| Equinox Bishopsgate Limited | London | 2017 |
| Equinox Event Management Limited | London | 2021 |
| Equinox Fitness Holdings UK Limited | London | 2016 |
| Equinox Kensington Limited | London | 2011 |
| Equinox Padel Ltd | Newark | 2026 |
| Equinox Physiotherapy Partnership Limited | Llanelli | 2011 |
| EQUINOX24 Limited | Loughborough | 2014 |
| Equinties Limited | Braintree | 2022 |
| Equip Fitness Ltd | Belfast | 2017 |
| Equip Outdoor Consultancy Ltd | Kendal | 2013 |
| Equip Sports C.I.C. | Hull | 2024 |
| Equipilates Limited | Derby | 2012 |
| Equipoise Health & Fitness Limited | Pinner | 2005 |
| Equipoise Reformer Pilates Limited | Leeds | 2026 |
| Equipoise Studio Limited | Leeds | 2026 |
| Equipoise Wellness Limited | London | 2025 |
| Equiprep Limited | Devizes | 2018 |
| Equitable Riding Academy Limited | Dorking | 2023 |
| Equitation Academy Ltd | Preston | 2024 |
| Equiv Ltd | Glasgow | 2026 |
| Equivalent Experience CIC | London | 2025 |
| Equivents UK Ltd | Southwold | 2015 |
| Equn Ltd | London | 2025 |
| EQUO3 Limited | Aylesbury | 2015 |
| Equus Bloodstock Services Limited | Newbury | 2013 |
| Equus Equestrian Centres Limited | Epsom | 1985 |
| Equus Highland Limited | Forres | 2023 |
| ER Digital Ltd | London | 2026 |
| ER Productions Ltd | Burgess Hill | 2025 |
| ER Worldwide Co., Ltd | Uxbridge | 2020 |
| Er-Hb Ltd | Harrow | 2025 |
| Er-Pt Ltd | Harrow | 2023 |
| ER1 Promotions Ltd | Leeds | 2020 |
| ERA Adventures Ltd | Wadebridge | 2009 |
| ERA Group Global Ltd | London | 2024 |
| ERA Interpretations Limited | Westgate-On-Sea | 2024 |
| ERA Leisure 4 Limited | Nottingham | 2014 |
| ERA Music Ltd | Derry | 2019 |
| ERA Reformer Pilates Ltd | Glasgow | 2025 |
| ERA Show Ltd | Cleckheaton | 2020 |
| ERA Theatre Ltd | London | 2025 |
| ERA Theatrical Productions Ltd | Crewe | 2024 |
| Era-Fit Ltd | Ivybridge | 2015 |
| Erah X Akiya Ltd | London | 2023 |
| Eram Limited | Chorley | 2017 |
| Erami Ltd | Cheltenham | 2026 |
| Erased Tapes Music Publishing Limited | London | 2011 |
| Erased Tapes Records Limited | London | 2011 |
| Erasmus Darwin Trading Limited | Lichfield | 2012 |
| Erato Record Classics Limited | London | 1986 |
| Eray Limited | Herne Bay | 2019 |
| ERB Fitness Ltd | Southampton | 2020 |
| Erbfmusic Limited | Cheadle | 2021 |
| Erbium Records Ltd | Bromsgrove | 2020 |
| ERD Productions Limited | London | 2020 |
| Erddig Songs Limited | London | 2007 |
| Erebus Lifestyle Ltd | Ballynahinch | 2021 |
| Ereira Limited | York | 2015 |
| Eremos Ecotourism Ltd | Leek | 2025 |
| Erena Community Sports Club C.I.C. | London | 2024 |
| Erena Sports Limited | Dalkeith | 2023 |
| Erenmoor Studios Ltd | London | 2022 |
| Erewash Indoor Bowling Club Limited | Long Eaton | 1982 |
| Erewash Indoor Bowls Centre | Long Eaton | 2015 |
| Erewash Partnership (Events) Limited | Ilkeston | 2018 |
| Erewash Valley Golf Club Limited | Ilkeston | 1910 |
| Erewash Valley Gymnastics Club Ltd | Ilkeston | 2013 |
| Erfj Music Ltd | Glasgow | 2024 |
| Ergo SUM Games Limited | Swinderby | 2013 |
| Ergon Theatre Ltd | Manchester | 2020 |
| Ergshoot Ltd | London | 2025 |
| Eric and Salome Estorick Foundation | London | 1995 |
| Eric Boat (Music) Limited | London | 1980 |
| Eric Chappell Productions Limited | Grantham | 1978 |
| Eric England Limited | Chingford | 2019 |
| Eric Glass Limited | London | 1953 |
| Eric Kuhn Productions Ltd | London | 2024 |
| Eric Longa Ltd | London | 2022 |
| Eric Steele Coaching Services Limited | Ashbourne | 2006 |
| Eric's Productions Limited | St Agnes | 2011 |
| Erica Armistead Ltd | Leiston | 2015 |
| Erica Gough Ltd | London | 2026 |
| Erica Stubbs Ltd | Margate | 2025 |
| Ericoarts Ltd | Edinburgh | 2025 |
| Ericom.S.L CIC | London | 2024 |
| Eridge Park Events Limited | London | 2001 |
| Erik Artist Ltd | London | 2025 |
| Erik Wilson Limited | London | 2006 |
| Erika Dance Ltd | London | 2025 |
| Erika James Limited | St John'S Wood | 2018 |
| Erin Aniker Ltd | Ilford | 2016 |
| Erin Cuthbert Limited | Brierley Hill | 2021 |
| Erin Go Bragh Development Association Limited | Erdington | 2005 |
| Erin Lawlor Studio Ltd | Stanmore | 2022 |
| Eriswell Lodge Limited | Brandon | 2014 |
| Erith & Belvedere Football Club Limited | Orpington | 1952 |
| Erith & Woolwich Kabaddi Club | Orpington | 2009 |
| Erith & Woolwich Kabadi Club (B) Ltd | Ilford | 2025 |
| Erith and Belvedere Community Football Club Limited | Dartford | 2023 |
| Erith Playhouse Limited | Kent | 1974 |