| S2 Games | Kalamazoo | 2003 | video game industry |
| Sabec Limited | — | 1993 | — |
| Saber Interactive Porto | Vila Nova de Gaia | 2008 | video game industry |
| Sacnoth | — | April 30, 1997 | video game industry |
| Sad Panda Studios | Kelowna | 2015 | video game industry |
| Safari Games | — | — | video game industry |
| Saffire | American Fork | 1993 | video game industry |
| Sakari Games | Antwerp | — | — |
| Sakata SAS Co., Ltd. | — | 1985 | video game industry |
| SakuraGame | Chengdu | — | video game industry |
| Salix Games | Guildford | April 2016 | — |
| San Diego Studio | San Diego | 2001 | video game industry |
| Sandlot | Suginami | March 12, 2001 | video game industry |
| Sandlot Games | Seattle | 2002 | video game industry |
| Sanrio | Shinagawa | August 10, 1960 | wholesale |
| Sanritsu Denki | — | — | video game industry |
| Santa Entertainment | — | 1997 | — |
| Santa Monica Studio | Playa Vista | 1999 | video game industry |
| Santa Ragione | Milan | June 21, 2010 | video game industry |
| Sanuk Games | Pak Kret | 2003 | video game industry |
| Sanyo | Osaka | February 1947 | video game industry |
| Sanzaru Games | Foster City, California | 2007 | video game industry |
| Sapphire Dragon Productions | Melbourne | — | video game industry |
| SAS Sakata | — | — | video game industry |
| Saturn-plus | Voronezh | 1997 | — |
| Savage Entertainment | Los Angeles | 1997 | video game industry |
| SCE Studio Liverpool | Liverpool | 1984 | — |
| Scetlander Ltd. | — | — | — |
| Scholastic Corporation | Scholastic Building | 1920 | — |
| Scitron & Art Inc. | — | 1988 | — |
| Scopely | Los Angeles | 2011 | video game industry |
| Screen Burn | Glasgow | 2015 | — |
| Screenlife Games | — | 2002 | — |
| Scriptwelder Studio | — | — | video game industry |
| SCS Software | Prague | 1997 | video game industry |
| Scythe Dev Team | — | 2017 | video game industry |
| SeaCorpTech | — | — | — |
| Seaven Studio | Tourcoing, Marcq-en-Barœul | February 25, 2013 | IT systems and software consulting |
| Second Impact Games | Brighton | 2011 | — |
| Second Maze | Amsterdam | — | video game industry |
| SEGA Europe | Brentford | 1986 | — |
| Sega Fave | Tokyo | April 1998 | video game industry |
| Sega of America | Irvine | March 10, 1986 | video game industry |
| Sega Racing Studio | Solihull | 2005 | — |
| Sega Sports R&D | Japan | 1994 | video game industry |
| Sega Wow | Ebisu | 2003 | video game industry |
| Seibu Kaihatsu | Tokyo | 1982 | video game industry |
| Sekai Project | Norwalk, Los Angeles | 2007 | video game industry |
| Selen | — | — | video game industry |
| Senile Team | Dordrecht | 2003 | video game industry |
| Sennep Games | — | — | — |
| Sensory Sweep Studios | Salt Lake City | 2003 | video game industry |
| SFB Games | London | September 2, 2002 | — |
| Shall Luck Plus | — | 2002 | video game industry |
| Sharkmob | Malmö | 2016 | video game industry |
| Shedworks | — | — | — |
| Shift | Fujisawa | June 1999 | video game industry |
| Shift Up | Seoul | December 2, 2013 | video game industry |
| Shimada Kikaku | — | — | video game industry |
| Shiravune | — | 2019 | video game industry |
| Shiver Entertainment | Miami | 2012 | video game industry |
| Shiver Games | Helsinki | 2010 | video game industry |
| Shockwave | — | — | video game industry |
| Shogakukan-Shueisha Productions | Jinbōchō | June 26, 1967 | service sector |
| Sickhead Games | Dallas | October 2002 | video game industry |
| Sierra Europe | — | — | — |
| Silmarils | Lognes | October 16, 1987 | video game industry |
| Silver Bullet | Tokyo | — | — |
| Silver Lining Interactive | Chelford | July 16, 2024 | — |
| Silver Style Entertainment | Berlin | 1993 | video game industry |
| Silverball Studios | Burford | 2002 | — |
| Silverbyte | — | — | video game industry |
| SilverStarJapan Co., Ltd. | Gifu Prefecture | June 11, 1997 | — |
| Simrail S.A. | — | — | video game industry |
| SIMS Co., Ltd. | Tokyo | June 12, 1991 | video game industry |
| Simutronics | St. Louis | 1987 | video game industry |
| SingleTrac | Salt Lake City | 1995 | video game industry |
| Sir-Tech | Ogdensburg | 1979 | video game industry |
| Sirlin Games | Emeryville | 2005 | video game industry |
| Size Five Games | — | 2008 | — |
| Sketchbook Games | Colchester | December 13, 2016 | — |
| Skunkape Interactive | — | — | video game industry |
| Skybound Entertainment | Beverly Hills | 1992 | comics industry |
| Skybound Games | — | — | video game industry |
| Skydance TV | New York City | June 25, 1984 | media industry |
| SkyFallen Entertainment | Voronezh | 2002 | video game industry |
| SkyTale Software GmbH | Vienna | — | video game industry |
| Slant Six Games | Vancouver | 2005 | video game industry |
| SleepTeam | Dolní Město | 1996 | video game industry |
| Slightly Mad Studios | London | 2009 | — |
| Slipgate Ironworks | Aalborg | 2010 | video game industry |
| Slug Disco | Liverpool | January 27, 2014 | — |
| Sluggerfly | — | — | video game industry |
| SMAC Games | — | — | — |
| Small Giant Games | Helsinki | 2013 | mobile game |
| Smart Tale | — | — | video game industry |
| Smartmelon Games | — | — | video game industry |
| SMEE | — | — | video game industry |
| SMG Studio | Sydney | July 2013 | video game industry |
| SmileBoom | — | January 15, 2008 | — |
| Smilesoft | — | — | video game industry |
| Smug Marmot Studios | Bend | — | — |
| Snail | Suzhou | October 2000 | video game industry |
| Snap Finger Click | Brighton | 2015 | — |
| SNK | Higashiōsaka-shi, Suita | April 1986 | video game industry |
| SNK-Games | — | 2003 | video game industry |
| Snoozy Kazoo | — | May 2020 | video game industry |
| Snow Cannon Games | — | — | video game industry |
| Snowblind Studios | Kirkland | 1997 | video game industry |
| So Romantic | Taipei | 2012 | — |
| Soaphog Game Studio | — | 2016 | video game industry |
| Soedesco | Rotterdam | 2001 | video game industry |
| Soft Machine | — | — | video game industry |
| Softgold Computerspiele | Kaarst | 1986 | video game industry |
| SoftLab-NSK | Novosibirsk | 1988 | — |
| Softmax | South Korea | October 28, 1994 | video game industry |
| Softstar Technology (Beijing) | — | — | video game industry |
| Softstar Technology (Shanghai) Co., Ltd. | — | June 14, 2001 | video game industry |
| Software Creations | Manchester | 1985 | video game industry |
| Software Projects | Woolton | 1983 | video game industry |
| Sokaikan | London | September 18, 2017 | — |
| Solar Software | — | — | — |
| Sometimes You | — | — | video game industry |
| SomniumSoft | Val Gardena | — | video game industry |
| Sonic Powered | Nagoya | April 1998 | video game industry |
| Sonic Team | Tokyo, Novosibirsk | 2000 | video game industry |
| Sonka | — | — | — |
| Sonnori | Gyeonggi Province | February 1998 | video game industry |
| Sony Group | Minato | May 7, 1946 | video game industry |
| Sony Pictures Digital | Culver City | 1997 | entertainment |
| Sony Pictures Mobile | — | — | video game industry |
| SoulGame Studio | Toulouse | December 16, 2019 | video game publishing |
| Source Research & Development | — | — | — |
| Southend Interactive | Malmö | — | video game industry |
| Southern Create | — | — | video game industry |
| SouthPAW Games | — | — | video game industry |
| Space Lizard Studio | — | — | — |
| Spark Unlimited | Los Angeles | 2002 | video game industry |
| Sparklers | — | — | — |
| Sparkling Society | Delft | 2013 | mobile game |
| Spearhead Games | Montreal | 2012 | video game industry |
| Special FX Software | — | — | — |
| Spectrum HoloByte | Alameda | 1983 | video game industry |
| Spellbound Entertainment | Offenburg | 1994 | video game industry |
| Spike Chunsoft | Shinagawa | 2012 | video game industry |
| Spil Games | Hilversum | 2001 | video game industry |
| Spiral Circus | Bristol | October 23, 2018 | — |
| Spiral House | — | 1998 | — |
| Spiral Up Games | — | 2021 | video game industry |
| Spooky Doorway | Galway | — | video game industry |
| Sporty Peppers | Issy-les-Moulineaux | April 16, 2021 | video game industry |
| Springfish Co., Ltd. | — | October 24, 2018 | — |
| Springloaded | — | — | video game industry |
| Sproing Interactive Media | Vienna | 2001 | video game industry |
| Square | Meguro | September 1986 | video game industry |
| Square Enix Business Division 1 | — | December 2013 | video game industry |
| SquarePlay Games | London | November 2015 | — |
| St.GIGA | — | 1990 | satellite radio |
| Stainless Games | Newport | 1993 | — |
| Star Drifters | Warsaw | — | video game industry |
| Starbreeze Studios | Stockholm | 1998 | video game industry |
| Starbyte | — | 1988 | video game industry |
| Starship Group | Liverpool | 2013 | — |
| Starward Industries | Kraków | 2018 | video game industry |
| Starz Entertainment | Santa Monica | April 28, 1997 | show business |
| State of Play | London | 2008 | — |
| Steckenpferd Enterprises UG | Fürth | — | — |
| Steel City Interactive | Sheffield | February 19, 2020 | — |
| Steel Mantis | Texas | — | video game industry |
| Stegosoft Games | Akron | November 14, 2013 | video game industry |
| Stellar Stone | Santa Monica | 2000 | video game industry |
| Step Creative Group | Sinclair | 1994 | — |
| Stern Electronics | Chicago | 1977 | video game industry |
| Sticky Studios | — | — | — |
| Stillalive studios | Innsbruck | 2010 | video game industry |
| Sting | Tokyo | February 7, 1989 | video game industry |
| Stoic | — | — | video game industry |
| Stormfront Studios | San Rafael | 1989 | video game industry |
| Storybird Studio | — | — | video game industry |
| Straight Edge | Chiyoda | April 2016 | — |
| Strange Flavour | United Kingdom | 2004 | — |
| Strange Scaffold | United States | February 12, 2019 | video game industry |
| Strangelite | — | — | — |
| Strategy First | Montreal | 1988 | — |
| Stray Bombay | Seattle | — | — |
| Stray Fawn Studio | Zurich | — | video game industry |
| Streum On Studio | Nogent-sur-Marne | August 2, 2007 | video game industry |
| Studio 1-2 | — | — | — |
| Studio 100 | Schelle | March 29, 1996 | entertainment industry |
| Studio 33 | Liverpool | 1998 | — |
| Studio 9.7 | — | — | video game industry |
| Studio Alex | — | — | video game industry |
| Studio Fizbin | Ludwigsburg | 2011 | — |
| Studio Gamaii | — | — | video game industry |
| Studio Huckepack | Cologne | — | — |
| Studio Nue | Mitaka | 1972 | mass media |
| Studio Saizensen | — | — | video game industry |
| Studio Wildcard | Kirkland | 2014 | video game industry |
| Subelectro Ltd | — | — | video game industry |
| Success | Shinagawa | 1978 | video game industry |
| Summitsoft Entertainment | Omaha | May 3, 1993 | — |
| Sumo Digital | Sheffield | 2003 | — |
| Sumo Nottingham | Nottingham | 2016 | — |
| SunDust | — | — | video game industry |
| Sunflowers Interactive Entertainment Software | Heusenstamm | 1993 | video game industry |
| Sungrand Studios | — | — | — |
| Sunhead Games | Taipei | March 2012 | video game industry |
| Sunna Entertainment | — | 2014 | video game industry |
| Sunnyside Games | Lausanne | 2013 | video game industry |
| Suntendy Interactive Multimedia Co.,Ltd. | Beijing | June 2, 1997 | video game industry |
| Super Evil Megacorp | San Mateo | 2012 | video game industry |
| Super PowerUp Games | Barcelona | — | video game industry |
| Super Rare Games | London | October 25, 2017 | — |
| Super Sly Fox | Dursley | September 18, 2020 | — |
| Supercell | Ruoholahti | May 14, 2011 | video game industry |
| SuperGaming | Pune | 2017 | video game industry |
| Supergiant Games | San Jose | 2009 | video game industry |
| Supergonk | Guildford | — | — |
| Superior Software | Leeds | 1982 | video game industry |
| Supermassive Games | Guildford, Surrey | 2008 | — |
| Supermono studios | London | — | — |
| Supersoft | — | 1978 | — |
| Supersonic Software | Leamington Spa | 1989 | — |
| Supra Games | — | — | video game industry |
| SureAI | Tutzing | 2003 | video game industry |
| Survios | Los Angeles | 2013 | video game industry |
| Suzak Inc. | Tokyo | June 26, 2000 | video game industry |
| SVT Drama | — | 1996 | — |
| Swan | Tokyo | October 5, 1995 | — |
| Sweet Baby Inc. | Montreal | 2018 | video game industry |
| Sweet Bandits Studios | Quebec City | 2016 | video game industry |
| Swisslos | Basel | 1937 | lottery |
| Swordfish Studios | Birmingham | 2002 | — |
| Synapse Software | Richmond | 1981 | video game industry |
| System 3 | London | 1981 | — |
| System Sacom | Tokyo | 1981 | video game industry |
| SystemSoft | Tokyo | September 28, 1979 | — |
| SystemSoft Alpha | Japan | April 1999 | video game industry |