| Tsuppari Lähettipalvelu Oy - Tsuppari Budservice Ab | Transport & logistics | 1984 |
| Tucone Consulting Oy | Administrative & support | 2018 |
| Tuholaisetvex Oy | Administrative & support | 1998 |
| Tukkuliike Wiklund Ky | Wholesale & retail | 1983 |
| Tulikankaan tuulivoimahanke Oy | Energy | 2024 |
| Tuohex Capital Oy | Financial services | 2020 |
| Tuohex Kiinteistörahasto I Ky | Financial services | 2021 |
| Tuplataito Oy | Manufacturing | 1993 |
| Turkistarha A Lintunen & P Lintunen | Agriculture & fishing | 1986 |
| Tuula Perälä Ky | Wholesale & retail | 1995 |
| Tuulikarhu Oy | Energy | 2022 |
| Tuulipuisto Pontema Oy | Energy | 2020 |
| Two Things Oy | Wholesale & retail | 2007 |
| TwoKays Ab | Financial services | 2020 |
| Tyynismaa Capital Oy | Professional & scientific | 2016 |
| Törmä Training & Creative Oy | Education | 2024 |
| UIUI Software Oy | Information & communication | 2024 |
| UPC Konsultointi Oy | Manufacturing | 1988 |
| UPC Media Oy | Information & communication | 1995 |
| US tilipalvelu Ky | Professional & scientific | 2002 |
| Ukko Finland Oy | Wholesale & retail | 2017 |
| Ukkokari Production Oy | Hospitality | 2017 |
| Uncle Woo Asian Food Oy | Wholesale & retail | 2012 |
| Underland Oy | Professional & scientific | 2024 |
| Understandify Ab Oy | Information & communication | 2024 |
| Unelmatekniikka Oy | Professional & scientific | 2015 |
| Unex Oy | Wholesale & retail | 2015 |
| Unger & Martins Kb | Arts & recreation | 2010 |
| United Clothing Brands Finland Oy | Wholesale & retail | 2021 |
| Unlimited Smartdeals Solutions Oy Ab | Wholesale & retail | 2012 |
| Ura Health Oy | Health & social care | 2019 |
| Urakointi Veikkola Oy | Construction | 1998 |
| Urheilu ja Vapaa-aika, Mauri Johannes Viking Öljymäki Ky | Wholesale & retail | 1982 |
| Urodoc Oy | Health & social care | 2007 |
| Ursa Demolition Oy | Construction | 2024 |
| Usvaputki Oy | Arts & recreation | 1997 |
| Uudenmaan Tasoite- ja Maalauspalvelu OY | Construction | 2021 |
| Uurastuuri Oy | Real estate | 2010 |
| Uwira Oy | Manufacturing | 1993 |
| V.E.A. Invest Oy | Real estate | 1975 |
| V.K.Ketonen Oy | Manufacturing | 1982 |
| VAC Invest Oy | Wholesale & retail | 2021 |
| VAMC Oy | Professional & scientific | 2026 |
| VAMM Steel Oy | Manufacturing | 2014 |
| VASARÖR Ab | Construction | 2009 |
| VEO Kiinteistöt Oy | Real estate | 1980 |
| VEO Oy | Manufacturing | 2000 |
| VIC Invest Oy | Real estate | 1971 |
| Visnec Holding OY AB | Financial services | 2014 |
| VIZA Media Oy | Information & communication | 2026 |
| VJTH Investments Oy | Real estate | 2021 |
| VM-Group Oy | Manufacturing | 1989 |
| VMJ Sillanpää Oy | Professional & scientific | 2021 |
| VOYB Oy | Agriculture & fishing | 2018 |
| VP Facilities Oy Ab | Real estate | 2018 |
| VRSports Ab | Education | 2024 |
| Vaasa Business Travel Oy Ab | Administrative & support | 2004 |
| Vaasa Clippoteque Ky | Other services | 1998 |
| Vaasa Day Spa Oy | Other services | 2007 |
| Vaasa Facilita Oy Ab | Real estate | 1982 |
| Vaasa Hikers Ky | Administrative & support | 2018 |
| Vaasa Karting Oy | Arts & recreation | 2019 |
| Vaasa Parks Oy Ab | Real estate | 2018 |
| Vaasa Phone Service Ky | Other services | 2014 |
| Vaasa Ravintolat Oy | Hospitality | 2007 |
| Vaasa Smiles Oy/Ab | Health & social care | 2022 |
| VaasaPlot Siivouspalvelut Oy | Administrative & support | 2025 |
| Vaasaintoclean Oy | Administrative & support | 2019 |
| Vaasan Akut Oy Ab | Wholesale & retail | 2012 |
| Vaasan Arel Trading Ky | Wholesale & retail | 2000 |
| Vaasan Arvonletka Oy | Real estate | 1978 |
| Vaasan Asunto-osuuskunta Omakoti | Real estate | 1912 |
| Vaasan Autocenter Oy | Wholesale & retail | 2017 |
| Vaasan Autovuokraamo Ky | | 1982 |
| Vaasan Beauty Center Ky | Other services | 1991 |
| Vaasan Best-kenkä Hannu Vihanto Ky | Wholesale & retail | 1992 |
| Vaasan Burger Oy | Hospitality | 1995 |
| Vaasan EKL-palvelut Oy | Transport & logistics | 2019 |
| Vaasan Eines Ky Airi Lintunen | Manufacturing | 1987 |
| Vaasan Einesmestarit Wennberg Ky | Hospitality | 1983 |
| Vaasan Endolab Oy | Health & social care | 1988 |
| Vaasan Erikoisauto avoin yhtiö | Transport & logistics | 1987 |
| Vaasan Food Service Oy | Hospitality | 2021 |
| Vaasan Futuflow Ravintolat Oy | Hospitality | 2008 |
| Vaasan Grilli-Varuste Ky | Wholesale & retail | 1986 |
| Vaasan Habita Oy | Real estate | 2005 |
| Vaasan Hammaslääkärit Oy Oy Vasa Tandläkarna Ab | Health & social care | 1976 |
| Vaasan Huolto ja Kierrätys Oy - Vasa Service och ÅtervinningAb | Administrative & support | 1998 |
| Vaasan Huoneistoremontti Oy | Construction | 2010 |
| Vaasan Ilmalämpökeskus Oy | Construction | 2024 |
| Vaasan Ilmastointi Oy | Construction | 1974 |
| Vaasan Juniorihallit Oy | Arts & recreation | 1998 |
| Vaasan Jäähallin Ravintolat Oy | Hospitality | 2001 |
| Vaasan Kiinteistöhuolto - Vasa Fastighetsservice Ab Oy | Administrative & support | 2026 |
| Vaasan Kiinteistökorjaus Oy | Construction | 2022 |
| Vaasan Kiinteistöpalvelu Oy | Administrative & support | 2024 |
| Vaasan Kiitorata Oy | Real estate | 2011 |
| Vaasan Kivat Kodit Oy | Professional & scientific | 2018 |
| Vaasan Kodinkonehuolto Oy | Other services | 1999 |
| Vaasan Korttelihuolto Oy | Administrative & support | 2015 |