| Rits Ltd | Transport & logistics | 2021 |
| River Health Ltd | Health & social care | 2026 |
| Riverstones Composites Ltd | Administrative & support | 2025 |
| Riyash Ltd. | Other services | 2015 |
| Rizaland Ltd | Real estate | 2011 |
| RJE Capital Ltd | Construction | 2026 |
| RKM (NU Shine) Ltd | Manufacturing | 2011 |
| RL Plumbing Ltd | Construction | 2018 |
| RNB Hospitality Limited | Professional & scientific | 2007 |
| RNB Properties Limited | Real estate | 2017 |
| Roadworks Information Limited | Information & communication | 2011 |
| Roaf Marine Services Ltd | Transport & logistics | 2019 |
| Roberts Farm Residents Limited | Households | 1991 |
| Robertswood Developments Ltd | Construction | 2011 |
| Robin Celebi Ltd | Information & communication | 2019 |
| Robin Cleaning Service Ltd | Administrative & support | 2025 |
| Robin of Heathfield Limited | Financial services | 2014 |
| Robson Warren Architects Ltd. | Professional & scientific | 1993 |
| Robsons (Northwood) LLP | | 2005 |
| Robsons (Pinner) LLP | | 2007 |
| Robsons (Rickmansworth) Limited | Real estate | 2014 |
| Robsons Pinner Lettings Limited | Real estate | 2022 |
| Robsons Residential Lettings Limited | Real estate | 2011 |
| Roccaforte Limited | Professional & scientific | 2014 |
| Roche Property Enterprises Limited | Real estate | 2011 |
| Rockport Software Limited | Information & communication | 1997 |
| Roger Comer Limited | Professional & scientific | 2015 |
| Roman & Black Limited | Construction | 2015 |
| Romu Labs Ltd | Wholesale & retail | 2023 |
| Ronald Janssen Ltd | Professional & scientific | 2020 |
| Ronnie & Tobs Ltd | Hospitality | 2025 |
| Roof Masters West London Limited | Construction | 2015 |
| Rooflight Technical Services Ltd | Professional & scientific | 2026 |
| Room Three Ltd | Information & communication | 2018 |
| Roopra Property Ltd | Real estate | 2021 |
| Rootland Property Ltd | Real estate | 2023 |
| Rosa Global Limited | Professional & scientific | 2022 |
| Rosalyn Care Services Limited | Health & social care | 2018 |
| Rosby Properties Limited | Real estate | 2025 |
| Rosedale Care Ltd | Health & social care | 2021 |
| Rosewood Garages Limited | Wholesale & retail | 2005 |
| Ross & Co Care Limited | Health & social care | 2024 |
| Round Pixel Ltd | Information & communication | 2024 |
| Rovico Limited | Real estate | 1968 |
| RR Scaffolding and Access Hire Limited | Manufacturing | 2017 |
| RS Grips Ltd | Information & communication | 2020 |
| RS Training & Sales Ltd | Wholesale & retail | 2022 |
| RSR Technologies Limited | Information & communication | 2016 |
| Rubina II Limited | Health & social care | 2024 |
| Rudra Limited | Real estate | 2023 |
| Runningmusket Ltd | Information & communication | 2024 |
| Russell Martin Financial Services Limited | Financial services | 2020 |
| Russell Martin Legal Services Limited | Administrative & support | 2006 |
| Russell Phillips Limited | Professional & scientific | 2004 |
| Russiateleradio Worldwide Limited | Arts & recreation | 2000 |
| Ruth White Homes Limited | Hospitality | 1998 |
| RWB Carpentry Ltd | Construction | 2017 |
| Rysaco Ltd | Arts & recreation | 2024 |
| S & B Rawat Associates Limited | Wholesale & retail | 2010 |
| S & I Equity Limited | Real estate | 2004 |
| S & J Consultancy Services Limited | Professional & scientific | 2017 |
| S Fletcher Services Limited | Transport & logistics | 2025 |
| S O Consultants Limited | Health & social care | 2015 |
| S PEL Consulting Ltd | Wholesale & retail | 2025 |
| S R a Limited | Construction | 1994 |
| S Renu Two Ltd | Real estate | 2024 |
| S.A.H Nursing Homes Limited | Other services | 1999 |
| S.B. Consulting (Services) Limited | Administrative & support | 2012 |
| S1 Botanicals Ltd | Wholesale & retail | 2026 |
| S3G Consulting Services Limited | Information & communication | 2018 |
| S5G Real Estate Limited | Real estate | 2019 |
| Saavaas Limited | Wholesale & retail | 2021 |
| Sabre Sports Coaches Limited | Arts & recreation | 2013 |
| Sadie Jones Limited | Information & communication | 2012 |
| Sadikali's Limited | Information & communication | 2010 |
| Safe Food Limited | Professional & scientific | 2005 |
| Safetech Services Limited | Construction | 2019 |
| Safety Support Solutions Limited | Professional & scientific | 2012 |
| Saffron D'Or Ltd | Hospitality | 2015 |
| Saffron Developments (Bucks) Limited | Construction | 2015 |
| Saffron Place Ltd | Hospitality | 2025 |
| Saft Drinks Limited | Manufacturing | 2025 |
| Sagax Properties Ltd | Real estate | 2024 |
| Saianand Limited | Real estate | 2021 |
| Sairam Consultancy Services Ltd | Professional & scientific | 2016 |
| Salah Property Limited | Real estate | 2017 |
| Salem Glass Limited | Construction | 1982 |
| Salisbury Financial Services Limited | Financial services | 1986 |
| Sally Tilleray Consulting Limited | Professional & scientific | 2015 |
| Salon 77 GX Limited | Other services | 2020 |
| Samra Finance Ltd | Financial services | 2025 |
| Samson 4X4 Generators Limited | Information & communication | 2023 |
| Samson Lighting Limited | Professional & scientific | 2008 |
| Sanctified Film Limited | Information & communication | 2023 |
| Sandhills Associates Ltd | Professional & scientific | 2021 |
| Sanuka Professionals Ltd | Professional & scientific | 2013 |
| SAR Management Limited | Real estate | 2015 |
| Sarah Pasco Jones Ltd | Administrative & support | 2001 |
| Sarah Tompkins Limited | Health & social care | 2013 |
| Sarah Trowse Limited | Information & communication | 2012 |