| 1 Stop Wheel Repair Ltd | Wholesale & retail | 2022 |
| 21 Omnicare Ltd | Wholesale & retail | 2021 |
| 21TRAINING Limited | Education | 2021 |
| 360 Property Ireland Ltd | Real estate | 2023 |
| 3JRM Ltd | Administrative & support | 2018 |
| A & C Components Strabane Ltd | Wholesale & retail | 2016 |
| A&F NI Holdings Ltd | Financial services | 2021 |
| A&L Agricultural Ltd | Agriculture & fishing | 2025 |
| A&L Tyres (Strabane) Ltd | Wholesale & retail | 2021 |
| A. S. Ballantine Limited | Mining & quarrying | 1977 |
| A1 Flat Roofing Services Ltd | Construction | 2019 |
| A1 Property and Investments Ltd | Real estate | 2026 |
| AA Construction Projects Ltd | Construction | 2020 |
| Abercorn Cottage Management Limited | Real estate | 2005 |
| Abertay Lettings Ltd | Real estate | 2023 |
| Abologan Consulting Ltd | Professional & scientific | 2017 |
| ABU Dhabi Management Ltd | Real estate | 2022 |
| ADB Water Services Ltd | Construction | 2024 |
| Adria 2 Limited | Manufacturing | 2015 |
| AER Travel Limited | Hospitality | 2025 |
| AG Car Sales Limited | Wholesale & retail | 2017 |
| AGH Energy Limited | Energy | 2013 |
| AGL Partners Ltd | Professional & scientific | 2014 |
| AGP Groundwork Ltd | Construction | 2025 |
| Agri FIX NI Ltd | Manufacturing | 2025 |
| Agri Plant Sales (N.I.) Ltd | Wholesale & retail | 2023 |
| Ailish Danta Whispers Ltd | Information & communication | 2025 |
| Airmext Limited | Wholesale & retail | 2025 |
| AJ Britton Contracts Ltd | Construction | 2003 |
| AJR Construction Ltd | Construction | 2014 |
| Allanbet Limited | Wholesale & retail | 2024 |
| Anycarpart Ltd | Wholesale & retail | 2017 |
| AQ Engineering Ltd | Construction | 2013 |
| Arbantis Ltd | Wholesale & retail | 2017 |
| Ardstraw Quarries Ltd | Mining & quarrying | 2011 |
| Ares Tekke Ltd | Other services | 2025 |
| Arkle Construction Ltd | Construction | 2015 |
| Armada International Ltd | Wholesale & retail | 2026 |
| Artio Skincare LLP | | 2019 |
| ASG NW Limited | Hospitality | 2014 |
| ASH Property & Management Ltd | Construction | 2025 |
| ASH Tech Futures Ltd | Wholesale & retail | 2019 |
| Atcheson Properties (NI) Limited | Real estate | 2017 |
| Atlantic Way Campers Ltd | Administrative & support | 2025 |
| Atlantic Way Contracts Limited | Construction | 2023 |
| Aughabrack & District Community Association | Arts & recreation | 2004 |
| Autohaul Logistics Ltd | Transport & logistics | 2025 |
| AWO Mechanical Ltd | Construction | 2025 |
| B&B Bakes Ltd | Wholesale & retail | 2025 |
| B.M.C. Security Systems (N.I.) Limited | Construction | 1990 |
| Backfence Catering Ltd | Hospitality | 2017 |
| Backfence Trading Ltd | Hospitality | 2016 |
| Badko Ltd | Construction | 2011 |
| Balance Life Ltd | Health & social care | 2021 |
| Balcon Construction Limited | Construction | 2012 |
| Ballinacross Farms Ltd | Agriculture & fishing | 2013 |
| Ballyfatton Plant Limited | Construction | 2015 |
| Ballyheather Engineering Ltd | Professional & scientific | 2023 |
| Ballymore Farm Pet Foods Ltd | Manufacturing | 2014 |
| Ballyskeagh Stables Limited | Agriculture & fishing | 2015 |
| Barr Bros Painting Limited | Construction | 2014 |
| Barron Livestock Limited | Wholesale & retail | 2020 |
| Barrontop Farm Limited | Arts & recreation | 2013 |
| BC Engineering Ltd | Construction | 2018 |
| Bcedf Ltd | Wholesale & retail | 2020 |
| Beanpole Digital Limited | Professional & scientific | 2023 |
| Bearney Farms Limited | Agriculture & fishing | 2021 |
| Bearney Nurseries Ltd | Wholesale & retail | 2024 |
| Bejeweled @ Soul Strabane Ltd | Wholesale & retail | 2012 |
| Benchmark Traffic Management Ltd | Professional & scientific | 2020 |
| Better Utilities NI Ltd | Construction | 2020 |
| Bhaird Ltd | Construction | 2024 |
| BHB Property Solutions Ltd | Real estate | 2025 |
| Billie Mccormack Ltd | Other services | 2024 |
| Bistro Twentyone Ltd | Hospitality | 2023 |
| BL Coffee Ltd | Hospitality | 2025 |
| Blades Strabane Ltd | Other services | 2025 |
| BLU Chem Ltd | Manufacturing | 2017 |
| Blue Pebble Associates Ltd | Financial services | 2023 |
| BMC Consulting Limited | Professional & scientific | 2026 |
| BMK Contracts Ltd | Construction | 2012 |
| Boewood Ltd | Real estate | 2025 |
| Boilerfix Limited | Manufacturing | 2005 |
| Bonjour Developments Ltd | Construction | 2017 |
| Border Scaffolding (NI) Ltd | Construction | 2026 |
| Boulder Investments Ltd | Real estate | 2021 |
| Boyd Anderson Investments Limited | Professional & scientific | 2013 |
| BR Mechanical Pipework Limited | Construction | 2024 |
| Bracken Hill Management Company Limited | Households | 2019 |
| Bradmiller Ltd | Transport & logistics | 2010 |
| Bready & District Ulster-Scots Development Association | Arts & recreation | 2003 |
| Breen Air Ltd | Energy | 2017 |
| Breen Properties Limited | Real estate | 2004 |
| Brennan Building & Construction Ltd | Construction | 2019 |
| Breslin Hospitality Ltd | Hospitality | 2019 |
| Brian Mcgilloway Ltd | Arts & recreation | 2016 |
| Brooke Hairdressing Ltd | Other services | 2012 |
| Brooks Consult Ltd | Wholesale & retail | 2023 |
| Browne Power Ltd | Energy | 2011 |
| Building Services Sion Limited | Construction | 2017 |