| Havana Shisha OY | Other services | 2022 |
| HAVU & Co. Oy | Wholesale & retail | 2021 |
| HBFROMBH Oy | Arts & recreation | 2024 |
| HC Capital Traders Oy | Financial services | 2016 |
| HCC Tradegroup Oy Ab | Wholesale & retail | 1991 |
| HEGLA TaiFin Glass Machinery Oy | Manufacturing | 2009 |
| Helsingin Riippumatto OY | Wholesale & retail | 1986 |
| Helsinki Data Ykkönen OY | Transport & logistics | 2020 |
| Hertarent OY | Construction | 2019 |
| HHC Branding Oy | Professional & scientific | 2023 |
| HJ Cars Oy | Wholesale & retail | 2019 |
| HJT Rakennus Oy | Real estate | 2019 |
| HK Asuntokeskus Oy | Real estate | 2021 |
| Hki Laatutalot OY | Construction | 2013 |
| HKI Pinnoitus Oy | Construction | 2020 |
| HKP-onkologia Oy | Health & social care | 2023 |
| HL Automyynti Oy | Wholesale & retail | 2022 |
| HL Autopart Oy | Wholesale & retail | 2023 |
| HLA Hyvinvointi & valmennus Oy | Administrative & support | 2019 |
| HMJV Invest Oy | Real estate | 2017 |
| Hotsitus OY | Administrative & support | 1992 |
| HP Taksitiimi OY | Transport & logistics | 2018 |
| HPDC Service Oy | Manufacturing | 2024 |
| HPM - Peat oy | Agriculture & fishing | 2020 |
| HSV Urakointi Oy | Construction | 2021 |
| HSV-Kanmer Oy Ltd | Hospitality | 1993 |
| HTA-Data and House LKV Oy | Real estate | 1986 |
| HTP Electric Box OY | Energy | 2020 |
| HUOLETI Oy | Information & communication | 2017 |
| HV Rakennelmat Oy | Construction | 2020 |
| HV-Remonttipalvelu Oy | Construction | 2014 |
| HVAC-Heat Oy | Construction | 2017 |
| Haarlem House of Blues Oy | Hospitality | 2006 |
| Habibi Cafe 2 Oy | Hospitality | 2020 |
| Hafish Oy | Construction | 2024 |
| Haga Trade Oy | Wholesale & retail | 2018 |
| Hagamaster Oy | Manufacturing | 1999 |
| Hagaplan Oy | Wholesale & retail | 2000 |
| Haicrew Oy | Wholesale & retail | 2019 |
| Hair Group Duo Oy | Other services | 2001 |
| Hallelujahkoru Oy | Wholesale & retail | 2023 |
| Hallifix Oy | Other services | 2019 |
| Halofax Oy | Wholesale & retail | 1994 |
| Haminan Satama-Grilli Oy | Hospitality | 1994 |
| Hammaslaboratorio Hedman avoin yhtiö | Manufacturing | 1985 |
| Hammi Group Oy | Information & communication | 2019 |
| Hamnservice Ab HSS | Administrative & support | 1995 |
| Hamus Trans Oy | Transport & logistics | 2005 |
| Han Zheng International Oy | Professional & scientific | 2022 |
| Handcomp Oy | Information & communication | 2018 |
| Handelslaget Westbotnia Osuuskauppa | Transport & logistics | 1921 |
| Hangtong Oy | Hospitality | 2019 |
| Hanna Heikkilä Design Studio Oy | Professional & scientific | 2022 |
| Hannu Honkavaara Oy | Transport & logistics | 1999 |
| Hannu Kari-Consulting Ky | Professional & scientific | 1986 |
| Hannu Virkkala Oy | Wholesale & retail | 1980 |
| Hansana Oy | Hospitality | 2021 |
| Happy Beach Oy | Hospitality | 2021 |
| Happy Break Oy | Hospitality | 2021 |
| Happy Crocus Oy | Professional & scientific | 2023 |
| Happy Trout Oy | Financial services | 2024 |
| Happy to Help Oy | Information & communication | 1989 |
| Harjutuote Ky | Manufacturing | 1990 |
| Harkonsalo & Vesa (H & V) Public Relations Oy | Professional & scientific | 1995 |
| Harmaa Kivi Oy | Other services | 2021 |
| Harmaa Tarjotin Oy | Information & communication | 2021 |
| Harman Finland Oy | Professional & scientific | 1998 |
| Harmonic Audio Solutions osk | Manufacturing | 2020 |
| Harry & Co Oy | Financial services | 2020 |
| Harrys Garage Finland Oy | Wholesale & retail | 1998 |
| Hartolan Pullapaja Oy | Manufacturing | 2018 |
| Hartolan Rakennusteollisuus Ky | Manufacturing | 1981 |
| Hattulan Autopesu Oy | Other services | 2019 |
| Hauhon Tapahtumat Oy | Arts & recreation | 2021 |
| Haukiputaan Autotarvike Ky | Wholesale & retail | 1979 |
| Haukiputaan Ravi Oy | Wholesale & retail | 1974 |
| Hautauspalvelu Nokianvuori Oy | Other services | 1993 |
| Hautaustoimisto Rauha Oy | Other services | 2023 |
| HavsHus Ab | Construction | 1977 |
| Havu Finance Oy | Professional & scientific | 2024 |
| Havuteräs Oy | Wholesale & retail | 2021 |
| Havuvoima Oy | Health & social care | 2023 |
| Hax Oy | Information & communication | 2020 |
| Headline Oy | Professional & scientific | 1984 |
| Hebun Oy | Hospitality | 2006 |
| Heju Invest Oy | Real estate | 2018 |
| Helios Energia Oy | Administrative & support | 2005 |
| Helirakennus Oy | Construction | 2015 |
| Help-Point Oy | Administrative & support | 1993 |
| Helppo Hotelli Oy | Hospitality | 2016 |
| Helsingin Asfaltti ja Katutyö Oy | Construction | 2021 |
| Helsingin Peltisepät Oy | Construction | 2016 |
| Helsingin Saneeraustekniikka Oy | Construction | 2021 |
| Helsingin Saratem Oy | Construction | 2019 |
| Helsingin Sivukonttori Oy | Professional & scientific | 2019 |
| Helsingin Soitinlaite Oy | Manufacturing | 2014 |
| Helsinginseudun LVI-osto- ja myyntiliike Oy | Wholesale & retail | 1981 |
| Helsinki Aerospace Oy | Manufacturing | 2020 |
| Helsinki Fashion Week Oy | Arts & recreation | 2019 |
| Helsinki Rotting Company Oy | Manufacturing | 2020 |