| | NOMAM | Germany | Lubeca (Lübeck) | 2014, 2015, 2016, 2017 |
| | Nordlicht | Germany | Bremen | 2015, 2016, 2017, 2018, 2019, 2023 |
| | Outline | Online events, Netherlands | Eersel, Ommen, Willemsoord | 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Online, 2021, 2022, 2023, 2024 |
| | Platariada | Czech Republic (Czechia) | Budweis (České Budějovice) | 2008, 2017 |
| | Prima Aprilis Compo | | | 2015 |
| | Połączone Siły Atarowskie | Online events | — | 2020 |
| | QuaST | Poland | Elblag (Elbląg), Orneta | 1995, 1996, 1997, 1998, 2003, 2004, 2005 |
| | RetroKomp/Load Error | Poland | Gdansk (Gdańsk) | 2013, 2015, 2017 |
| | RETROnizacja | Poland | Pawlowice (Pawłowice) | 4 |
| | Revision | Online events, Germany | Saarbrucken (Saarbrücken) | 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Online, 2022 Online, 2023, 2025 |
| | Riverwash | Poland | Cracow (Kraków), Katowice, Lodz (Łodz), Warsaw (Warszawa) | 2009, 2010, 2011, 2015, 2016, 2017, 2018 |
| | Rush Hours | Poland | Czanstochova (Częstochowa) | 1997, 1998 |
| | Scenery (.pl) | Poland | Podkowa Lesna (Podkowa Leśna) | 1998 |
| | Shadow Party | Online events | — | 2022 |
| | Shadows Copy Party | Poland | Mirow (Mirów) | |
| | Silesian Atari | Poland | Mikolow (Mikołów) | 1995 Open |
| | Silly Venture | Poland | Gdansk (Gdańsk) | 2k, 2k04, 2k10, 2k11, 2k12, 2k13, 2k14, 2k16, 2k17, 2k18, 2k19, 2k20+1 SE, 2k21 WE, 2k22 SE, 2k22 WE, 2k23 SE, 2k23 WE, 2k24 SE, 2k24 WE, 2k25 SE, 2k25 WE |
| | Sommarhack | Sweden | Grado (Grådö) | 2014, 2019, 2023, 2024, 2025 |
| | Sundown | United Kingdom | Budleigh Salterton | 2014, 2016 |
| | SynchroNY | Canada | Montreal (Montréal) | 2016, 2017 |
