| Hattulan Halko Oy | Transport & logistics | 2009 |
| Hattulan Kelloseppä ky, Heikki Horma | Wholesale & retail | 1985 |
| Hauhon Hiekka Oy | Administrative & support | 2005 |
| Hauhon Kiinteistöala Oy | Administrative & support | 1993 |
| Haukka koulutus ja kehitys Oy | Professional & scientific | 2024 |
| Hautakiviveistämö Matti Kaila Oy | Manufacturing | 1989 |
| Hautauspalvelu Kaila Oy | Other services | 1990 |
| Havulaavu Oy | Arts & recreation | 2020 |
| He-Ti Huolto Oy | Administrative & support | 2022 |
| HeVi Steel Oy | Manufacturing | 2025 |
| Health online learning Oy | Education | 2023 |
| Heatcon Oy | Professional & scientific | 2020 |
| Heidi Jääskeläinen Oy | Professional & scientific | 2020 |
| Heidi Kyrö Ky | Professional & scientific | 2004 |
| Heimo Rakentaja Oy | Professional & scientific | 2011 |
| Heivest Invest Oy | Financial services | 2023 |
| Helangår-kiinteistöt Oy | Real estate | 2025 |
| Helenit Oy | Professional & scientific | 2023 |
| HellaHuone Design Oy | Wholesale & retail | 2023 |
| Helli & Sisters Oy | Wholesale & retail | 2022 |
| Helmes FlowWorks Oy | Information & communication | 2026 |
| Helmi HiusmESta avoin yhtiö | Other services | 2008 |
| HelmiLife Oy | Health & social care | 2024 |
| Helmia Oy | Construction | 2026 |
| Helmiina Kotipalvelut Oy | Health & social care | 2018 |
| Helminen & Valli Oy | Wholesale & retail | 1996 |
| Helmivouti Oy | Health & social care | 2020 |
| Helmiä Oy | Health & social care | 2018 |
| Helén Invest Oy | Health & social care | 2007 |
| Hennot Siivet Oy | Health & social care | 2019 |
| Henri Purhonen Oy | Hospitality | 2015 |
| Herkkukuningattaret Oy | Manufacturing | 2024 |
| Hermannin Kulma Forssell ja Aitta-aho Avoin yhtiö | Real estate | 2000 |
| Hermanos Ky | Professional & scientific | 1990 |
| Hertta Talot Oy | Construction | 2019 |
| Hesekiel Oy | Financial services | 2021 |
| HiliMed Oy | Health & social care | 2015 |
| Hilma-Team Oy | Real estate | 1989 |
| Hinauskuljetus J. Palm Oy | Transport & logistics | 2004 |
| Hirviojan Taksipalvelu Oy | Transport & logistics | 2023 |
| HittLab Oy | Wholesale & retail | 2024 |
| Hius- ja kauneushuone Kristalli Oy | Other services | 2014 |
| HiusStudio Lunar Oy | Other services | 2026 |
| Hiusstudio Muoto Oy | Other services | 2021 |
| Hm-Media Oy | Professional & scientific | 1994 |
| Hml Sports Oy | Financial services | 2024 |
| Hml Steak House Oy | Hospitality | 2022 |
| Hoitopalvelu Pirkko Suomela Oy | Health & social care | 2024 |
| Hoivaa & Turvaa Sandi Oy | Health & social care | 2023 |
| Hoivapalvelu Maple Oy | Health & social care | 2020 |
| Holiday Brokers Oy | Financial services | 1990 |
| Holy Lake Real Estate Oy | Real estate | 2011 |
| Homebase Oy | Real estate | 2021 |
| Hotelli Mesku Oy | Hospitality | 2016 |
| Huben auto oy | Wholesale & retail | 2023 |
| Hugo Group Oy | Financial services | 2026 |
| Hugola Oy | Arts & recreation | 2026 |
| Huhtamaki Foodservice Nordic Oy | Manufacturing | 2008 |
| Human Factor Oy Ltd | Professional & scientific | 1990 |
| Humec Oy | Professional & scientific | 2013 |
| Huntelier Oy | Wholesale & retail | 2025 |
| Huolto Rane Oy | Administrative & support | 1992 |
| Huoneistoremontit ja uudisrakennukset Kastinen Oy | Construction | 2004 |
| Hupia Creation Oy | Arts & recreation | 2018 |
| Hymyhoitola Oy | Agriculture & fishing | 1994 |
| Hyperman Oy | Hospitality | 1991 |
| Hyperware Oy | Information & communication | 1993 |
| HyvänToivon Oy | Health & social care | 2016 |
| Hywin Oy | Arts & recreation | 2015 |
| Hyötykiinteistö Oy | Real estate | 1993 |
| Hämeenlinnan Mattoasennus OY | Construction | 2014 |
| Häme 10 Oy | Administrative & support | 2005 |
| HämeBus Oy | Transport & logistics | 2014 |
| Hämedent & Rent Oy | Health & social care | 1997 |
| Hämeen Apuvälinetekniikka Oy | Manufacturing | 2007 |
| Hämeen Asunnot & Kiinteistöt Oy | Real estate | 2015 |
| Hämeen Asuntopalvelut Oy | Real estate | 2024 |
| Hämeen Autoehostus Oy | Other services | 2004 |
| Hämeen Autopiste Oy | Wholesale & retail | 2021 |
| Hämeen Autopörssi Oy | Wholesale & retail | 1993 |
| Hämeen Autosähkö Oy | Wholesale & retail | 2004 |
| Hämeen Autotarvike Oy | Wholesale & retail | 2014 |
| Hämeen CarFix Oy | Other services | 2015 |
| Hämeen Erikoisasennus Ky | Manufacturing | 1991 |
| Hämeen Erikoislääkäripalvelut Oy | Health & social care | 2003 |
| Hämeen Erikoispuusepät Oy | Manufacturing | 2016 |
| Hämeen HKV-Apu Oy | Administrative & support | 1996 |
| Hämeen Hoiva & Hyvinvointi Oy | Health & social care | 2026 |
| Hämeen Huoneistovuokraus Oy | Real estate | 1989 |
| Hämeen Huutokauppalaitos Oy | Wholesale & retail | 1991 |
| Hämeen Intima Oy | Health & social care | 2018 |
| Hämeen Isännöinti- ja taloushallintopalvelut Oy | Real estate | 2022 |
| Hämeen KT-kiinteistöt Oy | Real estate | 1990 |
| Hämeen Kanta Oy | Real estate | 2016 |
| Hämeen Kattopinta Oy | Construction | 1991 |
| Hämeen Kiinteistö- ja Nuorisopalvelut Oy | Health & social care | 2006 |
| Hämeen Kirjanpito Oy | Professional & scientific | 2019 |
| Hämeen Konttoritekniikka Oy | Wholesale & retail | 2021 |
| Hämeen Kopiotalo Oy | Professional & scientific | 1990 |
| Hämeen LVIS-Laitehuolto Oy | Manufacturing | 2008 |