| Appliedpath Education Limited | Information & communication | 2025 |
| Apply Quantum Limited | Professional & scientific | 2023 |
| Appola Desserts Ltd | Manufacturing | 2026 |
| Apposite CP II GP LLP | | 2015 |
| Apposite CP II LP | | 2015 |
| Apposite CP III GP LLP | | 2020 |
| Apposite CP III LP | | 2020 |
| Apposite CP1 (GP) Limited | Administrative & support | 2006 |
| Apposite CP1 LP | | 2006 |
| Apposite Growth I CP GP LLP | | 2024 |
| Apposite Healthcare Growth I CP LP | | 2026 |
| Appreactor LP | | 2016 |
| Approov Limited | Administrative & support | 2001 |
| Apps Centre LP | | 2014 |
| APPS2DATA (Holdings) Limited | Financial services | 2003 |
| Appsstudio Group LP | | 2016 |
| Apptrix Ltd | Information & communication | 2020 |
| Appus Studio LP | | 2015 |
| Apremont Limited | Real estate | 1992 |
| Aprent LP | | 2017 |
| Aprexim Group LP | | 2016 |
| Aprilcom LP | | 2017 |
| Apro Corporate LP | | 2016 |
| Aprom Alliance LP | | 2016 |
| Aproxi LP | | 2016 |
| Aprynzoloom Flow Control Limited | Information & communication | 2026 |
| APS Group (Scotland) Limited | Administrative & support | 2009 |
| Apter Ltd | Administrative & support | 2025 |
| Aptiq Works Limited | Information & communication | 2025 |
| Apus Corporation LP | | 2016 |
| APW Electrical Ltd | Construction | 2026 |
| APW Roofing and Roughcasting Ltd | Construction | 2025 |
| APZ Engineering Ltd | Professional & scientific | 2026 |
| AQ Prime Properties Limited | Real estate | 2025 |
| Aqa-Bargains Limited | Wholesale & retail | 2025 |
| Aqil Martial Arts Ltd | Manufacturing | 2026 |
| Aqrix IT Ltd | Information & communication | 2025 |
| Aqua & GAS Scotland Ltd | Construction | 2020 |
| Aqua Blast Scotland Ltd | Manufacturing | 2019 |
| Aqua People Consulting Ltd | Professional & scientific | 2020 |
| Aqua Perfecta LP | | 2020 |
| Aqua Power Ltd | Professional & scientific | 2020 |
| Aqua Property Services (Edin) Ltd | Construction | 2026 |
| Aqua Quip Scotland Ltd | Agriculture & fishing | 2020 |
| Aqua Taurus SP | | 2004 |
| Aquaclear SC Ltd | Water & waste | 2009 |
| Aquafredda LP | | 2015 |
| Aqualis Systems Ltd | Professional & scientific | 2025 |
| Aquamarine Bay Transit LP | | 2016 |
| Aquamoor Limited | Professional & scientific | 2015 |
| Aquanet Power UK Limited | Professional & scientific | 2017 |
| Aquaquantix Limited | Wholesale & retail | 2025 |
| Aquarius CXO Ltd | Professional & scientific | 2025 |
| Aquatic Learning Limited | Arts & recreation | 2003 |
| Aquatics Tradework LP | | 2016 |
| Aquaville Logistics LP | | 2014 |
| Aquclean Services (Scotland) Ltd | Administrative & support | 2025 |
| Aquil Alliance LP | | 2016 |
| AR Accountancy Services Scotland Limited | Professional & scientific | 2024 |
| AR Auto Sales Ltd | Wholesale & retail | 2023 |
| AR Coffee Retail Ltd | Manufacturing | 2014 |
| AR Dundas Limited | Administrative & support | 2006 |
| AR Equity Investment Ltd | Financial services | 2022 |
| AR One Security Ltd | Administrative & support | 2026 |
| AR Planning Solutions Ltd | Construction | 2012 |
| AR Projects SLP Limited Partnership | | 2019 |
| AR Properties Livingston Limited | Real estate | 2025 |
| AR SEO Consultant Ltd | Information & communication | 2025 |
| AR SGP Limited | Construction | 2019 |
| AR Solutions Group Ltd | Administrative & support | 2025 |
| AR Triangle Property GP Limited | Professional & scientific | 2019 |
| AR Triangle Property LP | | 2019 |
| AR28 Ltd | Health & social care | 2021 |
| AR7 Limited | Wholesale & retail | 2025 |
| ARA Capital LP | | 2017 |
| ARA Lets Ltd | Hospitality | 2014 |
| Arabella Group LP | | 2015 |
| Arabia Foods (Scotland) Limited | Wholesale & retail | 2019 |
| Arabianliving Ltd | Information & communication | 2025 |
| Araguaney Investments L.P. | | 2015 |
| Arakha Limited | Hospitality | 2023 |
| Aram Care Limited | Public administration | 2025 |
| Aramco Investco LP | | 2023 |
| Aranak LP | | 2016 |
| Aranci & Firth Properties Ltd | Administrative & support | 2021 |
| Araneth Limited | Information & communication | 2025 |
| Aratac Hockey Limited | Wholesale & retail | 1991 |
| Aravalli Alliance LP | | 2018 |
| Aray Trading Limited | Real estate | 2005 |
| Arazim Consulting Ltd | Professional & scientific | 2025 |
| ARB Edin Ltd | Hospitality | 2025 |
| Arba Investments & Properties Limited | Real estate | 2024 |
| Arbic Steel LP | | 2016 |
| Arbikie Distillery Green Hydrogen Limited | Professional & scientific | 2022 |
| Arbington Capital LP | | 2019 |
| Arbitrage Abroad LP | | 2016 |
| Arbitrage Project L.P. | | 2012 |
| Arbitration Centre | Public administration | 2011 |
| Arbol LP | | 2001 |
| Arboleda LP | | 2001 |