| Reka Fish NET Ltd | Wholesale & retail | 2023 |
| Rekcool Ltd | Construction | 2026 |
| Relans Limited | Professional & scientific | 2010 |
| Reliable Networks Limited | Information & communication | 2005 |
| Relife Pharma Ltd | Manufacturing | 2023 |
| REM Glazing Ltd | Construction | 2016 |
| Remarkables Capital Ltd | Professional & scientific | 2018 |
| Remeck Limited | Health & social care | 2019 |
| Remedius Healthcare Ltd | Information & communication | 2025 |
| Remote Data Systems Ltd | Information & communication | 2020 |
| Remstrd Events Limited | Arts & recreation | 2025 |
| Remz Music Ltd | Arts & recreation | 2025 |
| REN - Chinese-British Cultural Exchange Association CIC | Other services | 2024 |
| Renaissance Residences Ltd | Real estate | 2024 |
| Renave Ltd | Health & social care | 2025 |
| Rendervibe Labs Ltd | Information & communication | 2026 |
| Renew Way Ltd | Construction | 2023 |
| Renewbath Master Restorers Limited | Other services | 2014 |
| Rent Wise Landlord Ltd | Real estate | 2025 |
| Rental Property Corporation Limited | Real estate | 2024 |
| Renteewild Ltd | Hospitality | 2026 |
| Renzoir Limited | Wholesale & retail | 2025 |
| Representation Upson Edwards Ltd | Other services | 2019 |
| Reputation Citadel Ltd | Professional & scientific | 2023 |
| Reroot London Ltd | Health & social care | 2026 |
| Resahost Ltd | Information & communication | 2022 |
| Rescued Clay Limited | Manufacturing | 2024 |
| Reserve Spree Ltd | Administrative & support | 2024 |
| Residential Care Services Limited | Health & social care | 1993 |
| Residential Property Ltd | Real estate | 2017 |
| Residualkey Ltd | Real estate | 2016 |
| Resolute EPP (Repp) Limited | Information & communication | 2014 |
| Resolve Guardian Limited | Administrative & support | 2015 |
| Retail UK Online Limited | Wholesale & retail | 2020 |
| Retailing Enterprises UK Limited | Wholesale & retail | 2026 |
| Revive Clinic (Bayswater) Limited | Health & social care | 2024 |
| Revive Clinic (Kensal Rise) Limited | Health & social care | 2025 |
| Revive Clinic Group Limited | Financial services | 2025 |
| Reviving Links CIC | Education | 2024 |
| Revmotion Ltd | Wholesale & retail | 2025 |
| Revvex Limited | Information & communication | 2026 |
| REWIR3D Limited | Other services | 2019 |
| Rewired Graphics Ltd | Professional & scientific | 2026 |
| Rewiring Ltd | Construction | 2021 |
| REX Hotel Holding Ltd | Financial services | 2023 |
| Rexi Cleaning Ltd | Administrative & support | 2023 |
| Rexumo Ltd | Information & communication | 2025 |
| REY Lettings & Co Ltd | Real estate | 2025 |
| RF UK Properties Ltd | Real estate | 2026 |
| RG Holidays Travel Limited | Administrative & support | 2023 |
| RG Intellectual Ltd | Wholesale & retail | 2020 |
| RG Travel Limited | Administrative & support | 2018 |
| Rgconnect Limited | Information & communication | 2023 |
| RGL Transport Ltd | Transport & logistics | 2022 |
| RGP Health Limited | Health & social care | 2009 |
| RGR Spices Limited | Wholesale & retail | 2026 |
| RH Construction Group Ltd | Hospitality | 2025 |
| RH Real Estate Ltd | Real estate | 2016 |
| RH Wellness Limited | Health & social care | 2021 |
| Rhari Ltd | Construction | 2026 |
| Rhinofierce Ltd | Administrative & support | 2025 |
| Rhodes Management & Consulting Services Ltd | Professional & scientific | 2021 |
| Rhondda Hospitality Ltd | Hospitality | 2023 |
| RHR Wellness Ltd | Manufacturing | 2024 |
| Rhythm & Move Limited | Information & communication | 2017 |
| Rhythm Riot Limited | Professional & scientific | 1997 |
| RIA Plumbing Services Ltd | Construction | 2024 |
| RIA V&M Ltd | Construction | 2024 |
| Riaan Enterprise Ltd | Construction | 2022 |
| Rianne Ltd | Wholesale & retail | 2025 |
| Riashx Limited | Wholesale & retail | 2023 |
| Ribeiro & Silva Property Limited | Real estate | 2023 |
| Ribetty Limited | Hospitality | 2022 |
| Rice 'N' Roll Kitchen Ltd | Wholesale & retail | 2022 |
| Rice and SO Ltd | Hospitality | 2025 |
| Rich - Riches Ltd | Wholesale & retail | 2010 |
| Rich Coming Limited | Hospitality | 2022 |
| Rich to Riches Limited | Wholesale & retail | 1997 |
| RICHARD651 Ltd | Construction | 2023 |
| Richstone London Ltd | Manufacturing | 2013 |
| Ricky Brady Plumbing and Heating Ltd | Construction | 2023 |
| Ridaan Holidays Limited | Administrative & support | 2023 |
| Riddhi Services Ltd | Wholesale & retail | 2019 |
| Riddish Consulting Ltd | Professional & scientific | 2018 |
| Ridedrop Ltd | Transport & logistics | 2026 |
| Rideit Motorcycles Ltd | Wholesale & retail | 2025 |
| Riders Cars Services Limited | Transport & logistics | 2023 |
| Ridewell Automotive Ltd | Transport & logistics | 2008 |
| Ridhi Infosec Ltd | Information & communication | 2024 |
| Ridinghood Transport Ltd | Transport & logistics | 2022 |
| Ridzy Enterprise Ltd | Wholesale & retail | 2023 |
| Rifai Chinese Ltd | Hospitality | 2026 |
| RIG Agency Ltd | Construction | 2021 |
| Rigel Care Group Limited | Health & social care | 2023 |
| Right Click Consultancy Ltd | Information & communication | 2016 |
| Right Home Estates Limited | Real estate | 2013 |
| Right Medicare Services Ltd | Health & social care | 2019 |
| Right Purpose Ltd | Other services | 2021 |
| Right to Manage-Avinya Patel Ltd | Administrative & support | 2009 |
| Rikdev Limited | Wholesale & retail | 2001 |