Award Years for Sidewise Awards for Alternate History
| 1990's: | - | - | - | - | - | 1995 | 1996 | 1997 | 1998 | 1999 |
| 2000's: | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 |
| 2010's: | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 |
| 2020's: | 2020 | - | - | - | - | - | - | - | - | - |
| Best Long Form Alternate History | ||
| Win | The Yiddish Policemen's Union | Michael Chabon |
| Nomination | 1945 | Robert Conroy |
| Nomination | Ha'penny | Jo Walton |
| Nomination | Ilario: The Lion's Eye | Mary Gentle |
| Nomination | Mainspring | Jay Lake |
| Nomination | Rome Burning | Sophia McDougall |
| Best Short Form Alternate History | ||
| Win | Quaestiones Super Caelo et Mundo | Michael F. Flynn |
| Win | Recovering Apollo 8 | Kristine Kathryn Rusch |
| Nomination | "Les Innocents/Lumiere" (A Chapter in Fix-up Novel New Amsterdam) | Elizabeth Bear |
| Nomination | An Alternate History of Chinese Science Fiction | Jess Nevins |
| Nomination | Metal Dragon Year | Chris Roberson |
| Nomination | Missives from Possible Futures #1: Alternate History Search Results | John Scalzi |
| Nomination | Public Safety | Matthew Johnson |