| Ab Hot Cars Oy | Wholesale & retail | 1989 |
| Ab Ingenjörsbyrå Soft Engineering Insinööritoimisto Oy | Information & communication | 1994 |
| Ab Jokefa Oy | Administrative & support | 2014 |
| Ab K.I.S. Capital Oy | Professional & scientific | 1988 |
| Ab Kvhell Oy | Hospitality | 2010 |
| Ab Labyrinth Books Oy | Wholesale & retail | 1975 |
| Ab Lajban Oy | Health & social care | 2011 |
| Ab Local Rent Finland Oy | Administrative & support | 2026 |
| Ab Lytz Invest Oy | Real estate | 1996 |
| Ab M & D Trading Oy | Wholesale & retail | 2015 |
| Ab MBECO Oy | Professional & scientific | 2023 |
| Ab Mamelo Oy | Professional & scientific | 2024 |
| Ab Marcus Svartbäck Oy | Health & social care | 2007 |
| Ab McYnen Oy | Professional & scientific | 1987 |
| Ab Mer Music Oy | Professional & scientific | 2000 |
| Ab Mikael Hakala Oy | Wholesale & retail | 2025 |
| Ab N&M Comfort Consulting Oy | Professional & scientific | 2007 |
| Ab Nebulosa Oy | Manufacturing | 2008 |
| Ab OCS - Oil Company Scandinavia Ltd | Wholesale & retail | 1992 |
| Ab Opifex Novo Oy | Health & social care | 1993 |
| Ab Oskar Haglund Oy | Transport & logistics | 1978 |
| Ab Panzetta Oy | Hospitality | 1995 |
| Ab PratSam Oy | Wholesale & retail | 2005 |
| Ab Pucco Oy | Manufacturing | 2018 |
| Ab RoBeck Cargo Care Oy | Transport & logistics | 2017 |
| Ab Salvares Oy | Health & social care | 2016 |
| Ab Sera Partners Oy | Real estate | 2021 |
| Ab Sidwill Oy | Manufacturing | 1998 |
| Ab Skogsfastigheter AFM | Real estate | 2008 |
| Ab Sparal Oy | Construction | 2008 |
| Ab Sports Gym Wasa Oy | Arts & recreation | 1987 |
| Ab Star Trikå Oy | Manufacturing | 2026 |
| Ab Storgårds Rör-Putki Oy | Construction | 1996 |
| Ab Strands Oy | Professional & scientific | 1983 |
| Ab Suncas Ltd | Financial services | 1989 |
| Ab SvedTech Oy | Professional & scientific | 2014 |
| Ab Svenska Småbruk i Österbotten | Real estate | 1918 |
| Ab Team Norrgård Oy | Hospitality | 2017 |
| Ab Tecnotools Vasa Oy | Professional & scientific | 1996 |
| Ab Transport Helge Kull Oy | Transport & logistics | 1980 |
| Ab VVS-Planering K Lindgrén | Professional & scientific | 1998 |
| Ab Vasa Byggnadsreparation - Vaasan Rakennuskorjaus Oy | Construction | 1976 |
| Ab Vasa Vörågatan 1-3 | Real estate | 1989 |
| Ab Vattenplanering F. Brännback Oy | Construction | 1993 |
| Ab Waktos Oy | Financial services | 1986 |
| Ab Wanha Wasa Catering Oy | Hospitality | 2002 |
| Ab Wasa Gym Trading Oy | Arts & recreation | 1987 |
| Ab Wolf-Tech Oy | Professional & scientific | 2020 |
| Ab Yrkeshögskolan vid Åbo Akademi | Education | 2006 |
| Abjoy Oy | Hospitality | 2000 |
| Achaemenid Oy | Information & communication | 2017 |
| Acosta Group Oy | Construction | 2021 |
| Acosta Jyväskylä Oy | Construction | 2021 |
| Active Rehab Kb | Health & social care | 1987 |
| Acume Hedge Oy | Financial services | 1997 |
| Addent Import Oy | Wholesale & retail | 2023 |
| Adente Tandläkarna Ab | Health & social care | 2011 |
| Adeprimo AB filial i Finland | Professional & scientific | 2009 |
| Adiabatix Oy | Construction | 2000 |
| Adimo Oy Ab | Information & communication | 2015 |
| Advokatbyrå Boucht & Nikula Asianajotoimisto | Professional & scientific | 1975 |
| Advokatbyrå Kim Åstrand Ab | Professional & scientific | 2014 |
| Advokatbyrå Näsman & Båsk Ab | Professional & scientific | 2015 |
| Aethos Technologies Ab Oy | Information & communication | 2024 |
| Afiifi Gourmet Oy | Hospitality | 2023 |
| Agapornia Oy | Financial services | 1990 |
| Agentor Oy | Administrative & support | 2004 |
| Ahavatuuli Oy | Real estate | 1990 |
| Airaksinen Capital Oy | Real estate | 1990 |
| Airaksinen Equity Holding Oy | Financial services | 2019 |
| Airistolat Oy | Other services | 2024 |
| Airtec Anderssen Oy Ab | Construction | 2022 |
| Aito-Kotihoito Oy | Health & social care | 2009 |
| Ajan Hammas Oy | Health & social care | 1973 |
| Ajan Laboratorio Oy | Manufacturing | 1987 |
| Aki Aapio Oy Ab | Financial services | 2021 |
| Akku-Alanko Oy | Wholesale & retail | 1961 |
| Akku-Salminen kommandiittiyhtiö | Wholesale & retail | 1976 |
| Alevi Invest Ab | Financial services | 2013 |
| Alexin Hovi Oy | Transport & logistics | 2014 |
| Alfa Fortune Oy | Real estate | 2017 |
| Alho Services Oy | Administrative & support | 2025 |
| Alice Keski-Valkama Oy | Health & social care | 2022 |
| Aligned Coaching Oy | Other services | 2025 |
| All in All IT-Solutions Oy Ab | Information & communication | 2001 |
| Allein Oy | Information & communication | 2018 |
| Allokaatio Oy | Real estate | 2023 |
| Almnorth Oy | Information & communication | 2019 |
| Alpha Billion Oy | Administrative & support | 2016 |
| Alpine Work and Shop Avoin yhtiö | Wholesale & retail | 2012 |
| Alpinedoc Oy Ab | Health & social care | 2017 |
| Alskatin Kenttä Oy | Manufacturing | 2016 |
| Alueen Hammas-Garaisi Oy | Health & social care | 1994 |
| Alulaakso Oy | Manufacturing | 1985 |
| Aluri Oy | Professional & scientific | 2006 |
| Amazing Juoma Ab Oy | Wholesale & retail | 2023 |
| Amelia Creation Oy | Professional & scientific | 2026 |
| Ameoli Oy | Wholesale & retail | 2014 |
| Ammantis Oy Ab | Professional & scientific | 2019 |
| Ampner Oy | Professional & scientific | 2012 |