Starts with the letter 'S'
- Sankaku Shogi. Small Shogi variant played on a board of 44 triangles with no drops and a teleporting Emperor. (7x8, Cells: 44) By Larry L. Smith.
- Semedo. Missing description (5x8, Cells: 40) Author: Daniil Frolov.
- SerPent Chess 50. Pentagonal cells form hexagonal blocks in two ways. (Cells: 50) By Charles Gilman.
- Shakti. On a 7 by 7 board with disappearing squares. (7x7, Cells: 49) By Christian Freeling.
- Shifting Sands Chess. Special squares -- which can be dropped and moved -- change the types of pieces that land on them. (6x7, Cells: 42) By Tony Quintanilla.
- Shogi 59. Shogi on half of a 9x12 board. (9x13, Cells: 59) By John Smith.
- Sideways Hourglass chess. Small variant on 6 by 7 board with two squares punched out. (7x6, Cells: 40)
- Sigma 4 Shogi. Missing description (7x7, Cells: 49) By Daniel Roth.
- A Silly 42-Squares Board. A Silly 42-squares board with a little Unirexial variant you can play on it. (Cells: 42) By Jared B. McComb.
- Slide-Chess. Variant on 44 squares with moving cages. (7x8, Cells: 44) By João Pedro Neto.
- Small Spherical Chess. Board of form of sphere, with 38 squares. (Cells: 38) By Andrea Mori.
- Small-Deacon Chess. Missing description (7x7, Cells: 49) By (zzo38) A. Black.
- Smallest possible 2D and 3D chess. Missing description (2x2x2, Cells: 4) By Daniil Frolov.
- Smegi. Arrows on squares show where pieces can go - crossover between Smess and Shogi. (5x8, Cells: 40) By Fergus Duniho.
- Snake Chess. A variant played on a 2 by 12 cyclindrical board. (2x12, Cells: 24) By Sergey Sirotkin.
- Snark Hunt. Variant with unequal armies on board with 41 squares, inspired by a poem of Lewis Carroll's. (6x8, Cells: 41) By Peter Aronson.
- SpaceWarp44. 44 square board has warp squares that allow a teleport to another warpsquare. (5x9, Cells: 44) By Jeff Rients.
- Spartan Chess 28. Missing description (4x7, Cells: 28) By Graeme C Neatham.
- spIndecision Beryl. Two players fight with three armies on board formed by 39 triangles. (Cells: 39) By Alexandre Muñiz.
- String Chess. A one-dimensional variant with a fairy theme. (1x24, Cells: 24) By Aaron Hall.
- Subatomic Chess. Missing description By Daniel Robert MacDuff.
- Subway Chess. In a turn, player moves first middle subway part of board and then a piece. (7x7, Cells: 41) By Francois Tremblay.
- Suicide Chess. http://www.windowsphone.com/en-us/store/app/suicide-chess-free/b89dc1a3-2d23-410d-b580-aaaff54d81f5. By Freederick .
- Symmetron! 44. Most pieces move orthogonally or diagonally according to situation. (7x6, Cells: 44) By Antoine Fourrière and Roberto Lavieri.
Total items listed: 24