Kingside castling

Castling is the only move that relocates two of your pieces at once, and the short version is the one you will play most often. For White the king travels from e1 to g1 and the h1 rook to f1; Black does the same on the eighth rank. Whether it is allowed depends on the game's history and on the board right now. History first: if the king has ever moved, or that rook has ever moved, the right is gone for good, even if the piece later returned home. Then the board: the f and g squares must be empty, you cannot be in check, and the king may neither cross nor land on an attacked square. Notice what the list leaves out. The rook may stand on an attacked square, because only the king's path matters. Over the board, take the king first and move it two squares, then finish the move with the rook using the same hand. A player who uses two hands for one move and then presses the clock can be penalized as if the move were illegal. In notation the move is written 0-0, and many players type O-O instead. Once you have castled, the three pawns in front of the king become its shelter, so push them only with a clear reason.

A neighboring idea is King. The king moves one square in any direction or castles, may never be left in check or moved into check, and is never captured, because the game ends when it is checkmated.

Compare it with Rook. The rook moves any number of squares along its rank or file, provided the path is clear, and it takes part in castling alongside the king.

A neighboring idea is Queenside castling. Queenside castling is a move in which the king steps two squares toward the a-file rook and that rook jumps over to the square the king crossed, written 0-0-0 or O-O-O in notation.

Once "Kingside castling" is familiar, the next question is what to work on at your rating, which the improvement plans by rating band answer with game and puzzle data.

Related terms

• Castling

  Castling is a special king move that shelters the king and activates a rook in one turn: the king goes two squares toward an unmoved rook, which then jumps to the king's other side.

• Queenside castling

  Queenside castling is a move in which the king steps two squares toward the a-file rook and that rook jumps over to the square the king crossed, written 0-0-0 or O-O-O in notation.

• King

  The king moves one square in any direction or castles, may never be left in check or moved into check, and is never captured, because the game ends when it is checkmated.

• Rook

  The rook moves any number of squares along its rank or file, provided the path is clear, and it takes part in castling alongside the king.

• Check

  Check is the state of a king that stands attacked by one or more opposing pieces; the player whose king it is must end the attack with the very next move, because no legal move may leave one's own king attacked.

• Illegal move

  An illegal move is one that breaks the rules of how a piece moves or leaves your own king in check; in over-the-board play it is corrected, and a second completed illegal move loses the game.

Guides that go further

• How to choose a chess coach

  What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid.

• How much does chess coaching cost?

  Published rates for private, group and subscription chess coaching, with the source and the date of each.

• The first lesson

  A game review, a read on your level and a written study plan from George Li.

Sources

• FIDE Laws of Chess (effective 1 January 2023), Article 3.8.2, read Oct 21, 2026.
• FIDE Laws of Chess (effective 1 January 2023), Articles 3.8.2.1 and 3.8.2.2, read Oct 21, 2026.
• FIDE Laws of Chess (effective 1 January 2023), Article 7.5.4, read Oct 21, 2026.
• FIDE Laws of Chess (effective 1 January 2023), Appendix C.13.1, read Oct 21, 2026.