail | 2023 |
| PAN Pacific Service Ltd | Wholesale & retail | 2023 |
| Pan's Linkage Ltd | Wholesale & retail | 2026 |
| Panacea Training and Support Ltd | Education | 2025 |
| Pancontext Limited | Professional & scientific | 2001 |
| Panda Mami Management Group Ltd | Information & communication | 2021 |
| Pandor Estates Ltd | Real estate | 2004 |
| Pandora Estates Limited | Real estate | 2014 |
| PANEL8 Ltd | Wholesale & retail | 2025 |
| Panteli Living Ltd | Wholesale & retail | 2025 |
| Papenburg Estates Ltd | Real estate | 2020 |
| Papenburg Properties Ltd | Real estate | 2020 |
| Paradigm Network Limited | Information & communication | 2025 |
| Paradise Consortium Limited | Financial services | 2022 |
| Paradise Investment and Trades Ltd | Wholesale & retail | 2021 |
| Paradise UK Investments Ltd | Real estate | 2026 |
| Paradise Ventures Limited | Arts & recreation | 2018 |
| Paragon Digital Trade Ltd | Wholesale & retail | 2025 |
| Paragon.Io Ltd | Information & communication | 2023 |
| Parakeet Limited | Real estate | 2026 |
| Paramount Cultivated Ltd | Education | 2022 |
| Paramount NW Ltd | Real estate | 2025 |
| Paramount Waste Ltd | Extraterritorial | 2017 |
| Parcelhat Ltd | Information & communication | 2025 |
| Parchment Studio Limited | Professional & scientific | 2025 |
| Parcor Ltd | Professional & scientific | 2020 |
| Paresh Local Limited | Wholesale & retail | 2019 |
| Parfitt Group Ltd | Wholesale & retail | 2025 |
| Parima Estates Limited | Extraterritorial | 2017 |
| Park Bench Foods Limited | Wholesale & retail | 2018 |
| Park Central Maldon Limited | Wholesale & retail | 2021 |