| River Stour Navigation Company Limited | Transport & logistics | 2006 |
| River Stour Trust Limited (the) | Other services | 1968 |
| Riverbank Rights Limited | Information & communication | 2017 |
| Riverside Walk Management Company Limited | Real estate | 1974 |
| RJA Carpentry & Building Ltd | Construction | 2018 |
| RJM Elite Building Limited | Construction | 2011 |
| RK Curios Limited | Wholesale & retail | 2023 |
| Rlre Limited | Construction | 2026 |
| RM2 Recruitment Ltd | Administrative & support | 2023 |
| RO20 Ltd | Real estate | 2019 |
| Road Ahead Transport (Consultancy & Training) Services Limited | Transport & logistics | 2008 |
| Robert Perry Carpentry Contracts Limited | Construction | 2007 |
| Robin Platt Limited | Other services | 2010 |
| Robins ROW Insurance Holdings Limited | Financial services | 2006 |
| Robins ROW Limited | Financial services | 1984 |
| Robinson Homes (Suffolk) Limited | Construction | 2021 |
| Robinson Homes Rental Limited | Real estate | 2024 |
| Robison-Smith Developments Limited | Construction | 2005 |
| Robison-Smith Holdings Limited | Real estate | 2021 |
| Robson Ecology Limited | Professional & scientific | 2016 |
| Rockmount Road RTM Company Limited | Households | 2010 |
| Rogerson Holdings Limited | Financial services | 1994 |
| Rogue Couture Ltd | Manufacturing | 2020 |
| Rogue Culture Ltd | Manufacturing | 2020 |
| Rolf Utilitys Limited | Construction | 2022 |
| Roma Solutions Limited | Administrative & support | 2013 |
| ROO the Day Films Ltd | Information & communication | 2024 |
| Ropers Court Management Company Limited | Households | 2004 |
| ROR Power Limited | Manufacturing | 2013 |
| Roscoe Educational Ltd | Education | 2018 |
| Rosslyn & Talbot Limited | Construction | 2018 |
| Rowe Holdings Limited | Agriculture & fishing | 2025 |
| Rowe Homes Limited | Real estate | 2013 |
| Rowe Retreats Ltd | Hospitality | 2025 |
| Rowfant Mansions RTM Company Limited | Households | 2019 |
| Rowhedge Farm Limited | Agriculture & fishing | 1997 |
| RPG.1 Ltd | Construction | 2025 |
| RSS Car Sales Limited | Wholesale & retail | 2024 |
| RTD UK Partners Ltd | Arts & recreation | 2015 |
| Ruchi Foods International Ltd | Wholesale & retail | 2023 |
| Rush Transport Solutions Ltd | Transport & logistics | 2021 |
| Russell Concrete Pumps Ltd | Construction | 2024 |
| Russian Doll Shop Ltd | Wholesale & retail | 2018 |
| Ryder-Bayes Accounting Ltd | Professional & scientific | 2023 |
| S & C Brickworks Ltd | Construction | 2014 |
| S & K News Limited | Wholesale & retail | 2019 |
| S & K News Wivenhoe Limited | Wholesale & retail | 2022 |
| S & M Maintenance Ltd | Other services | 2003 |
| S & P Property Holdings Ltd | Real estate | 2018 |
| S Lawrence Enterprises Ltd | Administrative & support | 2006 |
| S&Sa Property Limited | Real estate | 2025 |
| S.A. Castle Limited | Manufacturing | 2002 |
| S.G.Wade Limited | Agriculture & fishing | 1961 |
| S.J.Ustscim-It Ltd | Construction | 2018 |
| S.M. Cook Decorators Limited | Construction | 2002 |
| S1VDH Ltd | Construction | 2015 |
| S7EER Driving Ltd | Transport & logistics | 2025 |
| Safe Scaffolding Solutions Ltd | Construction | 2026 |
| Sailship Training and Learning for Life | Education | 2014 |
| Salisbury House Residents (Watford) Limited | Households | 2008 |
| Sally's Home-Care Ltd | Health & social care | 2024 |
| Salmon Financial Solutions Limited | Financial services | 2026 |
| Salmon Will Writers Limited | Professional & scientific | 2026 |
| Salter & Mckenna LLP | | 2020 |
| SAM Kerruish Sports Analysis Solutions Limited | Information & communication | 2024 |
| Sams Investments Ltd | Real estate | 2017 |
| Samuel Estates and Holding Properties Ltd | Real estate | 2022 |
| Sanders Lacoray Textiles Limited | Manufacturing | 1990 |
| Sanders Textiles Limited | Manufacturing | 2007 |
| Sanica Building Materials Limited | Wholesale & retail | 2017 |
| Sarah Oliver Limited | Information & communication | 2007 |
| Sarah-Jane Money Limited | Extraterritorial | 2012 |
| Saraille Solutions Ltd | Information & communication | 2025 |
| Saunders Brothers Limited | Real estate | 2002 |
| SAVAL09 Ltd | Information & communication | 2020 |
| Savoy Bathrooms Limited | Wholesale & retail | 2021 |
| Saxham Studios Limited | Professional & scientific | 1988 |
| Scandinavian Montage Services Limited | Professional & scientific | 2016 |
| Scarab Watches Limited | Wholesale & retail | 2025 |
| Scientific Partners Limited | Financial services | 2023 |
| Scln Limited | Information & communication | 2026 |
| Scofield Clinic Ltd | Health & social care | 2018 |
| Scot Lewis Associates Limited | Professional & scientific | 1995 |
| Scotlewis Ltd | Administrative & support | 2024 |
| Scott Groom General Building & Carpentry Ltd | Construction | 2025 |
| Sculpture Dance Arts Ltd | Education | 2026 |
| SDE Contracts Limited | Construction | 2017 |
| SDE Group Holdings Limited | Financial services | 2022 |
| SDE Group Limited | Financial services | 2020 |
| SDL Contracts Limited | Construction | 2013 |
| SDM Clinics Ltd | Health & social care | 2021 |
| Sdsdab Limited | Construction | 2012 |
| Seago Butler Stopps Financial Services Limited | Financial services | 2001 |
| Search and Secure Limited | Administrative & support | 2026 |
| Seasonal Colour LAB Ltd | Construction | 2022 |
| Sector East Limited | Transport & logistics | 2022 |
| Secure Itad Limited | Information & communication | 2014 |
| Seedlings Collective CIC | Arts & recreation | 2026 |
| Seedlings Studio Ltd | Arts & recreation | 2024 |
| Seekars Sudbury LP | | 2012 |