| BOB Arnold Limited | Real estate | 2023 |
| BOB the Builder Catering Limited | Hospitality | 2018 |
| Bobbin Heads Ltd | Professional & scientific | 2025 |
| Bobby Martins Investments Limited | Wholesale & retail | 2022 |
| Bobbys 354 Ltd | Wholesale & retail | 2025 |
| Bocc Ltd | Health & social care | 2021 |
| Bock Consultancy & Personnel Development Limited | Education | 2008 |
| Body Revive Fitness Ltd | Education | 2024 |
| Bodyrock Fitness UK Limited | Arts & recreation | 2010 |
| Bodysmart Physiotherapy LLP | | 2011 |
| Bohr Technology Ltd | Wholesale & retail | 2025 |
| Boiler Safe UK Ltd | Manufacturing | 2018 |
| Boldrise Estates Ltd | Real estate | 2025 |
| Boleyn Court Freehold (Redhill) Limited | Households | 2011 |
| Boli Auto UK Limited | Wholesale & retail | 2025 |
| Bollin Court (Brooklands) Management Limited | Households | 2001 |
| Bollington Mill Management Company Limited | Households | 1993 |
| Bolney Grange(Croydon)Management Company | Households | 1974 |
| Boman Solutions Limited | Information & communication | 2005 |
| Bomoko Estates Limited | Real estate | 2023 |
| Bomoko Sourcing Limited | Professional & scientific | 2023 |
| Bond House Management Company Limited | Households | 2017 |
| Bond Media Limited | Information & communication | 2004 |
| Bond Scale Ltd | Professional & scientific | 2023 |
| Bond Wealth Ltd | Financial services | 2013 |
| Bonds of Shirley Ltd | Wholesale & retail | 2022 |
| Bongbethiamendoza Limited | Administrative & support | 2022 |
| Bonheur Limited | Real estate | 2013 |
| Bonjour Campers Ltd | Administrative & support | 2025 |
| Bonnici Brothers Limited | Construction | 2022 |
| Bonsor House RTM Company Limited | Households | 2017 |
| Boomerangg Limited | Wholesale & retail | 2021 |
| Boomfields Ltd. | Hospitality | 2002 |
| Boomgrand Limited | Construction | 1991 |
| Boon Café CIC | Hospitality | 2024 |
| Boost My Maths Ltd | Education | 2025 |
| Booth Court (Bristol) Management Limited | Households | 2008 |
| Bootie Bling Limited | Wholesale & retail | 2015 |
| Booze Bros Limited | Wholesale & retail | 2022 |
| Boquetique Limited | Wholesale & retail | 2024 |
| Border County Properties Limited | Real estate | 1962 |
| Border Lodge Management Limited | Households | 1985 |
| Border Real Estate Ltd | Real estate | 2016 |
| Boring Code Ltd | Information & communication | 2019 |
| Boris Estate Ltd | Real estate | 2026 |
| Borlase Gardens Management Company Limited | Households | 2007 |
| Borlog Ltd | Professional & scientific | 2018 |
| Borough Green (Kent) Management Company Limited | Households | 2013 |
| Boryl Ltd | Professional & scientific | 2022 |
| BOS Cutz Ltd | Other services | 2025 |
| Bose Chicken Worldish Ltd | Hospitality | 2022 |
| Boshe Ltd | Wholesale & retail | 2025 |
| Bosmik Ltd | Health & social care | 2018 |
| Boss & Bloom Ltd | Other services | 2025 |
| Bossladyuk Ltd | Wholesale & retail | 2024 |
| Bossman Traders Ltd | Hospitality | 2025 |
| Both Sides Communications Ltd | Professional & scientific | 2018 |
| Bough Beech Court (Management) Limited | Households | 1978 |
| Bounce Motion Limited | Information & communication | 2017 |
| Bound & Gagged Limited | Arts & recreation | 2000 |
| Bourne Investments Limited | Real estate | 2008 |
| Bourns Court Freehold Limited | Households | 1992 |
| Bowers Mill Freehold Company Limited | Households | 2012 |
| Bowhay Lane Stores Limited | Wholesale & retail | 2012 |
| Bowland View Management Company Limited | Households | 2015 |
| Bowling Green Farmhouse Limited | Households | 2000 |
| Bowry Family Partnership LLP | | 2018 |
| Bowry Services Ltd | Professional & scientific | 2015 |
| Box & Burn Ltd | Information & communication | 2023 |
| Boxred Marketing Limited | Wholesale & retail | 2008 |
| Boxwood Court Management Ltd | Households | 2019 |
| Boyal Investments Limited | Real estate | 2025 |
| Boyd & Peters Limited | Real estate | 2017 |
| Boyden & Co.Limited | Wholesale & retail | 1925 |
| Boyden Investments Limited | Financial services | 2015 |
| BP Cutzz Ltd | Other services | 2025 |
| BP Holding Solutions Ltd | Financial services | 2025 |
| BP Prime Investments Limited | Real estate | 2017 |
| BPK Lettings Ltd | Real estate | 2022 |
| Bpone Solutions Ltd | Information & communication | 2025 |
| Bprop Ltd | Real estate | 2020 |
| BQS UK Trading Ltd | Wholesale & retail | 2024 |
| BR E1 Investments Limited | Real estate | 2025 |
| BR Technologies Limited | Wholesale & retail | 2014 |
| BR3 Consultancy Limited | Information & communication | 2024 |
| Brabham Court Worcester Park Limited | Households | 2002 |
| Brabourne Developments Limited | Real estate | 2000 |
| Brackenberry Limited | Administrative & support | 2021 |
| Brackenbury Electronics Limited | Manufacturing | 1991 |
| Brackenwood (Cranleigh) Management Company Limited | Households | 2000 |
| Bradeley Hall Farm Management Company Limited | Households | 2006 |
| Bradfield Ventures Limited | Wholesale & retail | 2025 |
| Bradgate Holdings and Development Group Ltd | Households | 2024 |
| Bradleys Retail Limited | Wholesale & retail | 2019 |
| Bradonpark Limited | Real estate | 1994 |
| Bradtower Limited | Administrative & support | 1986 |
| Bradu Logistics Ltd | Transport & logistics | 2024 |
| Bradwell Village Management Limited | Households | 1997 |
| Brady's Touch Ltd | Hospitality | 2025 |
| Braeburn House Management Company Limited | Real estate | 2018 |