| Helvia Oy | Professional & scientific | 2009 |
| Hemagon Oy | Education | 2013 |
| Hemminkäinen Oy | Construction | 2024 |
| Hemmola Oy | Wholesale & retail | 2016 |
| Hemsten Group Oy | Administrative & support | 2019 |
| Henkilöstövalmennus ja -liikunta Jyväskylän efector Oy | Education | 1990 |
| Hennalan Kasarmi 23 Oy | Real estate | 2020 |
| Herkkukeisari Avoin Yhtiö | Wholesale & retail | 2011 |
| Hermaala Oy | Professional & scientific | 1973 |
| Herrasen Putki Oy | Construction | 1991 |
| HerttaRuutu Oy | Financial services | 2011 |
| Herttalassa Oy | Other services | 2017 |
| Hesam Iranloo Oy | Hospitality | 2025 |
| Heta kodit Oy | Construction | 2021 |
| Hidpex Group Oy | Construction | 2026 |
| Hidpex Oy | Construction | 2018 |
| Hienoopeliä Oy | Professional & scientific | 2019 |
| Hieronta ja kuppaus Sirkku Lahtinen Ky | Other services | 1999 |
| High Voltage Group Oy | Wholesale & retail | 2004 |
| Highsight Media Group Oy | Information & communication | 2016 |
| Hilirimpsis Oy | Real estate | 2019 |
| Hilja Lehtivuori Oy | Arts & recreation | 2020 |
| Hilja-Line Oy | Transport & logistics | 2022 |
| Hillevi Mekuria Ky | Wholesale & retail | 2008 |
| Himos Viikkolomat Ky | Construction | 2012 |
| Hinauspalvelu Hinaus-Team Oy | Transport & logistics | 2021 |
| Hiomo Kantanen Oy | Other services | 2005 |
| Hirvi & Crew Osk | Professional & scientific | 2026 |
| Hitcon Oy | Manufacturing | 1981 |
| Hitto Impact Solutions Oy | Information & communication | 2021 |
| Hius Miia's Oy | Other services | 2020 |
| Hius- ja Kauneusstudio Chilling Oy | Other services | 2010 |
| Hiussali Silvennoinen Ky | Other services | 2004 |
| Hiusstudio Live Oy | Other services | 2019 |
| Hoivakeittiöt Oy | Hospitality | 2015 |
| Hoivapörssi Oy | Health & social care | 1997 |
| Hoka-Majat Oy | Real estate | 1990 |
| Hokas Oy | Financial services | 2022 |
| Hokkama Varainhoito Oy | Professional & scientific | 2025 |
| Holding TR Oy | Financial services | 2021 |
| Home By Livia Oy | Hospitality | 2019 |
| Home Island Holding Oy | Financial services | 2025 |
| HomeHarmony Innovations Oy | Professional & scientific | 2025 |
| Hong Kong City Senko Trading avoin yhtiö | Hospitality | 2008 |
| Honkoworks Oy | Administrative & support | 2021 |
| Hopealintu Ky | Professional & scientific | 1986 |
| Hormel Oy | Wholesale & retail | 1988 |
| Hotelli Milton Oy | Hospitality | 1992 |
| Hovi Production Oy | Information & communication | 2024 |
| Hox Bakery Oy | Manufacturing | 2019 |
| Hox City Oy | Hospitality | 2019 |
| Huhtakangas Oy | Transport & logistics | 2023 |
| Humalajoen Marja Oy | Financial services | 1993 |
| Humap Oy | Education | 2000 |
| Humm Group Oy | Information & communication | 2012 |
| Humm Services Oy | Professional & scientific | 2017 |
| Hunni & Lunni Holdings Oy | Financial services | 2012 |
| Huojuva Latva Oy | Financial services | 2020 |
| Huoltamo Hytönen Oy | Other services | 2022 |
| Huolto Riihi Oy | Other services | 2017 |
| Huolto ja Kuljetus T. Linden Oy | Transport & logistics | 2009 |
| Huolto-Hui Oy | Other services | 2026 |
| Huolto-Kalle Oy | Other services | 2000 |
| Huoltoasema Keinusaari Ky | | 1979 |
| Huoltokukko Oy | Other services | 1967 |
| Huoltopalvelu A.Vettainen Oy | Other services | 2026 |
| Huoltopilotti Oy | Other services | 2016 |
| Huoneistoremontit A. Matilainen Oy | Construction | 2008 |
| Huse Oy | Agriculture & fishing | 2026 |
| Hutlake Data Solutions Oy | Information & communication | 2021 |
| Huttunen Capital Oy | Financial services | 2024 |
| Huvimestari Oy | Arts & recreation | 2021 |
| Hy-ber Oy | Information & communication | 2022 |
| Hyd-Jar Oy | Manufacturing | 2019 |
| HydFin Oy | Manufacturing | 2016 |
| Hydsupply Oy | Wholesale & retail | 1986 |
| Hytco Oy | Wholesale & retail | 2004 |
| Hytecon Oy | Real estate | 2011 |
| Hytinä Oy | Arts & recreation | 2022 |
| Hyvinvoinnin First Aid Oy | Health & social care | 2022 |
| Hyvinvoinnin kompassi osk | Arts & recreation | 2026 |
| Hyvinvointi ja Kuntoutus Amida Oy | Health & social care | 2017 |
| Hyvinvointia Aalloista Oy | Health & social care | 2020 |
| Hyvinvointipalvelut Minna Taipale Oy | Health & social care | 2021 |
| Hyvio oy | Information & communication | 2026 |
| Hyötybiili Oy | Wholesale & retail | 2024 |
| Hämeen Autovaruste Oy | Wholesale & retail | 1995 |
| I&J Hartikainen Oy | Wholesale & retail | 1993 |
| I&T Company Ky | Wholesale & retail | 2019 |
| IA Holding 2 Oy | Financial services | 2026 |
| IA Holding Oy | Financial services | 2021 |
| IA Sijoitus Oy | Financial services | 1994 |
| IBL Solution Oy | Information & communication | 2011 |
| IC Finland Oy | Manufacturing | 2000 |
| ICHA Hair & Beauty Oy | Wholesale & retail | 2024 |
| IDiSS Industrial Oy | Information & communication | 2024 |
| IH Sales Oy | Wholesale & retail | 2026 |
| IINES-tuotanto Oy | Arts & recreation | 2024 |
| IIP Invest in People Oy | Professional & scientific | 2005 |
| IKS-Rakennus Oy | Construction | 2016 |