| ATC (Heat) Ltd | Construction | 2013 |
| Atct Logistics Limited | Transport & logistics | 2014 |
| Atelier ABZ Ltd | Professional & scientific | 2023 |
| Atelier Cozum Sist VE Yapi Malz SAN TIC Limited | Wholesale & retail | 2020 |
| Atella Inter LP | | 2013 |
| Atexor Ltd. | Wholesale & retail | 2016 |
| Athena Appointments Limited | Other services | 2024 |
| Athena Companion Care Limited | Professional & scientific | 2025 |
| Athena Engineering and Design Limited | Professional & scientific | 2012 |
| Athena Exploration Limited | Mining & quarrying | 2013 |
| Athlete Limited | Wholesale & retail | 2018 |
| Athletic Performance Training and Education Ltd | Education | 2025 |
| Atholl Hotel UK Limited | Hospitality | 2025 |
| Atholl Scott Financial Services Limited | Financial services | 1988 |
| Atholl Scott Ltd | Professional & scientific | 2013 |
| Atholl Technical Solutions Limited | Mining & quarrying | 2007 |
| Atholls Limited | Administrative & support | 2007 |
| ATI Transfer Ltd | Transport & logistics | 2023 |
| Atichat&Aonann Limited | Hospitality | 2019 |
| Atkinson and Co Estates Limited | Real estate | 2025 |
| Atlantic Grey LP | | 2015 |
| Atlantic Ocean Adventure Ltd | Administrative & support | 2026 |
| Atlantic Resourcing Limited | Administrative & support | 1997 |
| Atlantic XL International Limited | Financial services | 2021 |
| Atlantis Bathroom and Kitchen Company (Aberdeen) Limited | Administrative & support | 2001 |
| Atlas 365 Services Ltd | Professional & scientific | 2023 |
| Atlas Fairweather Limited | Administrative & support | 2025 |
| Atlas Lifts and Services Limited | Other services | 2002 |
| Atmi Solutions Ltd | Information & communication | 2023 |
| Atmosphere Logistics Ltd | Wholesale & retail | 2018 |
| Atoms to Astronauts Ltd | Wholesale & retail | 2021 |
| ATR Equipment Solutions Limited | Administrative & support | 2026 |
| ATR Lifting Solutions Limited | Manufacturing | 1990 |
| ATR Overseas Limited | Administrative & support | 2007 |
| ATS Technology Services Ltd | Information & communication | 2024 |
| Atta Catering Ltd | Hospitality | 2024 |
| Attolo Limited | Hospitality | 2016 |
| Attu Island LP | | 2013 |
| Aubin Limited | Manufacturing | 1986 |
| Auchinderran Renewables Limited | Administrative & support | 2013 |
| Auchlee Farms | Professional & scientific | 1994 |
| Auchmill Road Limited | Real estate | 2010 |
| Auchterdeen Ltd. | Information & communication | 2005 |
| Audit Horizons Limited | Professional & scientific | 2013 |
| Audit Services North Ltd | Professional & scientific | 2023 |
| Augean North Sea Services Limited | Water & waste | 2012 |
| Augment.Eco Ltd | Administrative & support | 2020 |
| Augmentias Maritime & Offshore Engineering Ltd | Professional & scientific | 2013 |
| August Design Collaborative Ltd. | Professional & scientific | 2022 |
| AUK Energy Management Ltd | Mining & quarrying | 2006 |
| Auld Contractors Ltd | Construction | 2025 |
| Auldtoon Family Limited Partnership | | 2010 |
| Aupec Limited | Professional & scientific | 1997 |
| Aura Aberdeen Ltd | Real estate | 2025 |
| Aura Vector Limited | Wholesale & retail | 2026 |
| Aurabell Ltd | Wholesale & retail | 2025 |
| Aurelie Petitclerc Limited | Health & social care | 2022 |
| Auric CAD Solutions Ltd | Professional & scientific | 2014 |
| Aurora Ascending Ltd | Wholesale & retail | 2024 |
| Aurora Autistic Consulting Ltd | Other services | 2024 |
| Aurora BIT Consultancy Limited | Other services | 2006 |
| Aurora BLU Limited | Construction | 2024 |
| Aurora Energy Resources Limited | Mining & quarrying | 2008 |
| Aurora Energy Services Limited | Other services | 2022 |
| Aurora NMS Limited | Administrative & support | 2017 |
| Aurora Technical Solutions Limited | Information & communication | 2016 |
| Aurora Training Services Limited | Other services | 2015 |
| Aurum Dynamix Limited | Administrative & support | 2025 |
| Auryn Adornments Ltd | Wholesale & retail | 2023 |
| Authentic Psychology Services Ltd. | Health & social care | 2023 |
| Authentic Vietnamese Kitchen Ltd | Hospitality | 2024 |
| Autistic Flair CIC | Other services | 2022 |
| Auto Hygiene Car Wash Ltd | Administrative & support | 2024 |
| Auto Leisure Group Limited | Wholesale & retail | 2021 |
| Auto Lounge MOT & Service Centre Limited | Wholesale & retail | 2025 |
| Auto Spec Garage Ltd | Wholesale & retail | 2025 |
| Automasters Inverurie Ltd | Wholesale & retail | 2017 |
| Automation XL Limited | Information & communication | 2012 |
| Autonomous Digital Creatives Limited | Information & communication | 2016 |
| Autorehab Global Services Limited | Wholesale & retail | 2023 |
| Autospray (Aberdeen) Limited | Wholesale & retail | 2014 |
| Autovation Ltd | Wholesale & retail | 2022 |
| Auxilia Initiatives CIC | Wholesale & retail | 2022 |
| Auxiliary Business Services Limited | Administrative & support | 2025 |
| Auxilium Aberdeen Tax Limited | Professional & scientific | 2024 |
| AV Adaptions Ltd | Wholesale & retail | 2022 |
| AV One Solutions Ltd | Professional & scientific | 2016 |
| AVA Sunrise Ltd | Hospitality | 2023 |
| AVA Vision Ltd | Real estate | 2023 |
| Avalon Trading LP | | 2013 |
| Avark Ltd | Real estate | 2025 |
| Avenue Confidential | Other services | 1999 |
| Avera Bay LP | | 2013 |
| Aviatec Limited | Transport & logistics | 2013 |
| Aviation Logistics Group Limited | Transport & logistics | 2016 |
| Aviator Futures Limited | Administrative & support | 2018 |
| Avina Retail Ltd | Wholesale & retail | 2025 |
| Avitas Advisors Limited | Professional & scientific | 2015 |
| AVK 10 Care Limited | Health & social care | 2022 |
| AVK Dental Care Limited | Health & social care | 2013 |