| K Bros Games | United States | — | 1 | 1 |
| K-D Lab | Russia | 1995 | 7 | — |
| K. Amusement Leasing Co. | Japan | 1972 | 1 | 1 |
| Kabam | United States | 2006 | 2 | 2 |
| Kadokawa Corporation | Japan | 2014 | — | — |
| Kadokawa Games | Japan | April 2009 | 2 | 11 |
| Kadokawa Key-Process | Japan | 1954 | 5 | 2 |
| Kadokawa Shoten | Japan | November 10, 1945 | 3 | 16 |
| Kaga Create | Japan | June 22, 1988 | 2 | 5 |
| Kairosoft | Japan | September 2007 | 18 | 18 |
| Kaizen Game Works | United Kingdom | 2018 | 1 | — |
| Kakao Games | South Korea | — | — | 4 |
| Kalisto Entertainment | France | 1992 | 3 | — |
| Kalypso Media | Germany | 2006 | — | 26 |
| Kamibox | Germany | — | 2 | 1 |
| Kaneda Games | Spain | — | 2 | — |
| Kaneko | Japan | June 25, 1980 | 1 | 2 |
| Kaos Studios | United States | 2006 | 1 | — |
| Karoshi Corporation | Spain | 2003 | 1 | — |
| Kasulo Game Studio | Brazil | 2017 | 1 | — |
| Katauri Interactive | Russia | 2004 | 2 | — |
| KAZe | Japan | 1987 | 1 | — |
| KCET | Japan | — | 1 | — |
| Keen Games | Germany | 2005 | 1 | — |
| Keen Software House | Czech Republic | 2010 | 2 | 1 |
| Kemco | Japan | 1984 | 11 | 59 |
| KeokeN Interactive | Netherlands | 2013 | 2 | 1 |
| Kerberos Productions | Canada | 2003 | 1 | 1 |
| Kerzoven | Switzerland | — | 1 | — |
| Ketchapp | France | 2014 | 1 | 1 |
| Key | Japan | July 21, 1998 | 15 | — |
| Killerfish Games | Australia | — | 1 | 1 |
| Kiloo | Denmark | 2000 | 2 | 1 |
| King | Malta | August 2003 | 7 | 4 |
| King Art Games | Germany | 2000 | 2 | — |
| King's International Multimedia Co., Ltd. | Taiwan | 1980 | — | 2 |
| Kingsoft GmbH | Germany | 1983 | 1 | 3 |
| Kinotrope | Japan | December 1993 | 1 | — |
| KISS | United Kingdom | — | — | 7 |
| KITERETSU | Japan | — | 1 | 1 |
| Kitfox Games | Canada | — | 1 | 5 |
| Kiwiwalks | South Korea | — | 6 | 2 |
| Kixeye | United States | 2007 | 1 | 1 |
| KLab | Japan | August 2000 | 4 | — |
| Klabater | Poland | 2016 | 4 | 19 |
| Klei Entertainment | Canada | July 2005 | 3 | 2 |
| KnowWonder | United States | 1996 | 4 | — |
| Koalabs | France | 2011 | 1 | — |
| Kodansha | Japan | November 1909 | 1 | 2 |
| Kodo Linija | Lithuania | December 4, 2019 | 1 | 1 |
| Kodots Games | Myanmar | — | 2 | 1 |
| Koei | Japan | July 25, 1978 | 49 | 54 |
| Koei Tecmo America | United States | 2010 | — | 4 |
| Koei Tecmo Europe | United Kingdom | August 8, 2002 | — | 2 |
| Koei Tecmo Games | Japan | 2011 | 32 | 65 |
| Koei Tecmo Holdings | Japan | 2009 | 33 | 37 |
| Koei Tecmo Singapore | Singapore | August 2004 | 1 | — |
| Kogado Studio | Japan | 1916 | 8 | 7 |
| Komar Games | Ukraine | June 15, 2010 | 1 | — |
| Konami | Japan | March 21, 1969 | 349 | 424 |
| Konami Computer Entertainment Japan | Japan | April 1996 | 3 | — |
| Konami Computer Entertainment Osaka | Japan | April 1995 | 2 | — |
| Konami Digital Entertainment | Japan | March 31, 2006 | 14 | 21 |
| Konami Digital Entertainment, Inc. | United States | 1982 | 1 | — |
| Konfa Games | Russia | — | 2 | 1 |
| Kongregate | United States | 2006 | — | 2 |
| Koninklijke Philips NV | Netherlands | May 15, 1891 | — | 7 |
| KORION | Germany | — | — | 1 |
| Korkeken Interactive Studio | Sweden | November 18, 1994 | 4 | 1 |
| Koryo Tours | — | 1993 | — | 1 |
| Kotobuki System | Japan | 1984 | 1 | — |
| KR Games | Italy | 2016 | 1 | 1 |
| Krafton | South Korea | March 26, 2007 | 2 | 5 |
| Krea Medie | Denmark | — | 10 | 24 |
| Kremlingames | Commonwealth of Independent States | 2014 | 2 | 2 |
| Krillbite Studio | Norway | August 23, 2011 | 1 | 1 |
| Krisalis Software | United Kingdom | 1987 | 8 | 1 |
| Kritzelkratz 3000 GmbH | Germany | — | 1 | — |
| Krome Studios | Australia | 1999 | 9 | — |
| Krome Studios Melbourne | Australia | 1977 | 15 | 1 |
| Kronos Digital Entertainment | United States | 1993 | 2 | — |
| Kuju Ltd. | United Kingdom | 1998 | 10 | — |
| Kuma Reality Games | United States | 2003 | 1 | 1 |
| Kunos Simulazioni | Italy | 2005 | 3 | 2 |
| Kuro Games | People's Republic of China | 2017 | 2 | 2 |
| Kutoka Interactive | — | — | 4 | — |
| Kuusoukagaku | Japan | July 29, 1991 | 2 | — |
| Kwalee | United Kingdom | 2011 | — | 2 |
| Kylotonn | France | 2002 | 6 | — |
| Kyugo Trading | Japan | — | — | 1 |