| A Kodinhoito Oy | Administrative & support | 2025 |
| Albert & Robert Oy | Real estate | 2002 |
| Ammattijalkineet Maahiset Oy | Wholesale & retail | 1984 |
| Annie Sun Oy | Construction | 2010 |
| Ansioniemen Sähkö Oy | Construction | 1994 |
| Arctic Fox Oy Ltd | Manufacturing | 2000 |
| Armadillo Oy | Manufacturing | 1993 |
| Arvi-Invest Oy | Real estate | 1994 |
| Asianajotoimisto Legal Gaming Oy | Professional & scientific | 2020 |
| Autokorjaamo T ja P Lahti Ky | Other services | 1995 |
| Autopaja Olkkonen Oy | Other services | 2022 |
| Brothers Collection Brosco Oy | Professional & scientific | 2024 |
| C-master Oy | Construction | 1990 |
| CoEnergy Oy | Energy | 2025 |
| DS Berakot Oy | Construction | 2021 |
| ELF-taksit Oy | Transport & logistics | 2009 |
| Eilesta Oy | Professional & scientific | 2011 |
| Etelä-Hartolan vesiosuuskunta | Water & waste | 2009 |
| Expodos Oy | Health & social care | 1993 |
| FMJ Corporation Oy | Agriculture & fishing | 2019 |
| Felinos Eläinklinikka Oy | Professional & scientific | 2021 |
| Gasthaus Koskenniemi Oy | Hospitality | 1998 |
| Hartotech OY | Mining & quarrying | 2018 |
| HTA-2000 Osakeyhtiö | Manufacturing | 1989 |
| HaaveLoma Oy | Hospitality | 2015 |
| HarBout OY | Transport & logistics | 2019 |
| HartControl Oy | Professional & scientific | 1991 |
| Hartola Golf Oy | Arts & recreation | 1988 |
| Hartola-Forest avoin yhtiö | Agriculture & fishing | 2022 |
| Hartolan Auto Kommandiittiyhtiö | Wholesale & retail | 1980 |
| Hartolan Kumi Ky | Wholesale & retail | 1990 |
| Hartolan Kuningaslämpö Oy | Energy | 1990 |
| Hartolan Metsäkukka Oy | Wholesale & retail | 1988 |
| Hartolan Redem Oy | Other services | 2015 |
| Hartolan Suksee Oy | Manufacturing | 2025 |
| Hartolan Taksipalvelu Oy | Transport & logistics | 1996 |
| Hartolan Vallesmanni Oy | Real estate | 1981 |
| Hartolan Wanhamatkis Oy | Hospitality | 2014 |
| Hartolan rakennus- ja lvi-palvelut Oy | Construction | 2014 |
| Henkilöstöravintolat Pasi Joronen Ky | Hospitality | 2004 |
| Hilppo Oy | Professional & scientific | 1993 |
| Honkapään Sora Oy | Mining & quarrying | 1983 |
| Information Highway House Oy Ltd | Wholesale & retail | 1995 |
| Itä-Hämeen Keilahalli Oy | Arts & recreation | 1993 |
| Itä-Hämeen LVI-Ala Oy | Construction | 1981 |
| JM Rolig Oy | Construction | 1998 |
| JPS Palvelut Oy | Hospitality | 2015 |
| JT-Hiili Ky | Manufacturing | 1993 |
| Jamicam Oy | Wholesale & retail | 1999 |
| Jaristoteles Oy | Professional & scientific | 2020 |
| JeRoKa Oy | Wholesale & retail | 2021 |
| Juntunen Yhtiöt Oy | Financial services | 2025 |
| KH-Print Oy | Manufacturing | 1992 |
| Kaijan Kotikahvila-Myymälä avoin yhtiö | Hospitality | 1995 |
| Kajo Boardroom Oy | Information & communication | 2026 |
| Kari Uustalo Oy | Construction | 2002 |
| Kauno Koskinen Oy | Other services | 1993 |
| Kiinteistö Oy Hartolan Keskustie 52 | Real estate | 1986 |
| Kiinteistö Oy Hartolan Taksi | Real estate | 1990 |
| Kiinteistö Oy Hartolan Yhdystie 5 | Real estate | 1996 |
| Kiinteistö Oy Metsopirtti | Real estate | 2025 |
| Kiinteistö Oy Vasalli | Real estate | 2004 |
| Kiinteistö- ja Toimistopalvelu T Järvinen Oy | Real estate | 1992 |
| Kilpilohi Oy | Agriculture & fishing | 1982 |
| Kilut Oy | Information & communication | 2008 |
| Kivent Oy | Financial services | 2025 |
| Kodin pintakäsittelijät Oy | Construction | 2024 |
| Kommandiittiyhtiö Arvi Aaltonen | Real estate | 1967 |
| Koneistus Suomi Oy | Manufacturing | 1987 |
| Koneurakointi Kaitra Oy | Construction | 2011 |
| Konna Yhtiöt Oy | Professional & scientific | 2025 |
| Korjaus H Pajunen Ky | Construction | 2005 |
| Kuljetus Simo Iitti Ky | Transport & logistics | 2000 |
| Kuljetus ja Jätehuolto Seppo Hynninen Ky | Transport & logistics | 1985 |
| Kuljetusliike Matti Mäkinen Ky | Transport & logistics | 1985 |
| Kuljetusliike Yrjö Erämies Oy | Transport & logistics | 1981 |
| Kuljetuspalvelu Fågel Oy | Transport & logistics | 1992 |
| Kuningaskunnan Herkku Oy | Hospitality | 2022 |
| Kuninkaan Portti Hartola Oy | Hospitality | 1989 |
| Kurenlahti-Koukunniemi vesiosuuskunta | Water & waste | 2005 |
| L&P Trans Avoin yhtiö | Transport & logistics | 2006 |
| Leon Finlandia Oy | Wholesale & retail | 2008 |
| Linna-hotelli Oy | Hospitality | 1990 |
| Lomapa Oy | Other services | 2023 |
| Luomulikka Ky | Arts & recreation | 2008 |
| MM Välikkö Oy | Transport & logistics | 1985 |
| MTU Saattopalvelu Oy | Transport & logistics | 2013 |
| Marako Oy | Wholesale & retail | 2021 |
| Marienkoti Oy | Hospitality | 1995 |
| Metsä VeMa Oy | Agriculture & fishing | 2003 |
| Metsä-Heinikka Oy | Agriculture & fishing | 2009 |
| Metsäkoneurakointi Ossi Huoponen Oy | Agriculture & fishing | 1995 |
| Metsäkuljetus-Hallberg Ky | Agriculture & fishing | 1994 |
| Metsäurakointi Kari Olkkonen Oy | Agriculture & fishing | 1995 |
| Mittakoneistus 2R Oy | Manufacturing | 1994 |
| Multavuori Media Ky | Information & communication | 1998 |
| Murakan vesiosuuskunta | Water & waste | 2008 |
| North Flames Oy | Hospitality | 2019 |
| Obeliksin Kivi & Betoni Oy | Construction | 2010 |
| OivaLogistics Oy | Transport & logistics | 2025 |