| Proaxis Consultancy Ltd | Professional & scientific | 2025 |
| Probatest Limited | Administrative & support | 2010 |
| Probity Construction Ltd | Construction | 2023 |
| Probiz Estate Ltd | Real estate | 2024 |
| Probuild & Construction Ltd | Construction | 2022 |
| Procare Holdings Ltd | Real estate | 2025 |
| Procare Property Maintenance Ltd | Households | 2023 |
| Procare Vision Ltd | Health & social care | 2009 |
| Procida-I Ltd | Information & communication | 2025 |
| Procomm Signalling Limited | Administrative & support | 2006 |
| Proconsys Ltd | Information & communication | 2011 |
| Procuredge Ltd | Other services | 2009 |
| Procurefect Consultancy Limited | Professional & scientific | 2012 |
| Procyon Property Investments Limited | Real estate | 2021 |
| Prodav Ltd | Construction | 2021 |
| Prodecor Design Limited | Construction | 2015 |
| Prodeo Energies Ltd | Information & communication | 2026 |
| Prodigal Love CIC | Health & social care | 2013 |
| Prodigy Technologies Ltd | Information & communication | 2011 |
| Production Technical Services Limited | Construction | 2014 |
| Productions SL Limited | Construction | 2017 |
| Productivv Technologies Limited | Information & communication | 2016 |
| Products R US Ltd | Wholesale & retail | 2025 |
| Productworx Ltd | Wholesale & retail | 2020 |
| Professional Academy of London Ltd | Professional & scientific | 2015 |
| Professional BB Pointing Ltd | Construction | 2018 |
| Professional Dental Indemnity Limited | Financial services | 2017 |
| Professional Engineering Services Global Ltd | Professional & scientific | 2024 |
| Professional Learning and Consulting Hub Limited | Information & communication | 2012 |
| Professional Services (International) PLC | Professional & scientific | 2007 |
| Professional Signalling Services Limited | Real estate | 2000 |
| Professional UK Estate Agent Ltd | Real estate | 2020 |
| Professional Welders Ltd | Construction | 2014 |
| Professor Farhadi Limited | Health & social care | 2024 |
| Proficient Advisors Ltd | Real estate | 2024 |
| Proficient Investments Ltd | Real estate | 2026 |
| Proficiere Limited | Information & communication | 2024 |
| Profikarma UK Ltd | Information & communication | 2024 |
| Profin Solutions Ltd | Professional & scientific | 2023 |
| Profit Big UK Limited | Hospitality | 2022 |
| Profit Centre Limited | Professional & scientific | 2011 |
| Progress Carib Cafe Ltd | Hospitality | 2025 |
| Progress Minded Ltd | Education | 2013 |
| Progress Steel Ltd | Wholesale & retail | 2024 |
| Progressive Health Ltd | Health & social care | 2024 |
| Progressive IT Services Ltd | Information & communication | 2015 |
| Progressive Planners UK Ltd | Professional & scientific | 2025 |
| Progressive UK Education Ltd | Education | 2025 |
| Prohan Ltd | Real estate | 2020 |
| Prohire Agency Ltd | Other services | 2020 |
| Project Alfa Limited | Manufacturing | 2022 |
| Project Commitment Limited | Construction | 2015 |
| Project E Catering Limited | Wholesale & retail | 2023 |
| Project Indigo Ltd | Real estate | 2018 |
| Project KRS Limited | Financial services | 2014 |
| Project Management and Engineering Services Ltd | Construction | 2026 |
| Project Marshall Ltd | Construction | 2021 |
| Project MGM Limited | Construction | 2019 |
| Project Partnership Alliance Limited | Professional & scientific | 2009 |
| Project Procure Ltd | Professional & scientific | 2008 |
| Project Shanti Ltd | Information & communication | 2025 |
| Project Spindle IHC UK 2 Limited | Financial services | 2025 |
| Project Treasures Ltd | Real estate | 2013 |
| Project VLR Limited | Construction | 2025 |
| Project XXX GBS Ltd | Construction | 2014 |
| Project:Digital Limited | Information & communication | 2010 |
| Projectify Limited | Professional & scientific | 2023 |
| Projects Resources Limited | Information & communication | 2014 |
| Projekt 964 Limited | Wholesale & retail | 2019 |
| Prologue Opera Ltd | Arts & recreation | 2022 |
| Prolux Chauffeurs Ltd | Transport & logistics | 2025 |
| Promede Limited | Construction | 2006 |
| Prometheus First Limited | Professional & scientific | 2021 |
| Prometheus Security and Safety Solutions Ltd | Administrative & support | 2020 |
| Prominence Care & Training Limited | Health & social care | 2021 |
| Prominens Limited | Real estate | 2018 |
| Prominent Estates Limited | Real estate | 2016 |
| Prominent Legal Limited | Professional & scientific | 2019 |
| Promoting to Strive Group Ltd | Health & social care | 2024 |
| Promoting Youth Ltd | Health & social care | 2022 |
| Promoveo Limited | Real estate | 2019 |
| Promozon Technologies Ltd | Information & communication | 2024 |
| Prompt Courier Ltd | Transport & logistics | 2019 |
| Prompt Research Laboratories Limited | Information & communication | 2024 |
| Promptum Delivery Ltd | Transport & logistics | 2021 |
| Pronaia Ltd | Other services | 2025 |
| Prop Wealth Limited | Real estate | 2023 |
| Propa Fast Food Limited | Hospitality | 2025 |
| Propacea Limited | Information & communication | 2006 |
| Propagate Distribution Ltd | Professional & scientific | 2025 |
| Propco Management Ltd | Real estate | 2024 |
| Propcore Partners Limited | Construction | 2025 |
| Propell Trading Ltd | Information & communication | 2023 |
| Propello Holdings Limited | Financial services | 2022 |
| Propello Press Limited | Professional & scientific | 2022 |
| Propelo Support Services Limited | Administrative & support | 2025 |
| Propenergy Ltd | Financial services | 2024 |
| Proper Slices Pizza Limited | Wholesale & retail | 2025 |
| Properfinishes Ltd | Construction | 2018 |
| Properkey Technologies Ltd | Information & communication | 2022 |