| Bann Mechanical Ltd | Construction | 2019 |
| Bann Weavers Court Management Limited | Households | 1998 |
| Bannsaw Ltd | Manufacturing | 2021 |
| Bannside 2000 Limited | Health & social care | 2000 |
| Bannside Mill Property Limited | Real estate | 2019 |
| Bannview Dairy Farm Ltd | Agriculture & fishing | 2017 |
| Bannview Meadow Properties Limited | Real estate | 2014 |
| Banoge Properties Ltd | Real estate | 2020 |
| Barry Tennyson Electrical Ltd | Construction | 2019 |
| Barry Thompson & Co Accountants Ltd | Professional & scientific | 2013 |
| Basilico Restaurants Ltd | Hospitality | 2024 |
| Bathe Botanicals Ltd | Wholesale & retail | 2020 |
| Batit & Co. UK Ltd | Wholesale & retail | 2025 |
| Battlehill Holdings Ltd | Extraterritorial | 2024 |
| Bawnbua Foods NI Ltd | Manufacturing | 1984 |
| Bawnview Management Company Limited | Households | 2017 |
| BCJ Properties Ltd | Real estate | 2013 |
| BDM Amusements NI Limited | Arts & recreation | 2015 |
| BE - Studios Design Limited | Professional & scientific | 2019 |
| BE the Change (Tyrone) Ltd | Other services | 2025 |
| Beacon Ministries Limited | Health & social care | 2011 |
| Bean BKP Limited | Professional & scientific | 2023 |
| Bean Coffee Limited | Wholesale & retail | 2026 |
| Beattie Curtains Ltd | Wholesale & retail | 2026 |
| Beattie Furniture Ltd | Wholesale & retail | 2026 |
| Beau Bella Baby Ltd | Wholesale & retail | 2021 |
| Beaufort Collection Limited | Wholesale & retail | 2018 |
| Beaufort Interiors Limited | Wholesale & retail | 1984 |
| Beaumont Property Management Ltd | Households | 2015 |
| Beckett Assessors NI Ltd | Other services | 2022 |
| Bedeck Holdings Limited | Financial services | 2007 |
| Bedeck Limited | Wholesale & retail | 1989 |
| Bedrock International Limited | Real estate | 2015 |
| Bedrock Properties International Limited | Real estate | 2018 |
| Beech Grove Transport Ltd | Transport & logistics | 2026 |
| Beech Hill (NI) Ltd | Households | 2007 |
| Beech Tree Farm Wind Turbine Ltd | Energy | 2015 |
| Beeches Property Limited | | 2001 |
| Beechill Ltd | Professional & scientific | 2017 |
| Beechmount (Belfast) Limited | Construction | 2023 |
| Beechmount Trust Limited | Other services | 2001 |
| Begley & Co. Ltd | Professional & scientific | 2015 |
| Behavior Support Ltd | Health & social care | 2025 |
| Behind the Fold Ltd | Information & communication | 2020 |
| Beirne Racing Limited | Arts & recreation | 2023 |
| Bell Building Services Ltd | Construction | 2021 |
| Bell HV Solutions Ltd | Construction | 2025 |
| Bell Performance Planning Ltd | Professional & scientific | 2021 |
| Bell Performance Property Ltd | Real estate | 2023 |
| Bell's Mind Body Spirit Ltd | Health & social care | 2025 |
| Bellevue Service Station Ltd | Wholesale & retail | 2015 |
| Bellfield Park Management Limited | Households | 2026 |
| Belmont Strategy Limited | Professional & scientific | 2020 |
| Beloved Media Productions Ltd | Information & communication | 2024 |
| Belsize Wood Ltd | Construction | 2023 |
| BEN Beith Property Ltd | Real estate | 2024 |
| BEN Sergeant Tractors Ltd | Wholesale & retail | 2024 |
| Benettb Ltd | Transport & logistics | 2021 |
| Bennett's Bar Ltd | Hospitality | 2016 |
| Bespoke Property Solutions Ireland Limited | Real estate | 2022 |
| Best Body Repairs Ltd | Wholesale & retail | 2018 |
| Beta Asset Maintainance Ltd | Administrative & support | 2019 |
| Bethdylanjames Ltd | Information & communication | 2019 |
| Bethesda Fellowship | Other services | 2010 |
| Better Everyday Ltd | Administrative & support | 2021 |
| Better Health Physiotherapy Ltd | Health & social care | 2024 |
| Beverage Plastics Limited | Manufacturing | 1984 |
| Beyond AV Ltd | Arts & recreation | 2021 |
| Beyond Retail Group Ltd | Wholesale & retail | 2021 |
| BFM Active Limited | Wholesale & retail | 2020 |
| BHG Property Limited | Households | 2024 |
| BHJ Stores Ltd | Wholesale & retail | 2026 |
| Bigger Badder Better Ltd | Education | 2026 |
| Bimmerforged Ltd | Wholesale & retail | 2026 |
| BIO GAS 51 Ltd | Energy | 2016 |
| Biogas 74 (NI) Ltd | Energy | 2018 |
| Bioil Ltd | Wholesale & retail | 2003 |
| Birches Grove Management Ltd | Households | 2019 |
| Birchview Lodge Management Limited | Households | 2018 |
| Birdie Properties Ltd | Construction | 2014 |
| Bishops Green (Banbridge) Management Company Limited | Households | 2016 |
| Bishopscourt Kart Club Ltd | Arts & recreation | 1996 |
| BIZ Assist Limited | Professional & scientific | 2022 |
| BJ Decor Ltd | Construction | 2021 |
| Blackline Adventure Ltd | Wholesale & retail | 2022 |
| Blacklion Park Ltd | Construction | 2025 |
| Blacksessiagh Properties Ltd | Real estate | 2024 |
| Blackthorn Farm Limited | Agriculture & fishing | 2026 |
| Blackwater Manor Management Company Ltd | Households | 2017 |
| Blackwell Cottages Limited | Real estate | 2019 |
| Blackwell Country House Limited | Hospitality | 2023 |
| Blackwell House Limited | Hospitality | 2019 |
| Blade Shows Ltd | Wholesale & retail | 2024 |
| Bleary Farmers Hall Management Committee | Other services | 2012 |
| Bleary Finance Company Limited | Financial services | 2013 |
| Blinds Inc. Ltd | Construction | 2013 |
| BLINK1985 Ltd | Construction | 2026 |
| Bloomhill Services Limited | Other services | 2018 |
| BLU Hydrangea Ltd | Arts & recreation | 2020 |
| Blue Bell Realty Ltd | Real estate | 2025 |