| R3NCONSULTING Ltd | Professional & scientific | 2020 |
| RA Land Rovers Ltd | Wholesale & retail | 2021 |
| RA Partners Ltd | Information & communication | 2010 |
| Rabbit Industrial Flooring Limited | Construction | 2017 |
| Rabble Place Limited | Professional & scientific | 2015 |
| Rachel Gilmore Limited | Other services | 2008 |
| Radiantfr and Wellness Limited | Other services | 2026 |
| Radical Living Ltd | Wholesale & retail | 2020 |
| Radio Relay Limited | Information & communication | 2018 |
| Raege Limited | Financial services | 2018 |
| RAM Trustees Limited | Financial services | 2025 |
| Rami 22 Real Estate Ltd | Households | 2012 |
| Ranmore Car Concierge and Storage Ltd | Transport & logistics | 2024 |
| Ranmore Fine Motor Cars Ltd | Wholesale & retail | 2023 |
| Ranmore Properties Ltd | Real estate | 2021 |
| Ranmore Residential Limited | Real estate | 2022 |
| RAR Trading Ltd | Wholesale & retail | 2025 |
| Rare Aesthetics UK Ltd | Other services | 2025 |
| Rare Forms Nutrition Limited | Wholesale & retail | 2023 |
| Rascals Retreat Limited | Hospitality | 2023 |
| Rathfinny Wine Estate Limited | Manufacturing | 2010 |
| Raven Accounting Ltd | Professional & scientific | 2012 |
| Rawformstudios Ltd | Arts & recreation | 2025 |
| Raystede Centre Construction Limited | Construction | 2003 |
| Raystede Centre for Animal Welfare Limited(The) | Professional & scientific | 1964 |
| RBE Property Management Ltd | Real estate | 2025 |
| RC Auto Centre Limited | Transport & logistics | 2008 |
| RD Carpentry and Construction (Sussex) Ltd | Construction | 2026 |
| RDF Training Solutions Ltd | Information & communication | 2018 |
| RDH Commercials Ltd | Wholesale & retail | 2008 |
| RDH Garage Lewes Limited | Financial services | 2025 |
| Re-Assembly Ltd | Professional & scientific | 2023 |
| Reading Room Day Spa 2016 Limited | Other services | 2016 |
| Real Talk Counselling Limited | Health & social care | 2025 |
| Reality Zero One Limited | Manufacturing | 2017 |
| Really Quite Something Limited | Information & communication | 2014 |
| Really Real Ltd | Information & communication | 2024 |
| Recircle Tech Ltd | Wholesale & retail | 2025 |
| Red Consultants Limited | Information & communication | 1997 |
| Red FOX Thermal Ltd | Information & communication | 2026 |
| Red House Management Company Limited | Administrative & support | 1976 |
| Red Rocket Software and Design Ltd | Professional & scientific | 2012 |
| Redditch Services Limited | Professional & scientific | 2026 |
| Rednal Consulting Ltd | Information & communication | 2006 |
| Reforestation Limited | Health & social care | 2017 |
| Reid Apps Limited | Information & communication | 2024 |
| Remind Voice Ltd | Information & communication | 2025 |
| Renshaw Grove Limited | Professional & scientific | 2023 |
| Reshape Living Limited | Wholesale & retail | 2025 |
| Resonate Collective Ltd | Professional & scientific | 2021 |
| Resourcewerke Ltd | Professional & scientific | 2012 |
| Responsive Design Limited | Information & communication | 2011 |
| Review of Sussex Arts C.I.C. | Information & communication | 2021 |
| Revival Motor Sport Limited | Wholesale & retail | 2002 |
| Revive Medispa Limited | Other services | 2019 |
| Rezilience Ltd | Education | 2020 |
| Rhino Rigging Limited | Construction | 2006 |
| Richard's Cars & Minibuses Ltd | Transport & logistics | 2018 |
| Richardson Architecture Ltd | Professional & scientific | 2008 |
| Rikileaks Limited | Construction | 2025 |
| Rima 17 Real Estate Ltd | Households | 2012 |
| Ringmer Cafe & Bistro Ltd | Hospitality | 2023 |
| Ringmer Independent Care Ltd | Health & social care | 2024 |
| Ripe Village Stores | Wholesale & retail | 2012 |
| Riva Insurance Brokers Ltd | Financial services | 2010 |
| Rivercrest Limited | Construction | 1988 |
| Rivers Oram Publishers Limited | Information & communication | 2017 |
| RJ Cook Carpentry Ltd | Administrative & support | 2017 |
| Rjab Consulting Limited | Professional & scientific | 2015 |
| RJC Growth Ltd | Professional & scientific | 2024 |
| RJE Planning & Developments Limited | Construction | 2011 |
| Rjmf Investments Limited | Real estate | 2014 |
| Rjwc Ltd | Real estate | 2016 |
| RMH Building Services Limited | Construction | 2011 |
| Robin Stevenson Glulam Ltd | Construction | 2024 |
| Robyn Allpress Studio Ltd | Arts & recreation | 2025 |
| Rockethound Ltd | Information & communication | 2026 |
| Rockfelt Roofing Limited | Construction | 2017 |
| Rodmell House Lewes Limited | Professional & scientific | 1989 |
| Roger Dean Associates Limited | Arts & recreation | 2001 |
| RON Young (Motors) Limited | Wholesale & retail | 1985 |
| Root Projx Ltd | Information & communication | 2026 |
| Rose Wilson Ltd | Health & social care | 2024 |
| Rose Wire Limited | Manufacturing | 2024 |
| Rosemead Group Ltd | Administrative & support | 2024 |
| Rosewell Property Ltd | Real estate | 2022 |
| Rousham Engineering Limited | Arts & recreation | 2002 |
| Routes for Change CIC | Health & social care | 2019 |
| Rovert Sllew Limited | Financial services | 2012 |
| Rowan Business Solutions Ltd | Professional & scientific | 1991 |
| Rowson Consulting Limited | Professional & scientific | 2007 |
| RPJ Development Group Ltd | Construction | 2021 |
| RPJ Developments (Sussex) Ltd | Construction | 2021 |
| Rpurdie Ltd | Information & communication | 2018 |
| RR Autocare Limited | Wholesale & retail | 2014 |
| RR Motorsport Limited | Administrative & support | 2024 |
| RS Grill Direct Ltd | Wholesale & retail | 2020 |
| Rsaj Property Services Ltd | Construction | 2025 |
| Rubicon Children & Family Services Limited | Health & social care | 2009 |
| Rumalo Limited | Professional & scientific | 2011 |