| Whitethorn Games | United States | 2016 | 1 | 13 |
| Whoopee Camp | Japan | 1997 | 2 | 2 |
| Why so serious | Japan | — | 1 | 1 |
| Wicked Witch Software | — | 1999 | 7 | — |
| Wide Right Interactive | United States | 2017 | 3 | 3 |
| WideScreen Games | France | 1999 | 1 | — |
| Wild River Games | Germany | — | 2 | 5 |
| Wildboy Studios | New Zealand | 2017 | 1 | — |
| WildSphere | Spain | — | 4 | 3 |
| WildTangent | United States | 1998 | 3 | 2 |
| WildWorks | United States | — | 1 | — |
| Will Winn Games | United States | 2020 | 1 | 1 |
| WillPlus. | Japan | August 20, 2010 | 2 | 2 |
| Windmill | Japan | 2002 | 1 | 1 |
| Winkysoft | Japan | 1983 | 7 | 1 |
| Winning Entertainment Group | Japan | October 20, 1987 | 35 | 24 |
| Winter Wolves | Italy | — | 5 | 4 |
| Wired Productions | United Kingdom | May 15, 2008 | — | 7 |
| Wishfully | Sweden | 2018 | 2 | — |
| Witch Beam | Australia | May 15, 2013 | 1 | — |
| WITCHCRAFT inc. | Japan | January 11, 2008 | 1 | — |
| Wizarbox | France | January 31, 2003 | 1 | — |
| Wizard Games | Canada | — | 1 | 1 |
| Wizards of the Coast | United States | 1990 | — | 2 |
| WizardWorks Software | United States | August 21, 1980 | — | 9 |
| WMS Industries | United States | 1974 | 1 | 4 |
| Wobbly Tooth | Japan | — | 5 | 5 |
| Woblyware | Finland | 2009 | 1 | — |
| Wolf & Wood | United Kingdom | January 28, 2015 | 2 | — |
| Wolfire Games | United States | 2003 | 1 | 1 |
| Wolfy | France | October 10, 2018 | 1 | 1 |
| Wonderful Lasers | Canada | November 2014 | 1 | — |
| Wondernaut Studio | Brazil | 2020 | 1 | — |
| WonderPlanet | Japan | September 3, 2012 | — | 1 |
| Wonderscope | Sweden | — | 1 | — |
| Woodland Games | Poland | — | 2 | — |
| Working Designs | United States | 1986 | — | 4 |
| World Food Programme | Italy | December 19, 1961 | — | 1 |
| World Forge | Russia | 2004 | 2 | — |
| World of Wonder | United States | 1991 | — | 1 |
| World's Edge | — | — | 2 | — |
| Worldwalker Games | United States | — | 1 | 1 |
| WorldWideSoftware | Japan | 1996 | 4 | — |
| Wreck Tangle Games | United Kingdom | — | 1 | 1 |
| WSOY | Finland | 1878 | — | 2 |
| X Plus | Japan | 1986 | — | 1 |
| Xaloc Studios | Spain | 2015 | 4 | — |
| XAX Entertainment, Inc. | Japan | April 4, 1996 | 1 | — |
| Xbox Game Studios | United States | March 2000 | 14 | 164 |
| XD | People's Republic of China | 2010 | 2 | 6 |
| Xeen | Japan | July 3, 2006 | 1 | — |
| Xemono | Japan | April 2019 | 1 | — |
| Xform Games | Netherlands | June 28, 2004 | 4 | 2 |
| XGen Studios | Canada | 2001 | 3 | 2 |
| Xigma Games | India | — | 3 | 2 |
| XING | Germany | 2003 | — | — |
| Xitilon | Ukraine | — | 1 | 10 |
| XLGames | South Korea | April 2003 | 4 | 1 |
| XPEC Entertainment | Taiwan | August 2000 | 3 | 1 |
| XS Games | United States | 2002 | — | 2 |
| Xseed Games | United States | 2004 | — | 27 |
| Xtalsoft | Japan | 1982 | 1 | 1 |
| Xuse | Japan | November 1998 | 2 | 1 |
| Yacht Club Games | United States | 2011 | 3 | 3 |
| Yanoman | Japan | December 1959 | — | 1 |
| Yellow Dot | Poland | — | 2 | 2 |
| Yeti | Japan | 2005 | 1 | 2 |
| Yingpei Games | People's Republic of China | September 2006 | 1 | — |
| YipYip | Netherlands | — | 3 | — |
| Yogscast Games | United Kingdom | — | — | 4 |
| Yongshi | People's Republic of China | — | 1 | 1 |
| Yoozoo Games | People's Republic of China | 2009 | 1 | 2 |
| Yostar | People's Republic of China | August 14, 2014 | — | 4 |
| Young Genius | Sweden | — | — | 11 |
| YoYo Games | United Kingdom | 2007 | — | — |
| Ysbryd Games | Wales | 2014 | — | 2 |
| Yuke's | Japan | 1993 | 27 | — |
| Yume Creations | Germany | — | 2 | 2 |
| YumeHaven | Japan | — | — | 1 |
| Yustas Games Studio | Russia | 2011 | 27 | — |
| Yuzusoft | Japan | 2006 | 4 | 3 |
| Z Intermediate Global Corporation | Japan | December 13, 2019 | — | — |
| Z-Software | Germany | 2008 | 5 | 1 |
| Zachtronics | United States | 2011 | 6 | 6 |
| Zeiva Inc | — | — | 3 | 3 |
| Zellers | Canada | 1931 | — | 1 |
| Zemina | — | 1981 | — | 1 |
| Zener Works | Japan | July 1990 | 1 | — |
| ZeniMax Media | United States | May 26, 1999 | — | 1 |
| ZeniMax Online Studios | United States | 2007 | 1 | — |
| ZeptoLab | United Kingdom | 2010 | 6 | 5 |
| Zero | Japan | — | 2 | — |
| Zerocreation Games | People's Republic of China | July 2, 2020 | 2 | — |
| Zerodiv | Japan | August 2007 | 10 | — |
| Zerouno Games | Spain | — | 1 | 4 |
| Ziggurat Interactive | United States | — | — | 36 |
| Zima Software | Czech Republic | 1995 | 6 | 3 |
| Zing Games | United States | 2011 | 1 | — |
| Zipper Interactive | United States | 1995 | 9 | — |
| ZlonGame | People's Republic of China | — | 1 | 2 |