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Castling

Castling moves the king and a rook in one turn, tucking the king away and bringing the rook into play. Learn how and when you may castle.

Beginner6 min

Two pieces, one move

Castling is the only move where two pieces move at once. The king steps two squares toward a rook, and that rook jumps to the square on the king's other side. White castles kingside (the short side), then Black castles queenside (the long side).

Two pieces, one move abcdefgh12345678

When you may castle

You may castle only if: the king and that rook have never moved, the squares between them are empty, the king is not in check, and the king does not pass through or land on an attacked square. Here Black's bishop attacks f1, so White cannot castle kingside. Queenside castling is still allowed.

When you may castle abcdefgh12345678

Castle with a bang

Your turn

Castling can even give checkmate. Castle kingside to finish the game.

Show the answer

Castling kingside put the rook on f1 with check, and your king on g1 covers g2 and f2. Black's king has nowhere to go: checkmate.

Castle with a bang abcdefgh12345678

Now the long side

Your turn

Checkmate by castling queenside.

Show the answer

Queenside castling put the rook on d1 with check, and your king on c1 covers c2. Moving the rook to d1 on its own would not be mate, because Black's king could escape to c2.

Now the long side abcdefgh12345678

Quick check

Question

Which of these means you can never castle again in this game?

  • Your king has already moved, even if it went back to its square
  • Your king is in check right now
  • An enemy bishop is attacking your rook
Show the answer

Your king has already moved, even if it went back to its square

Once the king has moved, castling is gone for good, on both sides.

More in Rules

En passant A special pawn capture: when an enemy pawn rushes two squares past yours, you may take it as if it had moved only one. Learn when it's allowed. Check and checkmate When your king is attacked you must save it. Learn the three ways out of check, and how to give a checkmate that ends the game. Stalemate If your opponent has no legal move and is not in check, the game is a draw. Learn to avoid this trap when you are winning. Promotion A pawn that reaches the last rank turns into a queen, rook, bishop or knight. Learn how promotion works and why the queen is usually the choice. The knight The knight jumps in an L-shape and is the only piece that can leap over others. Learn its move and why it hates the corner.