| RPY Consultancy Limited | Administrative & support | 2022 |
| RR Global Infotech Ltd | Information & communication | 2013 |
| RR Recruitment Ltd | Transport & logistics | 2021 |
| RS Gleaves Property Limited | Real estate | 2016 |
| RS Purple Investments Ltd | Real estate | 2017 |
| RSB Urban Properties Ltd | Real estate | 2026 |
| RSF Consultancy Limited | Administrative & support | 2025 |
| Rskg Ltd | Construction | 2011 |
| RSM Education Limited | Financial services | 2024 |
| RSM Technology Limited | Information & communication | 1998 |
| RSR Investments Limited | Other services | 2018 |
| RSV Investments Limited | Real estate | 2022 |
| RTL Commercial Ltd | Financial services | 1922 |
| Rubin Bros Ltd | Manufacturing | 2021 |
| Ruby HAS UK Limited | Transport & logistics | 2021 |
| Ruby J Limited | Professional & scientific | 2010 |
| Rubysea Limited | Construction | 2006 |
| Ruddocks & Co. Accounting Services Ltd | Professional & scientific | 2008 |
| Ruhna Ltd | Real estate | 2019 |
| Rukhsanas Ltd | Other services | 2016 |
| Runestone Games Limited | Information & communication | 2004 |
| Runners & Stunners CIC | Arts & recreation | 2026 |
| Runuk Limited | Administrative & support | 2018 |
| Rush Holdings FI LLP | | 2017 |
| Rushden Supermarket Ltd | Wholesale & retail | 2022 |
| Rutland House Management Company (Brecon) Limited | Professional & scientific | 1992 |
| Ruuger and Partners Ltd | Manufacturing | 2012 |
| Ruvansh & Enakshi Properties Limited | Real estate | 2024 |
| RV Developments (Surrey) Limited | Construction | 2018 |
| RVM Accountants Ltd | Professional & scientific | 2021 |
| RW Music Limited | Information & communication | 2018 |
| Rwsm Management Limited | Administrative & support | 2014 |
| RYB Limited | Hospitality | 2016 |
| RYE WAX Ltd | Administrative & support | 2014 |
| RYE Waxed CIC | Information & communication | 2024 |
| S & G Developments Limited | Construction | 2001 |
| S & K Capital Limited | Administrative & support | 2017 |
| S & S Pharmachem Limited | Wholesale & retail | 1999 |
| S & T Acquisitions Ltd | Health & social care | 2024 |
| S & T G Medical Services Limited | Health & social care | 2017 |
| S & T G Property Services Limited | Real estate | 2023 |
| S (Satnam) Motors Limited | Wholesale & retail | 2024 |
| S a Glazing Services Limited | Administrative & support | 2013 |
| S Advisory Ltd | Professional & scientific | 2024 |
| S D Geeves Haulage Ltd | Transport & logistics | 2019 |
| S Doshi Limited | Professional & scientific | 2023 |
| S Essential Enterprise Ltd | Wholesale & retail | 2026 |
| S J Cooper Construction Limited | Construction | 2018 |
| S J T C Limited | Construction | 2001 |
| S L E Spedition Ltd | Transport & logistics | 2025 |
| S Lynch Trading Limited | Wholesale & retail | 2026 |
| S T Site Services Limited | Construction | 2010 |
| S&N Installation Ltd | Construction | 2019 |
| S&N Property Investments Ltd | Real estate | 2021 |
| S&S Security Services Limited | Public administration | 2016 |
| S&U Umar Enterprises Ltd | Construction | 2018 |
| S. E. Harvey Limited | Administrative & support | 2015 |
| S. Khan Anaesthetic Services Limited | Health & social care | 2007 |
| S.E.H Kelly Limited | Administrative & support | 2013 |
| S.I Buildings Solutions Ltd | Construction | 2024 |
| S.J.H. Group Limited | Information & communication | 2017 |
| S.S.J. Brothers Limited | Real estate | 2009 |
| S3M3 UK Limited | Real estate | 2025 |
| S7 Talent Management Limited | Professional & scientific | 2025 |
| S8OM Limited | Information & communication | 2026 |
| S90HAIR Ltd | Other services | 2026 |
| Saadiagallani Ltd | Wholesale & retail | 2021 |
| Saaki Limited | Real estate | 2005 |
| Saba Properties Limited | Real estate | 2005 |
| Sabji Box Ltd | Wholesale & retail | 2020 |
| Sadytrans Limited | Transport & logistics | 2019 |
| Safe Access Scaffolding Limited | Construction | 2012 |
| Safeguarding Children 21ST Century Limited | Health & social care | 2025 |
| Safely Snatched Ltd | Health & social care | 2020 |
| Safety First London Ltd | Construction | 2020 |
| Safety Reports Limited | Other services | 2018 |
| Saffron CHC Specialists Ltd | Health & social care | 2025 |
| Saffron Clinical Limited | Health & social care | 2023 |
| Sage Ventures Limited | Real estate | 2021 |
| Sage Vision Limited | Construction | 2025 |
| Saggese Cafe Limited | Hospitality | 2002 |
| Sagir Pharmaceuticals Limited | Health & social care | 2023 |
| Sahhara Limited | Health & social care | 2016 |
| Sahhara Property Limited | Real estate | 2023 |
| Saifora Ltd | Wholesale & retail | 2026 |
| Sakana Ltd | Hospitality | 2015 |
| Saki Soft Limited | Information & communication | 2000 |
| Sakura Beach Limited | Administrative & support | 2021 |
| Sakura Natural Candle Company Limited | Administrative & support | 2024 |
| SAL Beauty Hair Ltd | Other services | 2023 |
| SAL Trading Limited | Administrative & support | 2016 |
| Salesfounder International Ltd | Professional & scientific | 2016 |
| Salma Holdings Ltd | Real estate | 2022 |
| Salon Sixteen Limited | Other services | 2009 |
| Salted Caramel Ltd | Professional & scientific | 2018 |
| SAM Financial and Universal Investments UK Ltd | Construction | 2022 |
| SAM Sheedy Ltd | Health & social care | 2023 |
| Samack Solutions Ltd | Construction | 2023 |
| Samantha Pope Ltd | Professional & scientific | 2019 |
| Samgoatlifters Ltd | Administrative & support | 2023 |