| Oranglow Ltd | Wholesale & retail | 2025 |
| Orbit One Limited | Information & communication | 2015 |
| Orchard Box Ltd | Wholesale & retail | 2015 |
| Orchard Care (South West) Limited | Health & social care | 2003 |
| Orchard Close Management (Cossington) Limited | Households | 1980 |
| Orchard Court Highbridge Limited | Households | 1989 |
| Orchard Hill Management Company Limited | Households | 2004 |
| Orchard Payroll Services Limited | Administrative & support | 2013 |
| Orchard Telecom Ltd | Information & communication | 2025 |
| Orchards Community Support - Community Interest Company | Hospitality | 2016 |
| Oresund Creative Ltd. | Information & communication | 2015 |
| Organic Milk Suppliers Co-Operative Limited | Other services | 1997 |
| Orient Foundation for Arts and Culture | Arts & recreation | 1983 |
| Origen DE Tierra Limited | Administrative & support | 2017 |
| Origin Developments Limited | Real estate | 2018 |
| Originate Group Ltd | Professional & scientific | 2026 |
| Orion Corporation Limited | Real estate | 1993 |
| Orion Lettings Ltd | Real estate | 2024 |
| Orla Residential Ltd | Real estate | 2024 |
| Orust Projects Ltd | Professional & scientific | 2020 |
| Orvaanta Ltd | Wholesale & retail | 2025 |
| Oscar 'N' Ollie's Ltd | Hospitality | 2019 |
| Oscar House Limited | Information & communication | 2021 |
| OSL Learning and Media Ltd | Information & communication | 2016 |
| Osos Services Limited | Professional & scientific | 2023 |
| Osprey Outdoors C.I.C | Health & social care | 2008 |
| Othara Ltd | Real estate | 2024 |
| Otho Limited | Professional & scientific | 2011 |
| Ottico Ltd | Information & communication | 2021 |
| Ottrex Ltd | Wholesale & retail | 2026 |
| Otty Civils Limited | Construction | 2019 |
| OUR Pool Limited | Real estate | 2017 |
| OUR Shalom Ltd | Health & social care | 2026 |
| Over and OUT Cleaning Limited | Administrative & support | 2026 |
| Overcombe House (WSM) Management Company Ltd | Households | 2016 |
| Overvale Mansions Management Company Limited | Households | 1997 |
| Ovidiutamas Ltd | Health & social care | 2020 |
| Ownidea Properties Ltd | Real estate | 2019 |
| OX Restaurants Ltd | Hospitality | 2018 |
| Oxbow Developments Limited | Construction | 2002 |
| Oxford Taxi Hire Limited | Other services | 2012 |
| Oxfordshire Taxi & Executive Services Limited | Transport & logistics | 2019 |
| Oxsy Ltd | Wholesale & retail | 2016 |
| Oxtane Performance Ltd | Manufacturing | 2026 |
| P & a Transport (South West) Limited | Transport & logistics | 2007 |
| P & D Burrisson Recycling Ltd | Water & waste | 2010 |
| P & M Carpentry and Building Ltd | Construction | 2022 |
| P & T (WSM) Limited | Real estate | 2008 |
| P B Holyday and SON Ltd. | Construction | 2015 |
| P F Sharrocks Ltd | Manufacturing | 2019 |
| P J Burke Limited | Hospitality | 2018 |
| P L Elliman Consultancy Services Limited | Professional & scientific | 2014 |
| P Orchard Ltd | Transport & logistics | 2015 |
| P&A Groundworks & Construction Services Limited | Construction | 2012 |
| P&A Photography Ltd | Information & communication | 2023 |
| P&A Property Development Limited | Real estate | 2026 |
| P. Phillips & Sons (Bridgwater) Limited | Construction | 1993 |
| P.D.S. Hitech Limited | Real estate | 2016 |
| P.N.E Building & Carpentry Ltd | Construction | 2025 |
| P.S 102 Ltd | Wholesale & retail | 2026 |
| P.S.P.S. U.K. Limited | Manufacturing | 2017 |
| Pacific Representation Limited | Administrative & support | 2003 |
| Packaging "No-How" Ltd | Administrative & support | 1998 |
| Packaging 2 Your Door Ltd | Wholesale & retail | 2017 |
| Pact Social Consultancy Ltd | Professional & scientific | 2021 |
| Pactsocial Ltd | Professional & scientific | 2022 |
| Padls Limited | Real estate | 2020 |
| Padster Ltd | Financial services | 2023 |
| Paignton Car Company Limited | Wholesale & retail | 2005 |
| Pailliot Healthcare Limited | Health & social care | 2025 |
| Pailliot Investments Limited | Health & social care | 2022 |
| Painless Chris Limited | Arts & recreation | 2006 |
| Palander Investments Ltd | Administrative & support | 2019 |
| Pallet Storage Limited | Transport & logistics | 2019 |
| PALLET2PATIO Ltd | Manufacturing | 2023 |
| Palm Tree Property (South West) Ltd | Real estate | 2020 |
| PALS3 Ltd | Wholesale & retail | 2026 |
| PAN Globus Limited | Wholesale & retail | 2009 |
| Panache 30 Ltd | Hospitality | 2024 |
| Panda Telecom Limited | Construction | 2012 |
| Pankow Contracting Limited | Construction | 2024 |
| Pankow Limited | Professional & scientific | 2023 |
| Paradise Landscape Ltd | Professional & scientific | 2024 |
| Paradise Studios Ltd | Hospitality | 2019 |
| Paragon Court Maintenance Limited | Households | 1979 |
| Paragon Road Management Committee Limited | Households | 2022 |
| Pardip Consultancy Ltd | Wholesale & retail | 2016 |
| Park Court (Weston-Super-Mare) Limited | Households | 1969 |
| Park Farm Bristol Ltd | Transport & logistics | 2020 |
| Park House (Weston-Super-Mare) Limited | Health & social care | 2002 |
| Park Lodge 72 Upper Church Road Management Company Limited | Households | 2001 |
| Park ROW Boutique Salon Ltd | Other services | 2017 |
| Park View (Clevedon) Management Company Ltd | Households | 2002 |
| Parker Models Limited | Manufacturing | 1998 |
| Parkhouse Psychology Service Limited | Administrative & support | 2010 |
| Parklands Tower Walk Management Company Limited | Households | 1989 |
| Parsons Farewell Limited | Households | 2007 |
| Parsons Farm Supplies Ltd | Agriculture & fishing | 2013 |
| Parsons Scrap Ltd | Real estate | 2012 |
| Party.Party Hire Limited | Information & communication | 2014 |