| Bakescourier Ltd | Transport & logistics | 2026 |
| Baking and Catering by Nirvana Ltd | Manufacturing | 2018 |
| Bakitapano Ltd | Wholesale & retail | 2026 |
| Bakro Sustainable Transport Limited | Transport & logistics | 2012 |
| Bakshi G Limited | Real estate | 2025 |
| Bal's Bobbles Limited | Wholesale & retail | 2022 |
| Balady Holdings Ltd | Hospitality | 2025 |
| Balady Trades Ltd | Hospitality | 2025 |
| Balance Batteries Ltd | Professional & scientific | 2020 |
| Balance Design (UK) Limited | Administrative & support | 2009 |
| Balance Leisure Limited | Arts & recreation | 2019 |
| Balance: Inspired Living Ltd | Real estate | 2024 |
| Balanced Lettings Limited | Real estate | 2025 |
| Baldmin Projects & ENG Maintenance Ltd | Manufacturing | 2024 |
| Baleday Ltd | Professional & scientific | 2010 |
| Balfe Consultants Limited | Professional & scientific | 2012 |
| Balholm Management Company Limited | Households | 2022 |
| Ball Events Community Hub CIC | Education | 2025 |
| Ballers Haulage Ltd | Transport & logistics | 2025 |
| Ballestra Advice Ltd | Financial services | 2021 |
| Balliamo Limited | Professional & scientific | 2010 |
| Ballinger Investments Limited | Information & communication | 2015 |
| Ballinger Properties Limited | Real estate | 2018 |
| Balloons & More Ltd | Wholesale & retail | 2021 |
| Balloony Events Limited | Other services | 2019 |
| Balloonytyphoony Ltd | Arts & recreation | 2024 |
| Ballou Findings Limited | Wholesale & retail | 1988 |
| Ballyduff Plant Sales Limited | Wholesale & retail | 1996 |
| Balm Medical Ltd | Professional & scientific | 2022 |
| Balman Holding UK Ltd | Financial services | 2021 |
| Balmoral Horton Limited | Construction | 2018 |
| Balt Consulting Limited | Professional & scientific | 2024 |
| Baltelecom Ltd | Information & communication | 2021 |
| Baltled UK Limited | Wholesale & retail | 2023 |
| Balvae & Company UK Limited | Information & communication | 2022 |
| Bamboo Bookkeeping Services Limited | Professional & scientific | 2018 |
| Bamboo Cottage Limited | Hospitality | 2024 |
| Bamboo Nails 27 Ltd | Other services | 2023 |
| Bamboo Street MK Limited | Hospitality | 2025 |
| Bamdation Software Ltd | Information & communication | 2022 |
| Bamyqa Limited | Real estate | 2022 |
| Banaf Ltd | Information & communication | 2023 |
| Banamwinji Limited | Health & social care | 2015 |
| Banana 88 Limited | Professional & scientific | 2019 |
| Banana Chauffeur Ltd | Transport & logistics | 2016 |
| Banana Moon Media Group Ltd | Information & communication | 2025 |
| Bancroft Meeting Place | Education | 1987 |
| Bandsky Ltd | Water & waste | 2026 |
| Banik Corp. UK Limited | Professional & scientific | 2012 |
| Banirmal Consultancy Limited | Information & communication | 2025 |
| Banishahi Estates Limited | Construction | 2021 |
| Bank Court Mews Limited | Real estate | 2005 |
| Banks Electrical MK Ltd | Construction | 2023 |
| Bankside LEY Management Company Limited | Households | 1995 |
| Bann Sakunee Thai Food Ltd | Hospitality | 2018 |
| Bansons Couriers Ltd | Transport & logistics | 2021 |
| Bantegra Ltd. | Information & communication | 2009 |
| Banuri Group Ltd | Health & social care | 2023 |
| Banwaitt Holdings Limited | Professional & scientific | 2019 |
| BAO SUI GUO Ltd. | Wholesale & retail | 2025 |
| Baobab & Butter Ltd | Other services | 2025 |
| Baobab Tribe Limited | Health & social care | 2020 |
| Bapha Ltd | Transport & logistics | 2021 |
| Baptiste Interiors Ltd | Construction | 2020 |
| Bar Bollywood Ltd | Arts & recreation | 2023 |
| Baraka (MK) Ltd | Wholesale & retail | 2019 |
| Baraka and Neema Enterprise Limited | Real estate | 2021 |
| Baraka and Neema Investments Ltd | Real estate | 2018 |
| Baraka Investment MK Limited | Hospitality | 2025 |
| Barakah&Balance Ltd | Professional & scientific | 2025 |
| Barbatim Laboratories Limited | Other services | 2019 |
| Barbel Business Solutions Ltd | Professional & scientific | 2016 |
| Barcvolt Ltd | Construction | 2025 |
| Bardon 222 Limited | Information & communication | 2004 |
| Bare Farm Management Company Limited | Households | 2010 |
| Barea Ltd | Information & communication | 2026 |
| Barefoot MAN Ltd | Extraterritorial | 2023 |
| Barefoot Sport Allies Ltd | Information & communication | 2014 |
| Bargains Hunters Ltd | Wholesale & retail | 2024 |
| Bargainsdirectmk Ltd | Wholesale & retail | 2023 |
| Barglowski Ltd | Construction | 2023 |
| Bariah Property Ltd | Real estate | 2017 |
| Bark & Protect Limited | Administrative & support | 2018 |
| Barkberry Yard Daycare & Grooming Academy Limited | Other services | 2022 |
| Barkberry Yard Ltd | Other services | 2020 |
| Barkley Fenn Consulting Ltd | Administrative & support | 2025 |
| Barkley Fenn Training and Consulting Limited | Education | 2020 |
| Barkomm Ltd | Wholesale & retail | 2016 |
| Barley & Bloom Trading Co. Limited | Wholesale & retail | 2025 |
| Barley Croft Flats Management (NO.1) Limited | Households | 1990 |
| Barley Grange (Dagnall) Management Company Limited | Households | 2009 |
| Barmi Prestige Construction Ltd | Construction | 2024 |
| Barna Trans Limited | Transport & logistics | 2020 |
| Barnaby Services Ltd | Construction | 2025 |
| Barneco Ltd | Other services | 2016 |
| Barnes Electrical MK Ltd | Construction | 2026 |
| Barnes Residential Investments & Lettings Limited | Real estate | 2018 |
| Barney Payne Education Consultancy Limited | Education | 2005 |
| Barnyard Estates Ltd | Real estate | 2025 |
| Barnyard Property Construction Ltd | Construction | 2023 |