| R1 Electrical Limited | Administrative & support | 2010 |
| RAB Railways Limited | Construction | 2020 |
| RAC Electrical Services Limited | Construction | 2019 |
| Radar Cosmetics Ltd | Wholesale & retail | 2025 |
| Radiya's Kitchen Limited | Hospitality | 2024 |
| Radstone Holdings Ltd | Real estate | 2023 |
| RAE Elson Limited | Real estate | 2023 |
| RAE Property Services Ltd | Construction | 2021 |
| Raffeni Limited | Real estate | 2024 |
| Raffle Boys Limited | Administrative & support | 2024 |
| Raglan Woolwich Ltd | Hospitality | 2025 |
| Raico Recruitment Limited | Administrative & support | 2025 |
| Railec Limited | Construction | 2021 |
| Raileng Ltd | Construction | 2025 |
| Rainham Aggregates Limited | Water & waste | 2022 |
| Rainmade (UK) Limited | Information & communication | 2021 |
| Ralco Plastering Services Limited | Construction | 2020 |
| Ralco Services Limited | Construction | 2018 |
| Ralph Collier Limited | Construction | 2010 |
| Ramos Properties Limited | Real estate | 2019 |
| Rams Engineering Limited | Professional & scientific | 2009 |
| Ramsier Associates Limited | Administrative & support | 2007 |
| Rankdent Ltd. | Professional & scientific | 2017 |
| Rann Homes Limited | Real estate | 2025 |
| Rashid's Rapid Repairs Limited | Other services | 2025 |
| Rashmit Properties Ltd | Real estate | 2023 |
| Raslin Consulting Limited | Professional & scientific | 2021 |
| RAT & Mouse Ltd | Real estate | 2026 |
| Raven Promotions Limited | Administrative & support | 2001 |
| Raven's HOE Management Sidcup Ltd. | Households | 2016 |
| Ravspeed Ltd | Financial services | 2015 |
| RAW Electrical Services Limited | Construction | 2020 |
| RAY Heath Design Limited | Administrative & support | 2012 |
| Rays Tanning Limited | Other services | 2013 |
| Raywin Services Ltd | Construction | 2020 |
| RB Streetwise Law Ltd | Professional & scientific | 2023 |
| RBH UK Holdings Ltd | Other services | 2021 |
| RC Car Wash Limited | Professional & scientific | 2017 |
| RCR Partnership Limited | Administrative & support | 2013 |
| RD Controls Ltd | Professional & scientific | 2023 |
| Rdpb Limited | Financial services | 2009 |
| Rdrm Property & Builders Ltd | Real estate | 2025 |
| Read Group Limited | Professional & scientific | 2026 |
| Reads Building Services Limited | Construction | 2003 |
| Ready Cocktails Limited | Administrative & support | 2025 |
| Real Estate Analysts Limited | Real estate | 2019 |
| Realco Building Ltd | Construction | 2020 |
| Realising Resilience Limited | Professional & scientific | 2023 |
| Rebekah Manning Limited | Administrative & support | 2017 |
| REC Technical Services Limited | Construction | 2020 |
| Recado Project Management Limited | Professional & scientific | 2025 |
| Recruiterfit Limited | Professional & scientific | 2016 |
| Red & White Construction Limited | Construction | 2020 |
| Red Barber Limited | Administrative & support | 2022 |
| Red Hand Gang Limited | Administrative & support | 2013 |
| Red Jelly Media Limited | Information & communication | 2016 |
| Red OX IT Limited | Information & communication | 2017 |
| Redd Wolf Ltd | Arts & recreation | 2025 |
| Redding + Limited | Professional & scientific | 2015 |
| Redloh Limited | Professional & scientific | 2003 |
| Redmond Roofing Contractors Limited | Construction | 2005 |
| Redtech Consultants Limited | Administrative & support | 2003 |
| Redwood Close (Sidcup) Management Company Ltd | Households | 2017 |
| Reel Mowers Ltd | Administrative & support | 2013 |
| Reel Revolution Ltd | Information & communication | 2025 |
| Reflections Print Lamination Limited | Manufacturing | 1993 |
| Reflexions Fight Camp Limited | Arts & recreation | 2022 |
| Reflexions Gym and Personal Training Limited | Arts & recreation | 2022 |
| Reflexions Gym Limited | Arts & recreation | 2013 |
| Refresh Building Ltd | Construction | 2012 |
| Reftek Limited | Construction | 2022 |
| Regency Waste Disposal Limited | Professional & scientific | 1985 |
| Regent Street Accountants Limited | Professional & scientific | 2024 |
| Reisen Bangladesh Ltd | Wholesale & retail | 2025 |
| Rejuvenate Aesthetic Ltd | Other services | 2013 |
| Relativity Software Limited | Information & communication | 2017 |
| Relax Tax Limited | Professional & scientific | 2007 |
| Relentless Martial Arts Limited | Education | 2024 |
| Reliance Automotive Ltd | Wholesale & retail | 2021 |
| Relyable Limited | Professional & scientific | 2007 |
| REM Training Limited | Administrative & support | 2019 |
| Remmington White Limited | Administrative & support | 2010 |
| Renewable Energy Incentives Limited | Construction | 2010 |
| Renoglaze Ltd | Construction | 2022 |
| Renovations B a Limited | Construction | 2017 |
| Rentayard Ltd | Real estate | 2020 |
| Renu Health Care Ltd | Health & social care | 2022 |
| Repair and Reuse Hub CIC | Other services | 2026 |
| Repco Support Limited | Real estate | 2008 |
| Republica DE LA Tapa (Bexley) Limited | Hospitality | 2022 |
| Republica DE LA Tapa (Mill ROW) Limited | Hospitality | 2025 |
| Republica DE LA Tapa (Sidcup) Limited | Other services | 2024 |
| Reset Electrical Services Limited | Construction | 2020 |
| Resilient Rehab Ltd | Health & social care | 2020 |
| Resknow Limited | Professional & scientific | 2014 |
| Resolute Support Services Ltd | Administrative & support | 2008 |
| Resolven UK Ltd | Professional & scientific | 2013 |
| Resonance Language Consultancy Ltd | Administrative & support | 2022 |
| Resource Development (UK) Ltd | Administrative & support | 1994 |
| Resourceful Media Ltd | Professional & scientific | 2013 |