| Holini Oy | Hospitality | 2014 |
| Hommanäs Gård Oy Ab | Manufacturing | 2011 |
| Honkala Bistro Oy | Hospitality | 2022 |
| HopeShop Oy | Hospitality | 2022 |
| Hopea & Co avoin yhtiö | Wholesale & retail | 1959 |
| Hopeakello Oy | Wholesale & retail | 2000 |
| Hopealinna Oy | Professional & scientific | 2014 |
| Hopeaportti Oy | Financial services | 1990 |
| Horina OY | Arts & recreation | 2019 |
| Hornhattulan Kiinteistövalvomo Oy | Real estate | 2019 |
| Horse Cart Factory Oy | Manufacturing | 2021 |
| Hosiokoski Investment Oy | Financial services | 2023 |
| Hostaava Oy | Real estate | 2026 |
| Hotel Haikko Oy | Hospitality | 2016 |
| Hotelli Pariisin Ville Oy | Administrative & support | 2006 |
| House of The Good Feelings Oy | Arts & recreation | 2007 |
| Hovén & Co Oy | Professional & scientific | 2019 |
| Hua Wu Oy | Hospitality | 2006 |
| Hugo Music Oy | Arts & recreation | 2023 |
| Hukka AI Oy | Information & communication | 2019 |
| Humaanikone Oy | Administrative & support | 2013 |
| Huoltamo Holmi Ky | Wholesale & retail | 1966 |
| Huoltoasema I & K Vainio Ky | Wholesale & retail | 1989 |
| Huoltoliike AHO-Service OY | Wholesale & retail | 1993 |
| Huoltopalvelu J. Holmberg Oy | Other services | 1987 |
| Huuri Consulting Oy | Professional & scientific | 2023 |
| Hygieia Oy | Administrative & support | 2019 |
| Hyvinvoinnin Pelikenttä Oy | Other services | 2018 |
| Hyvinvointihuone 2.0 Oy | Arts & recreation | 2026 |
| Hyvinvointikeskus Louisé Ky | Health & social care | 1986 |
| Hämeen Lämpöeriste Oy | Construction | 2020 |
| Hämmästy! Oy | Arts & recreation | 2019 |
| Hämäläinen Partners Oy | Administrative & support | 2026 |
| Håkan Eriksson Kb | Transport & logistics | 1987 |
| Höglund & Höglund Oy Ab | Construction | 1999 |
| Höyrytys Sandström Oy | Construction | 2006 |
| ICL Legal & Policy Consulting Oy Ltd | Professional & scientific | 2025 |
| IDEA-Rakennus Oy | Construction | 2008 |
| IK-20 Oy | Construction | 2019 |
| ILO Hockey Oy | Arts & recreation | 2022 |
| ILPasonic Oy | Construction | 2023 |
| ILPon Sähkö Oy | Construction | 2016 |
| IME holding Oy | Financial services | 2024 |
| IRGF Oy | Financial services | 2025 |
| ITR Sprinklerihuolto Oy | Construction | 2011 |
| IUIP Oy | Construction | 2023 |
| IV Spesialistit Oy Ab | Construction | 2010 |
| Icy North Games Oy | Information & communication | 2018 |
| IdeaLaukka Oy | Real estate | 2020 |
| Ihalainen Holding Oy | Financial services | 2023 |
| Ihonhoito & Hyvinvointi OLO Oy | Other services | 2021 |
| Iisi Laatoitus Ky | Construction | 2008 |
| Ilkan Kone Ky | Wholesale & retail | 1984 |
| Illuusio J. Henriksson Ky | Information & communication | 1996 |
| Ilmalinkki Oy | Construction | 1995 |
| Ilmanvaihto J.Pulkkinen Oy | Construction | 2022 |
| Ilmavaltiaat Oy | Professional & scientific | 2018 |
| Ilmawat pidot Oy | Arts & recreation | 2024 |
| IlonKauttaValmennus Oy | Health & social care | 2019 |
| Image Design Oy | Administrative & support | 1991 |
| Immel Lake Resort Oy | Hospitality | 2026 |
| In-Shop Oy | Administrative & support | 1980 |
| Incredible Design Partners Oy | Professional & scientific | 2021 |
| Indigo Media Ab | Professional & scientific | 2020 |
| Induro Oy | Wholesale & retail | 2025 |
| Infio Oy | Wholesale & retail | 2019 |
| Infra Nation Oy | Construction | 2023 |
| Infra Tronic Oy | Construction | 2025 |
| Ink Panther Oy | Wholesale & retail | 2009 |
| Innergame Finland Oy | Arts & recreation | 2010 |
| InnoLearny Oy | Professional & scientific | 2024 |
| Innocate Oy | Professional & scientific | 2008 |
| Innofarma Oy | Administrative & support | 2023 |
| Innoline Oy | Professional & scientific | 1990 |
| Innosolutions Oy | Administrative & support | 2012 |
| Insinööritoimisto Jari Nieminen Ky | Professional & scientific | 2001 |
| Insinööritoimisto K Piispa Oy | Professional & scientific | 1991 |
| Insinööritoimisto KIEMA Oy | Real estate | 2017 |
| Insinööritoimisto Lauri Palmén Oy | Professional & scientific | 2012 |
| Insinööritoimisto Nordvik Oy | Professional & scientific | 2026 |
| Insinööritoimisto Risku Prosessihallinta Ky | Professional & scientific | 1989 |
| Insinööritoimisto Timo Alapere Oy | Professional & scientific | 1989 |
| Inspiration 4 You Oy | Wholesale & retail | 2008 |
| Insplan Oy | Professional & scientific | 2015 |
| Insula Finland Oy | Professional & scientific | 2019 |
| Integria Oy | Professional & scientific | 2026 |
| Intentium Oy | Professional & scientific | 2002 |
| Invenor Oy | Professional & scientific | 1982 |
| Iotoi Oy | Professional & scientific | 2018 |
| Ippe Trade Oy | Wholesale & retail | 2026 |
| Irbis Scandinavia Oy | Professional & scientific | 2016 |
| Isolla Music Oy | Arts & recreation | 2016 |
| Isännöinti Taimi Oy | Real estate | 2014 |
| Itä Uudenmaan Pihakaivin Oy | Construction | 2023 |
| Itä-Uudenmaan Kiinteistö ja Tontti Oy | Construction | 2003 |
| Itä-Uudenmaan LVI Asennus Oy | Construction | 2015 |
| Itä-Uudenmaan Rakennuspalvelu Oy | Wholesale & retail | 1987 |
| Itäkolmio Oy | Arts & recreation | 1989 |
| Itäväylä Viestintä Oy | Information & communication | 2013 |
| Itäväylän Kosmetiikka Oy | Wholesale & retail | 2001 |