Touch-move rule

The touch-move rule in chess specifies that, if a player deliberately touches a piece on the board when it is their turn to move, then the player must move or capture that piece if it is legal to do so. If it is the player's piece that was touched, it must be moved if it has a legal move. If the opponent's piece was touched, it must be captured if it can be captured with a legal move. This is a rule of chess that is enforced in all games played in over-the-board competitions. The player claiming a touch-move violation must do so before making a move.

If a player wants to adjust a piece on its square without being required to move it, the player can announce j’adoube ("I adjust") before touching the piece (Hooper & Whyld 1992:425). A player may not touch the pieces on the board while it is their opponent's turn.

There is a separate rule that a player who lets go of a piece after making a legal move cannot retract the move.

If a player having the move deliberately touches one of their pieces, they must move it if it can be legally moved. So long as the hand has not left the piece on a new square, the latter can be placed on any accessible square. Accidentally touching a piece, e.g. brushing against it while reaching for another piece, does not count as a deliberate touch.

If a player touches a hostile piece, then they must capture it if the piece can be captured. If a player touches one of his pieces and an opponent's piece, they must make that capture if it is a legal move. Otherwise, they are required to move or capture the first of the pieces that they touched. If it cannot be determined whether they touched their own piece or the opponent's piece first, it is assumed that he touched his own piece first. If a player touches more than one piece, they must move or capture the first piece that can be legally moved or captured. An exception to that is an attempted illegal castling; in that case the king must be moved if possible, but otherwise there is no requirement to move the rook.

When castling, the king must be the first piece touched. If the player touches his rook at the same time as touching the king, the player must castle with that rook if it is legal to do so. If the player completes a two-square king move without touching a rook, the player must move the correct rook accordingly if castling in that direction is legal. Otherwise, the move must be withdrawn and another king move made.

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