| Ochre Framing Limited | Manufacturing | 2003 |
| Old Hastings Preservation Society Limited | Arts & recreation | 1958 |
| Old Heath Management Company Limited | Real estate | 1992 |
| Old Town Inns Limited | Hospitality | 2003 |
| ON Line Properties Limited | Professional & scientific | 2001 |
| ON My Doorstep Limited | Information & communication | 2005 |
| ON Stage Conference Limited | Other services | 2002 |
| One Lyndhurst Road Limited | Households | 2005 |
| Onwards Together Therapy Ltd | Health & social care | 2016 |
| Onya Limited | Wholesale & retail | 2013 |
| OP Construction Sussex Ltd | Construction | 2023 |
| Orange Aero Limited | Wholesale & retail | 1994 |
| Orchard Produce Limited | Wholesale & retail | 1995 |
| Orlingbury Developments Limited | Real estate | 2003 |
| Orostream International Contracts Limited | Construction | 1997 |
| Orphan AID Malawi | Other services | 2008 |
| OSI Consulting Limited | Professional & scientific | 2007 |
| Osprey Clarke Limited | Administrative & support | 1992 |
| Outhouse Publishing Limited | Information & communication | 2006 |
| Ovalvick Limited | | 1982 |
| Over-All Construction (South East) Limited | Construction | 2004 |
| Oxberry Management Limited | Households | 2002 |
| Oxford Villas Limited | Real estate | 1954 |
| Oxygen Digital Ltd | Information & communication | 2007 |
| Ozland Limited | Hospitality | 1977 |
| Oztex Services Ltd. | Other services | 2002 |
| P & G Trower Limited | Construction | 2002 |
| P C Secretaries Ltd. | Administrative & support | 2003 |
| P M Restoration Limited | | 1988 |
| P R Davies Limited | Professional & scientific | 2003 |
| P Simmons Heating Limited | Construction | 2005 |
| P.A.L. Plastering Limited | | 1985 |
| Paddockhall Investments Limited | Financial services | 1985 |
| Palmeira Square NOS 2-6 Limited | Households | 1992 |
| Pandiserv UK Limited | Administrative & support | 2005 |
| Papertronic Ltd | Information & communication | 2005 |
| Paramo Limited | Manufacturing | 1992 |
| Paras Properties Limited | Real estate | 2003 |
| Parfarm Security Limited | Administrative & support | 2023 |
| Parima Properties Limited | Households | 1961 |
| Park Lane Developments (South East) Limited | Extraterritorial | 1994 |
| Park Lane Homes (South East) Ltd | Construction | 2000 |
| Park Lane Investment Properties Limited | Real estate | 1994 |
| Parke Property Management Co. Limited | Households | 1981 |
| Parkers Business Services Limited | Professional & scientific | 2007 |
| Parkervale Limited | Information & communication | 2005 |
| Parkstone Design Consultants Ltd | Other services | 2019 |
| Paskins Hotel Limited | Hospitality | 1995 |
| Paspic Limited | Administrative & support | 1995 |
| Patrick Wilson Limited | Administrative & support | 2003 |
| Paul Cheal Plumbing & Heating Limited | Construction | 2003 |
| Paul Masters Electrical Ltd | Professional & scientific | 2005 |
| Pavilion Contracting Limited | Professional & scientific | 2004 |
| Pavilion Homes (Sussex) Limited | Construction | 1997 |
| Pavilion Reproductions (Brighton) Limited | Water & waste | 1972 |
| Paving and Drainage Hastings Limited | Professional & scientific | 1986 |
| Paxton Access Limited | Manufacturing | 1985 |
| PDH Accountants Limited | Professional & scientific | 2003 |
| Pdsm Limited | Construction | 1994 |
| Pelham Commercial Properties Limited | Real estate | 2005 |
| Penguin Software Limited | Information & communication | 1990 |
| Penn House (Hove) NO.2 Limited | Households | 1997 |
| Penny Stones Limited | Real estate | 2000 |
| Pennyroyal RYE Limited | Wholesale & retail | 2003 |
| Penta International Limited | Education | 2004 |
| Penton Associates Ltd | Transport & logistics | 2000 |
| Pepstar Food Ltd | Hospitality | 2019 |
| Perchgreen Property Management Limited | Extraterritorial | 2003 |
| Perfect Finance Limited | Professional & scientific | 2023 |
| Peridot Jewellers Limited | Manufacturing | 2002 |
| Perinon Limited | Hospitality | 2000 |
| Permers Professional (Rose Hill) Limited | Real estate | 1983 |
| Peskett Investments Limited | Financial services | 2006 |
| Peter Collingridge Antiques Limited | Wholesale & retail | 2002 |
| Peter J. Taylor Limited | Other services | 2003 |
| Peter Mcnally Limited | Construction | 2002 |
| Petrie Hosken Media Limited | Administrative & support | 2007 |
| Petsitters Limited | Extraterritorial | 1994 |
| PGL (Sussex) Ltd | Other services | 2002 |
| PGL Holdings Limited | Professional & scientific | 2016 |
| Phase Electrical Distributors Limited | Wholesale & retail | 2002 |
| Pheebert`S Garden Statuary Limited | Wholesale & retail | 2006 |
| Philip Hall Associates Limited | Professional & scientific | 2003 |
| Philip R Dann Limited | Agriculture & fishing | 2004 |
| Philippa Weitz Training Limited | Other services | 1997 |
| Phillip a. Bancroft (Contractors) Limited | | 1986 |
| Phoenix Cycles Company Limited | Manufacturing | 2001 |
| Phoenix Scientific Industries (UK) Limited | Other services | 1994 |
| Phoenix Scientific Industries Limited | Manufacturing | 1987 |
| Picador Management Limited | Professional & scientific | 2006 |
| Picot Consulting Limited | Professional & scientific | 2007 |
| Piers Chater Robinson Limited | Extraterritorial | 1980 |
| PIG City Incorporated Limited | Arts & recreation | 1988 |
| Piltdown Golf Club Ltd | Arts & recreation | 2019 |
| PIN Hill Autos Limited | Wholesale & retail | 2001 |
| Pine Glade Homes Limited | Real estate | 2003 |
| Pine Time Trading Limited | Wholesale & retail | 2003 |
| Pinewood (Teignmouth) Management Limited | Households | 1997 |
| Pippingford Estate Co.Limited(The) | Real estate | 1962 |
| Pithon Limited | Professional & scientific | 2000 |