| HammasVäli Oy | Health & social care | 2025 |
| Hammaslaboratorio J. Leppänen Ky | Manufacturing | 2014 |
| Hammaslaboratorio Lakeuden Hammas Ky | Manufacturing | 1981 |
| Hammaslaboratorio P. Hemminki ky | Manufacturing | 1966 |
| Hammaslaboratorio, erikoishammasteknikko Jukka Ropponen Oy | Manufacturing | 1994 |
| Hammaslääkäri Nina Pahkala Oy | Health & social care | 2026 |
| Hammaslääkäri T. Naamanka Oy | Health & social care | 2016 |
| Hammaslääkärit Vesala Oy | Health & social care | 2009 |
| Hammaspalvelu Laitinen Oy | Health & social care | 2007 |
| Hammasteknikko Timo Haapamäki Oy | Manufacturing | 2020 |
| Hammasterveys Laitinen Oy | Health & social care | 2022 |
| Hammeri Oy | Construction | 2019 |
| Handent Oy | Health & social care | 2022 |
| Hangman Brothers Oy | Financial services | 2025 |
| HannaHau Oy | Professional & scientific | 2021 |
| Hannu Malmivaara Ky | Wholesale & retail | 2018 |
| Hannu-Group Oy | Agriculture & fishing | 1994 |
| Hansa Kehitys Oy | Education | 1982 |
| Hantulan Liikenne Oy | Transport & logistics | 2006 |
| Happy Parturi Oy | Other services | 2023 |
| Harjutex Ky | Manufacturing | 1985 |
| Harri Invest Oy | Financial services | 2022 |
| Haryana Group Oy | Transport & logistics | 2023 |
| Haukilehto Invest Oy | Financial services | 2025 |
| Haukkis Grilli Oy | Hospitality | 2020 |
| Haustramnia Casa Oy | Other services | 1995 |
| Haustramnia Services Oy | Administrative & support | 2010 |
| Hautala Group Oy | Financial services | 2021 |
| Hautaluoma-Yhtiö Oy | Transport & logistics | 2020 |
| Hautaluoman Grilli Oy | Hospitality | 2024 |
| Hautamäki Training Oy | Health & social care | 2008 |
| Hautaustoimisto Hymni Oy | Other services | 2022 |
| Havi Sales Oy | Financial services | 2023 |
| Havu Health Ab | Manufacturing | 2025 |
| Hawkline Oy | Real estate | 2001 |
| Heatmac Oy | Manufacturing | 2019 |
| Hecumaa oy | Manufacturing | 2021 |
| Hefilia Oy | Financial services | 2022 |
| Heidi Koskinen Holding Oy | Professional & scientific | 2023 |
| HeimHostel Oy | Hospitality | 2024 |
| Helahalli Oy | Real estate | 2020 |
| Helatukku Finland Oy | Wholesale & retail | 1982 |
| Helpy Oy | Administrative & support | 2022 |
| Helsingin Rejo-Haro Ky | Wholesale & retail | 1978 |
| Hemimotors Oy | Wholesale & retail | 1999 |
| Henkka Plan Oy | Real estate | 2022 |
| Henna Poti Oy | Administrative & support | 2023 |
| Herkkukartano Oy | Wholesale & retail | 2018 |
| Herkoolin Kartanot Oy | Real estate | 2004 |
| Hevihill Ky | Real estate | 1990 |
| Hietamäen Kuljetus Oy | Transport & logistics | 1995 |
| Hietaniemi Group Oy | Professional & scientific | 2024 |
| Hietaranta Capital Oy | Real estate | 2022 |
| Highspeed Consulting Oy | Arts & recreation | 2007 |
| Hikihelmi Oy | Professional & scientific | 1992 |
| HilPeä Entertainment Oy | Arts & recreation | 2015 |
| Hill Live Oy | Professional & scientific | 2021 |
| Hirven Konepaja Oy | Manufacturing | 2024 |
| Hitsauskonemyynti Poola & Poola | Wholesale & retail | 1985 |
| Hiusstudio Cosmo Ky | Other services | 2015 |
| Hiuta Oy | Education | 2012 |
| HoReCa Interior Oy | Wholesale & retail | 2020 |
| Hoitola Yrjänäinen Oy | Real estate | 2001 |
| Hoitopuu Oy | Health & social care | 2011 |
| Holotna Oy | Information & communication | 2017 |
| HolviAuto Oy | Real estate | 2022 |
| Horsman Holding Oy | Professional & scientific | 2024 |
| Hotelli Utsjoki Oy | Hospitality | 2019 |
| HtF Industry Oy | Manufacturing | 2024 |
| Hucca Clothing Oy | Wholesale & retail | 2022 |
| Huhtala Logistics Oy | Transport & logistics | 2017 |
| Huipulla Oy | Hospitality | 2021 |
| Huoltamo Kari Rinta Oy | Wholesale & retail | 1993 |
| Huoltopiste Ahvenainen Oy | Other services | 2023 |
| Huonekaluhalli J. Toppari Ky | Wholesale & retail | 2014 |
| Huttaroo Oy | Wholesale & retail | 2016 |
| Huumarsalo Invest Oy | Financial services | 2018 |
| Huushollijelppari Oy | Administrative & support | 2013 |
| Huvi Luola Oy | Administrative & support | 2025 |
| Huvipirtti Oy | Professional & scientific | 2016 |
| Hypersolutions Oy | Professional & scientific | 2017 |
| Hypnoise Oy | Arts & recreation | 2021 |
| Hyvähyvä oy | Professional & scientific | 2021 |
| Hyvällä Oy | Education | 2023 |
| Hyötyliike Oy | Education | 2018 |
| Härmän Tilintarkastus ja Laskenta Oy | Professional & scientific | 1987 |
| Hölsö Group oy | Manufacturing | 2024 |
| I-print Oy | Manufacturing | 1983 |
| ILP Pekka Oy | Construction | 2023 |
| IMP Consulting Ky | Wholesale & retail | 2023 |
| IPC Oy | Health & social care | 2019 |
| ISK-Invest Ky | | 1987 |
| ISLE Art Industries Oy | Information & communication | 2017 |
| Isokungas Invest OY | Real estate | 2010 |
| Ispotec OY | Professional & scientific | 2009 |
| Ibico Teräsrakennus Oy | Construction | 2018 |
| Ibo.07 Oy | Hospitality | 2018 |
| Idama Oy | Wholesale & retail | 2020 |
| Ideamani Oy | Other services | 2019 |
| Ihan-A Oy | Hospitality | 2022 |