| Optic-Kleer Limited | Wholesale & retail | 2003 |
| Optimal Cloud Solutions Limited | Information & communication | 2024 |
| Optimus Equations Ltd | Information & communication | 2011 |
| Opulent Vintage Ltd | Wholesale & retail | 2025 |
| Orchard Orthotics & Footcare Ltd | Health & social care | 2013 |
| Orchard Retreat Staycation Ltd | Real estate | 2022 |
| Origin Care Homes (Beeston) Limited | Health & social care | 2021 |
| Origin Care Homes (Holbeach) Limited | Health & social care | 2021 |
| Origin Care Homes (Humberston) Limited | Health & social care | 2022 |
| Origin Care Homes (Oadby) Limited | Health & social care | 2021 |
| Origin Care Homes (West Bridgford) Limited | Health & social care | 2021 |
| Orthopaedic Medico-Legal Services Limited | Health & social care | 2012 |
| Orton Investments Limited | Financial services | 1973 |
| OS Trans Service Limited | Transport & logistics | 2022 |
| Osprey Lodges Limited | Professional & scientific | 2000 |
| Osvo Building Services Limited | Construction | 2017 |
| Oundle Garden Centre Ltd | Wholesale & retail | 2025 |
| Ozzy - House Limited | Real estate | 2018 |
| P & Co Developments Ltd | Construction | 2025 |
| P & S Carwash Limited | Other services | 2019 |
| P & T East Midlands Limited | Financial services | 2017 |
| P Capps Farming Ltd | Agriculture & fishing | 2018 |
| P I Trading Limited | Administrative & support | 2005 |
| P V Motors Limited | Wholesale & retail | 2024 |
| P W Heating and GAS Ltd | Construction | 2023 |
| P&N Anderson & SON Ltd | Agriculture & fishing | 2024 |
| P. E. ROE & SON Limited | Agriculture & fishing | 2007 |
| P.G.Hair Limited | Other services | 2016 |
| P.P. Load Ltd | Transport & logistics | 2019 |
| P.R. Flooring Limited | Wholesale & retail | 2003 |
| PAB Communications Limited | Information & communication | 2019 |
| Padelset Ltd | Construction | 2026 |
| Padley Project Management Ltd | Construction | 2023 |
| Page Paper Limited | Wholesale & retail | 1995 |
| Pagefault Limited | Information & communication | 2013 |
| Pajatec Limited | Real estate | 2013 |
| Palm Horizon Limited | Wholesale & retail | 2026 |
| Palm Swift Logistics Ltd | Transport & logistics | 2024 |
| Pam's Angels Ltd | Health & social care | 2026 |
| PAR Electrical Lincs Ltd | Construction | 2022 |
| Paradigm LDN Ltd | Wholesale & retail | 2024 |
| Paradise Farm Estate Ltd | Agriculture & fishing | 2012 |
| Parkfresh Vegetables Limited | Agriculture & fishing | 2000 |
| Parkinson Harness Technology Limited | Manufacturing | 2001 |
| Parklane Financial Solutions Ltd | Information & communication | 2023 |
| Parklane Group Limited | Financial services | 2026 |
| Parvez Property Group Limited | Real estate | 2023 |
| Passion for Talent Management Ltd | Arts & recreation | 2019 |
| Patient Artisan Wines Ltd | Extraterritorial | 2022 |
| Patose Limited | Health & social care | 2008 |
| Patrick Property Limited | Real estate | 2018 |
| PAU8 Ltd | Administrative & support | 2017 |
| Paul Smith & Associates Ltd | Professional & scientific | 2017 |
| Paul Timby Investments Services Limited | Financial services | 2007 |
| Pavko Express Ltd | Transport & logistics | 2017 |
| Pawtector Products Ltd | Wholesale & retail | 2024 |
| PAY 4 Fresh Ltd | Wholesale & retail | 2024 |
| Payferz Ltd | Wholesale & retail | 2022 |
| PC Windscreen Repairs Ltd | Wholesale & retail | 2021 |
| PDR Property Law Training Centre Ltd | Education | 2022 |
| PDR Property Lawyers Ltd | Professional & scientific | 2007 |
| PE & Sons Ltd | Hospitality | 2025 |
| Peace of Mind Plumbing and Heating Ltd | Construction | 2023 |
| Peak BD Ltd | Administrative & support | 2024 |
| Pearls Lettings Ltd | Real estate | 2022 |
| Peebles & Hilton Limited | Health & social care | 2011 |
| Pelenis Transport Ltd | Transport & logistics | 2026 |
| Pembroke Real Estate LLC | | 2004 |
| Pengethley Potatoes Limited | Agriculture & fishing | 1989 |
| Penny Processors UK Ltd | Professional & scientific | 2024 |
| Perfect Chips Ltd | Agriculture & fishing | 2019 |
| Perichef Ltd | Hospitality | 2020 |
| Pestinator UK Limited | Administrative & support | 2014 |
| Peter Smith Commercials Limited | Wholesale & retail | 2017 |
| Peter Smith Truck & Van Limited | Wholesale & retail | 2019 |
| Petra Invest Ltd | Real estate | 2023 |
| Petriman Logistic Ltd | Transport & logistics | 2018 |
| Petrol Driver Ltd | Transport & logistics | 2024 |
| Pfh-Uk Limited | Wholesale & retail | 2025 |
| Phil Haines Coaches Limited | Transport & logistics | 2005 |
| Phil Limb Agri Services Ltd | Manufacturing | 2019 |
| Philip Hills Physiotherapy Ltd | Health & social care | 2016 |
| Phjk Ltd | Administrative & support | 2016 |
| Phoenix Haulage Solutions Limited | Administrative & support | 2024 |
| Phoenix Highvista Venture Capital Partners LP | | 2021 |
| Phoenix IT Tech Limited | Information & communication | 2025 |
| Phone Site Ltd | Wholesale & retail | 2024 |
| Phones From Home Ltd | Wholesale & retail | 2025 |
| Picketts Produce Ltd | Wholesale & retail | 2025 |
| Picknshop Ltd | Wholesale & retail | 2025 |
| Pickworths Residential Living Limited | Health & social care | 2021 |
| Pigeon Electronic Ltd | Wholesale & retail | 2025 |
| Pigeon Sport Ltd | Information & communication | 2025 |
| Pilgrim Agricultural Contractors Limited | Administrative & support | 2008 |
| Pilgrim Blinds (Trade) Ltd | Manufacturing | 2013 |
| Pilgrim Fire Protection Ltd | Public administration | 2020 |
| Pilgrim Foodservice Limited | Wholesale & retail | 2005 |
| Pilgrim Link Ltd | Other services | 2016 |
| Pilgrim Mansions (Boston) Limited | Households | 2007 |
| Pilgrim Securities Limited | Financial services | 1976 |