| Agile Business Consultancy & Solutions Ltd | Information & communication | 2015 |
| Agmc Properties Limited | Real estate | 2023 |
| AGS Training Ltd | Other services | 2013 |
| Air Climate Solutions Limited | Energy | 2015 |
| Airius Destratification Solutions Limited | Real estate | 2001 |
| Aitken Developments Limited | Construction | 1993 |
| Aitken Holdings Limited | Real estate | 1985 |
| Aitkenhead Partnership | | 1984 |
| Aitkinson Aviation Ltd | Manufacturing | 2020 |
| Ajaco Engineering Limited | Professional & scientific | 2020 |
| Ajpropertylets Ltd | Real estate | 2026 |
| Akonstruct Ltd | Construction | 2020 |
| Akwaclean Ltd | Administrative & support | 2023 |
| Akwaclean PM Ltd | Administrative & support | 2025 |
| AL Williamson Ltd | Financial services | 2021 |
| Al's Property Scotland Ltd | Real estate | 2020 |
| Alan Gall Estate Agent Limited | Real estate | 2021 |
| Aland Cuts Ltd | Other services | 2025 |
| Alba Planning Consultants Limited | Professional & scientific | 1995 |
| Albion Environmental Trustees Limited | Extraterritorial | 2020 |
| Alcam Precision Engineering Limited | Professional & scientific | 2014 |
| Alcami DB Ltd | Construction | 2025 |
| Aldente Traders Ltd | Hospitality | 2024 |
| Alderbank Contractors Limited | Construction | 2002 |
| Alet-Trans LP | | 2014 |
| Alex Begg Group Limited | Manufacturing | 1949 |
| Alexander Dunlop Limited | Wholesale & retail | 2025 |
| Alexanders' SAW Mills Limited | Real estate | 1965 |
| Alishia Mackay Welding Limited | Manufacturing | 2024 |
| Alister Trade LP | | 2014 |
| ALL Hands on Earth Ltd | Wholesale & retail | 2023 |
| ALL Warriors Ltd | Arts & recreation | 2019 |
| Allah HOO Travels Limited | Administrative & support | 2022 |
| Allan & Daughter Ltd | Transport & logistics | 2025 |
| Allanreid Properties Ltd | Real estate | 2021 |
| Allanvale Land (Auchincruive) Limited | Construction | 2020 |
| Alloway Agencies | | 1999 |
| Alloway Capital Limited | Real estate | 2020 |
| Alloway Engineering Ltd | Professional & scientific | 2018 |
| Alloway Financial Limited | Financial services | 2016 |
| Alloway Healthcare Limited | Wholesale & retail | 2017 |
| Alloway Retail Limited | Administrative & support | 2005 |
| Alma Corporation LP | | 2014 |
| Alnajjar International Limited | Construction | 2026 |
| Alpha Electrical Fire & Security Ltd | Construction | 2018 |
| Alpha G Limited | Administrative & support | 2012 |
| Alpha Transmission and Distribution Ltd | Construction | 2024 |
| Alpino Consulting LP | | 2014 |
| Alpro Services Ltd | Real estate | 2018 |
| Altimus Corp. LP | | 2014 |
| Alveks Trade LP | | 2015 |
| Always Clean Windows Ltd | Administrative & support | 2021 |
| AM Service Stations Limited | Wholesale & retail | 2000 |
| AM2 SCO Limited | Hospitality | 2025 |
| Amac Rail Ltd | Professional & scientific | 2023 |
| Amanic Ltd | Real estate | 2022 |
| Amarantha LP | | 2014 |
| Amazingvanny Holding Enterprise Ltd | Wholesale & retail | 2025 |
| AMC Aria Holdings Limited | Real estate | 2016 |
| AMC Enterprises AYR Limited | Hospitality | 2018 |
| AMC Properties AYR Limited | Construction | 2024 |
| AMC Scotland Limited | Construction | 2023 |
| AMC Shopfitting Ltd | Construction | 2012 |
| American Candy & Drinks Ltd | Wholesale & retail | 2026 |
| American Candy AYR Ltd | Wholesale & retail | 2025 |
| Amir Solutions Ltd | Administrative & support | 2026 |
| Amiwill Ltd | Information & communication | 2007 |
| AML Bspoke Ltd | Administrative & support | 2025 |
| Ampco Engineering Limited | Manufacturing | 1990 |
| Ampmhotproperty Limited | Hospitality | 2013 |
| Amria K Limited | Health & social care | 2020 |
| AN MAC Property Ltd | Real estate | 2024 |
| Analog Trade LP | | 2014 |
| Anda Project Limited | Construction | 2025 |
| Andersson Dental Care Ltd. | Health & social care | 2010 |
| Andrew Doidge Consulting Ltd | Professional & scientific | 2023 |
| Andrew's Commercial Enterprises Limited | Real estate | 1982 |
| Andy Gilchrist Ltd | Professional & scientific | 2011 |
| Andy Mitchell Therapies Ltd | Health & social care | 2020 |
| Angeliny LP | | 2014 |
| Angelle Services Ltd | Real estate | 2012 |
| ANM Restaurant Limited | Hospitality | 2023 |
| Anne Crow Limited | Hospitality | 2013 |
| Ansh Strategies Ltd | Manufacturing | 2022 |
| Apeirogon Engineering Limited | Construction | 2022 |
| Apex AYR Ltd | Hospitality | 2021 |
| Apex Lifts Scotland Ltd | Professional & scientific | 2018 |
| Applied Advanced Acoustics Limited | Professional & scientific | 2023 |
| Aqua Vision Plumbing Ltd | Real estate | 2024 |
| Aquamotive Limited | Manufacturing | 2007 |
| Aquatron Properties Limited | Real estate | 2017 |
| Aranda Consult LP | | 2014 |
| Archer Dean Electrical Contractors Ltd | Construction | 2022 |
| Archlight Restoration Ltd | Wholesale & retail | 2025 |
| Archtag Limited | Professional & scientific | 1997 |
| Ardgowan Properties Ltd. | Health & social care | 2011 |
| Ardgowan Property Investment Limited | Real estate | 2025 |
| Ardison Corp. LP | | 2015 |
| ARE KAY Aviation Ltd | Manufacturing | 2026 |
| Aremo Scotland Limited | Wholesale & retail | 2024 |