| Blue Hearth Limited | Real estate | 2025 |
| Blue JAY Healthcare Ltd | Health & social care | 2021 |
| Blue OX Ltd | Wholesale & retail | 2024 |
| Blue Sky Accounting Solutions Limited | Professional & scientific | 2023 |
| Blue Sky Commercial Properties Limited | Real estate | 2025 |
| Blue Sky Engineering and Solutions Limited | Manufacturing | 2017 |
| Blue Sky Refrigeration Limited | Manufacturing | 2023 |
| Blue Snail Limited | Hospitality | 2017 |
| Blue Spruce Limited | Administrative & support | 2010 |
| Bluebell (Belchford) Limited | Hospitality | 2002 |
| Bluebells (Lincoln) Limited | Wholesale & retail | 2003 |
| Bluebird Fixings Limited | Manufacturing | 1988 |
| Bluecube Cloud Services Limited | Information & communication | 2008 |
| Bluesphere Television Limited | Professional & scientific | 2012 |
| Bluestrik Limited | Construction | 2025 |
| Bluevector Solutions Ltd | Professional & scientific | 2026 |
| Blythin & Brown Financial Solutions Ltd | Professional & scientific | 2020 |
| BM Business Consulting Limited | Other services | 2020 |
| BM Construction and Developments Ltd | Construction | 2024 |
| BM Contractors (Derby) Limited | Manufacturing | 2003 |
| BMF Training Ltd | Education | 2023 |
| BMR Haulage Limited | Administrative & support | 2016 |
| BN Lettings Limited | Real estate | 2007 |
| BN Reinstatement Solutions Ltd | Construction | 2025 |
| BNB Radiology Ltd | Health & social care | 2023 |
| Bnlvr Construction Limited | Construction | 2023 |
| Bnlvr Property Limited | Real estate | 2025 |
| Bnrm Landscaping and Services Ltd | Administrative & support | 2025 |
| Bo-Peep's Boutique Limited | Wholesale & retail | 2013 |
| BOB Soin Limited | Health & social care | 2009 |
| Boba Phoenix Ltd | Hospitality | 2024 |
| Boba Tea Lincoln Ltd | Hospitality | 2021 |
| Bobo Coffee Ltd | Manufacturing | 2025 |
| Bocias Ltd | Transport & logistics | 2017 |
| Body & Sole Limited | Health & social care | 2022 |
| Body CRE8 Ltd | Extraterritorial | 2021 |
| Body Lipo Lincoln Limited | Other services | 2023 |
| Body Restore Ltd | Wholesale & retail | 2023 |
| Bodyclose Holdings Limited | Financial services | 2019 |
| Bodytec Accident Repair Centre Limited | Wholesale & retail | 2003 |
| Bogdan Care Ltd | Health & social care | 2016 |
| Boleyn Containers Leasing Services Limited | Administrative & support | 2015 |
| Bolteton Medical Services Limited | Health & social care | 2021 |
| Bolton Coins and Medals Ltd | Other services | 2024 |
| Bomber Building Solutions Ltd | Construction | 2019 |
| Bond Housing Group (ABC Co-Living) Limited | Real estate | 2016 |
| Bond Housing Group (Bico) Ltd | Construction | 2018 |
| Bond Housing Group (Lincoln) Ltd | Construction | 2016 |
| Bond Housing Group (Living) Limited | Real estate | 2021 |
| Boneshakers Tattoos Limited | Wholesale & retail | 2015 |
| Bonlydes Ltd | Real estate | 2021 |
| Bonne Nature Ltd | Wholesale & retail | 2023 |
| Bonnetts Limited | Wholesale & retail | 2005 |
| Bonsor Locum Services Limited | Professional & scientific | 2018 |
| Booker Electrical Limited | Construction | 2003 |
| Bookminder Limited | Real estate | 2003 |
| Boop Property Limited | Administrative & support | 2024 |
| Booth Bricklaying Ltd. | Construction | 2021 |
| Booth Couriers Ltd | Transport & logistics | 2023 |
| Boothby Investments Limited | Real estate | 2004 |
| Boothby Property Consultancy Ltd | Real estate | 2020 |
| Booths Stonemasonry & Masonry Conservation Ltd | Manufacturing | 2023 |
| Bootleg Bars Limited | Hospitality | 2014 |
| Bordlan Holdings Limited | Other services | 2024 |
| Bordlan Limited | Water & waste | 2010 |
| Born Athlete Ltd | Arts & recreation | 2025 |
| Born to BE ME Ltd | Wholesale & retail | 2026 |
| Boss Construction Ltd | Construction | 2014 |
| Boss Developments (Lincoln) Ltd | Construction | 2016 |
| Boss Group Lincoln Ltd | Financial services | 2017 |
| Boss of Bosses Global Limited | Manufacturing | 2013 |
| Bostek Limited | Administrative & support | 2020 |
| Bostock Electrical Systems Ltd | Construction | 2024 |
| Boston Direct Management UK Ltd | Financial services | 2005 |
| Bosworth Bowden and Abbott Ltd. | Professional & scientific | 2001 |
| Botanical Elixir Ltd | Wholesale & retail | 2023 |
| Botanical Properties Ltd | Real estate | 2021 |
| Botfield Electrical Ltd | Construction | 2021 |
| Bots & Drones UK Ltd | Wholesale & retail | 2022 |
| Bottletop Holdings Limited | Financial services | 2018 |
| Boucher and Co. Property Ltd | Real estate | 2022 |
| Bougie and Bijou Ltd | Wholesale & retail | 2024 |
| Boulder Developments Limited | Manufacturing | 1997 |
| Boulder Holdings Limited | Real estate | 2018 |
| Boultham Wharf Ltd | Real estate | 2023 |
| Bouncetastic Lincoln Ltd | Arts & recreation | 2026 |
| Bouncetastic Ltd | Arts & recreation | 2020 |
| Boundary Construction Limited | Construction | 2016 |
| Boundary Garage (Lincoln) Limited | Wholesale & retail | 2017 |
| Boundary Lane Commercial Limited | Wholesale & retail | 2024 |
| Boundary Sports and Prestige Cars Limited | Administrative & support | 2018 |
| Bowec Limited | Real estate | 2026 |
| Bowel Surgery London Limited | Health & social care | 2012 |
| Bowelsurgeon Ltd | Health & social care | 2010 |
| Bower Property Limited | Real estate | 2006 |
| Bowkett and Sons Roofing Ltd | Construction | 2025 |
| Bowlby Tree Services & Care Ltd | Agriculture & fishing | 2024 |
| Bown & Co Holdings Ltd | Financial services | 2025 |
| Bowthorpe Construction Limited | Construction | 2019 |
| Bowthorpe Group Limited | Professional & scientific | 2018 |