Two-handed move

In over-the-board competitive chess, every move must be played with one hand. A two-handed move occurs when a player divides the physical actions of a single move between both hands.

Typical cases include moving the king with one hand and the rook with the other during castling, the special move that transfers both pieces; removing a captured piece with one hand while moving the capturing piece with the other; or removing the pawn and placing the new piece with different hands during queening or another promotion.

Under the FIDE Laws, if a player uses two hands for one move and then presses the clock, the violation is treated and penalized as a completed illegal move. For the first such completed illegal move, the arbiter normally adds two minutes to the opponent; a second completed illegal move by the same player loses the game unless the opponent cannot checkmate, meaning attack the king with no legal reply, through any series of legal moves.

The position may need position reinstatement, a return to the last identifiable state before the irregularity, before play continues. A separate rule also requires the clock to be pressed with the same hand that made the move. Moving correctly with one hand and pressing with the other is not a two-handed board move, but it still violates the clock-handling rule.