| Boom Circus Ltd | Falmouth | 2018 |
| Boom Clap Play Forward CIC | Belfast | 2026 |
| Boom Dang Limited | Barrow-In-Furness | 2007 |
| Boom East Ltd | London | 2020 |
| Boom Fitness Ltd | Canterbury | 2014 |
| Boom Innovation Limited | Richmond | 2008 |
| Boom London Events Ltd | West Drayton | 2025 |
| Boom Tennis Coaching Limited | Warlingham | 2017 |
| Boom Theatre CIC | Camborne | 2023 |
| Boom! Inc | Bangor | 2016 |
| Boom! Production Services Ltd | Liverpool | 2019 |
| Boombastic Events Ltd | Northampton | 2015 |
| Boombox Golf Limited | Worcester | 2024 |
| Boomerang (FEC) Ltd | Bowerhill | 2024 |
| Boomerang Booth Limited | London | 2015 |
| Boomerang Family Entertainment Centre Ltd | Bowerhill | 2024 |
| Boomerang Holdings Ltd | Salisbury | 2009 |
| Boomerang Land & Properties Ltd | Melksham | 2009 |
| Boomerang Pro Fitness Ltd | Banbury | 2015 |
| Boomerang Stables Limited | Hungerford | 2017 |
| Boomers and Swingers Limited | Manchester | 2016 |
| Boomtown Events Limited | London | 2013 |
| Boomtown Festival UK Limited | London | 2011 |
| Boon Army Limited | Manchester | 2015 |
| Boonjan DK Limited | London | 2026 |
| Boost Fit Limited | Oxted | 2016 |
| Boost Fitness Limited | London | 2025 |
| Boost Hockey Academy Limited | Carrickfergus | 2022 |
| Boost Trampoline Parks (Leicester) Ltd | London | 2016 |
| Boost Trampoline Parks (Northampton) Ltd | London | 2016 |
| Boost Trampolining C.I.C. | Weston-Super-Mare | 2019 |
| Boost Your Body (Beeston) Ltd | Beeston | 2019 |
| Boost Your Body (Sharrow) Ltd | Beeston | 2019 |
| Boost Your Body Limited | Nottingham | 2017 |
| Booster Cushion Theatre Limited | Herts | 2003 |
| Boostpack Limited | | 2002 |
| Boot Camp Sheffield Ltd | Rotherham | 2021 |
| Boot LED Zeppelin Ltd | Swindon | 2006 |
| Boot UP Adventures Limited | Tarbock | 2024 |
| Boot UP the Network Ltd | London | 2026 |
| Bootcamp at Dalmally Ltd. | Dalmally | 2020 |
| Bootcamp Events Limited | Towcester | 2019 |
| Bootcamp Limited | Oxted | 2020 |
| Bootcamp Pilates Ltd | Borehamwood | 2010 |
| Bootcamp Retreats Limited | Crewe | 2018 |
| Bootcamp UK AB Ltd | Maidstone | 2022 |
| Bootcamp UK Reading Limited | Farnborough | 2019 |
| Bootcamps Nottingham Limited | Strelley | 2021 |
| Bootcampukbexleyheath Ltd | Maidstone | 2023 |
| Booth and Bear Ltd | Bury | 2026 |
| Boothferry Golf Club Limited | Goole | 2020 |
| Boothferry Park Ltd | Hull | 2014 |
| Booths and Bots Limited | Harlow | 2021 |
| BOOTHS4YOU Limited | East Kilbride | 2015 |
| Boothtube Limited | Crewe | 2016 |
| Bootle Bucks Inclusion FC CIC | Liverpool | 2023 |
| Bootle Community Hub CIC | Bootle | 2026 |
| Bootle Design Limited | Brighton | 2010 |
| Bootle Scrambles Club Limited | Millom | 1991 |
| Bootleg Eagles Live Ltd | Morpeth | 2024 |
| Boots & Beyond Ltd | Stockton-On-Tees | 2025 |
| Boots and Bark Ltd | Tring | 2021 |
| Boots and Beyond Football Ltd | Altrincham | 2025 |
| Boots on Adventures Ltd | Sittingbourne | 2021 |
| Bootworks Theatre Community Interest Company | Chichester | 2009 |
| Booty Bounce Limited | Melton Mowbray | 2023 |
| Booty Boutique Gym Ltd | Tarleton | 2017 |
| Booty Camp Ltd | Potters Bar | 2013 |
| Bootyfit Weight Loss Club Ltd | Watford | 2022 |
| Booze Productions Ltd | London | 2018 |
| Boozy Brushes Limited | Glasgow | 2024 |
| BOP Animations Ltd | Grimsby | 2019 |
| Bopbumpbounceevents Ltd | Cardiff | 2025 |
| Bopepa Limited | Addlestone | 2014 |
| Bopnbounce Ltd | Oldham | 2023 |
| Boppin' Bunnies Limited | Borehamwood | 2007 |
| Bopping Cat Ltd | London | 2006 |
| Bora Bora Entertainment Limited | London | 2025 |
| Bora Studio Limited | Tunbridge Wells | 2016 |
| Borba Tattoo Limited | Worcester | 2026 |
| Borde Hill Garden Limited | Haywards Heath | 1965 |
| Bordello the Musical UK Ltd | London | 2024 |
| Borden Sport Limited | Sittingbourne | 1999 |
| Border Arts Development C.I.C. | Jedburgh | 2016 |
| Border Beats Ltd | Carlisle | 2018 |
| Border Bingo Clubs Limited | Galashiels | 1999 |
| Border Counties Motor Racing Club Limited | Llandrindod Wells | 1996 |
| Border Crossings Company Limited | Middlesex | 1995 |
| Border Ecosse Car Club Limited (the) | Haddington | 1979 |
| Border Fine Art (West Sussex) Ltd | Chichester | 2024 |
| Border Motor Club (Lincs) Limited | Scunthorpe | 2004 |
| Border Performance Ltd | Narberth | 2026 |
| Border Pool and Gaming Ltd | Melrose | 2025 |
| Border Quad Trekking Limited | Welshpool | 2025 |
| Border Rythm Ltd | Carlisle | 2019 |
| Border Sportives Limited | Brampton | 2015 |
| Borderlands Tabletop Gamers CIC | Peebles | 2023 |
| Borderless Artists Ltd | London | 2025 |
| Borderless Atelier Ltd | Twickenham | 2026 |
| Borderless Beatz Ltd | London | 2026 |