| HM-Automaatio Oy | Professional & scientific | 2000 |
| HMH-Sähköt Oy | Construction | 1991 |
| HN experience oy | Manufacturing | 2022 |
| HOVI Consulting Oy | Professional & scientific | 2020 |
| HPMM Services Oy | Professional & scientific | 2018 |
| HQ Code Shop Oy | Information & communication | 2010 |
| HRP-Rakennus Oy | Construction | 2004 |
| HRT Rakennus Oy | Construction | 2002 |
| HS-Engineering Oy | Professional & scientific | 1998 |
| HS-Salonki Ky | Other services | 1981 |
| HYDLAPP Oy | Wholesale & retail | 2011 |
| HaVe Palvelut Oy | Wholesale & retail | 2026 |
| HaaRentals Oy | Administrative & support | 2025 |
| HaaService Oy | Manufacturing | 2026 |
| Haakon Chartering Oy | Wholesale & retail | 2013 |
| Haapasalo Metsä Oy | Agriculture & fishing | 2025 |
| Haikea Oy | Information & communication | 2021 |
| Haiku Creative Oy | Professional & scientific | 2022 |
| Haji Qasim Oy | Hospitality | 2024 |
| Hakali Pro Oy | Wholesale & retail | 2025 |
| Hakalin Kiinteistönjalostus Oy | Real estate | 1997 |
| Hakamie Yhtiöt Oy | Wholesale & retail | 2019 |
| Hakepojat Oy | Manufacturing | 1988 |
| Hammaslaboratorio Saimaan Hammas Oy | Manufacturing | 2015 |
| Hammaslääkäri Merja Kokkola Oy | Health & social care | 1995 |
| Hammasnorppa Oy | Health & social care | 2019 |
| Hammasvuokko Oy | Health & social care | 1999 |
| Hanhijärven valokuituosuuskunta | Information & communication | 2016 |
| Hanhijärven vesiosuuskunta | Water & waste | 2000 |
| Hankitek Oy | Wholesale & retail | 2000 |
| Hanne Laitinen Oy | Wholesale & retail | 1996 |
| Hansavest Työvoima Oy | Administrative & support | 2016 |
| HappyZach Oy | Hospitality | 2024 |
| HarVa Hammas Oy | Health & social care | 2021 |
| Harley Parts Oy | Wholesale & retail | 2021 |
| Harpmotor Oy | Wholesale & retail | 1999 |
| Harvio Oy | Real estate | 1964 |
| Hasnaat Oy | Hospitality | 2024 |
| Hasura Ky | Construction | 1988 |
| Hautaustoimisto Nyberg Oy | Other services | 1979 |
| Hautaustoimisto ja Kukkakauppa Tolvanen Oy | Other services | 1980 |
| HaveFun Oy | Arts & recreation | 2021 |
| Headnought Oy | Information & communication | 2013 |
| Health Doctor Oy | Health & social care | 2024 |
| Heikki Sintonen Oy | Professional & scientific | 2017 |
| Heikki ja Elena Kosonen Oy | Hospitality | 2006 |
| Heikomet Oy | Manufacturing | 2005 |
| Heimo Hiekkala Ky | Wholesale & retail | 1983 |
| Heini Holding Oy | Real estate | 2021 |
| Heinikodit Oy | Health & social care | 1997 |
| Heiskamo O.Y. Autokorjaamo | Other services | 1944 |
| Heivain kommandiittiyhtiö | Manufacturing | 1988 |
| Heka Urakointi Oy | Construction | 2020 |
| Hekatek Oy | Professional & scientific | 2018 |
| Hela Holding Oy | Financial services | 2023 |
| Helen Kauneuskeskus Juvonen Ky | Other services | 1989 |
| Helmien Oy | Hospitality | 2017 |
| Helsingin LV-Asennus Oy | Construction | 2023 |
| Helsingin Pihaleikkiväline Oy | Construction | 1989 |
| Hemi Rakennus Oy | Construction | 2015 |
| Herkkukassler Oy | Wholesale & retail | 2025 |
| HetkiLux Oy | Arts & recreation | 2025 |
| Hieronta- ja hyvinvointipalvelut Hoitavat kädet Osk | Health & social care | 2026 |
| Hildén Company Oy | Wholesale & retail | 2023 |
| Hiltusen Markkinointi HilMa Oy | Professional & scientific | 2019 |
| Himakivi Oy | Real estate | 2007 |
| Hirven Saha avoin yhtiö | Manufacturing | 2006 |
| HiskiShow Oy | Information & communication | 2018 |
| HiusHuone 27 Oy | Other services | 2020 |
| Hiuskeskus Marjo Kouhia Ky | Other services | 1983 |
| Hjelt & Co Oy | Financial services | 2024 |
| Hobby & Bitti Oy | Wholesale & retail | 2014 |
| HoiValo Oy | Health & social care | 2025 |
| Hoitoa Kotiin Oy Heidi Pellinen | Health & social care | 2008 |
| Hoivapalvelut M&M Oy | Health & social care | 2012 |
| Hoivita Oy | Information & communication | 2022 |
| Holiday Cottages Finland Oy | Administrative & support | 2007 |
| Holmine Ky | Manufacturing | 1989 |
| Home Fixer's Oy | Construction | 2011 |
| Homéne Oy | Health & social care | 2020 |
| Honghui Oy | Hospitality | 2025 |
| Horizon Ecommerce Oy | Wholesale & retail | 2020 |
| Horsepower Ahola Oy | Education | 2018 |
| Horseteq Oy | Information & communication | 2015 |
| Hotelli Olkkolan Hovi Oy | Hospitality | 2016 |
| Huhti Haarikka Ky | Hospitality | 1992 |
| Hulkkosen Kodit Oy | Real estate | 2024 |
| Hultin Partners Oy | Professional & scientific | 1994 |
| Humble Rental Oy | Other services | 1999 |
| Huolto-Särkkä Oy | Manufacturing | 1992 |
| Huoltopiste Walle Ky | Other services | 1990 |
| Huopainen Oy | Financial services | 2025 |
| Huttunen korjausrakentaminen Oy | Construction | 2024 |
| Huveta Oy | Financial services | 2021 |
| Hymysi Oy | Health & social care | 2021 |
| HytPal Oy | Construction | 2011 |
| Hyvinvoinnin ABC Oy | Other services | 1989 |
| Hyvinvointi Saraste Oy | Health & social care | 2018 |
| Hyväri Works Oy | Manufacturing | 2021 |
| Häva Group Oy | Arts & recreation | 2024 |