US CHESS
RULES

Making an illegal con be a serious mistake — Do not worry if it happens because it is an honest mistake, but it does have its consequences. US Chess rules allow up to +2 minutes added to the opponent's clock. At Blundercheck, our standard penalty is 30 seconds to 1 minute depending on the time control. If caught, the illegal move must be retracted and a legal move made with the same piece if possible.

Multiple infractions in the same game may lead to automatic loss, depending on the context of the game. Common illegal moves that catch newer players off guard:

• ▸ Moving into check — leaving or putting your own king in check. You cannot make a move that leaves your king attacked.
• ▸ Castling illegally — you can't castle if the king is in check, has previously moved, or if any square between king and rook is attacked or occupied.
• ▸ En passant errors — the en passant capture must be made immediately after the opponent's pawn advances two squares. Wait a move and you lose the right.
• ▸ Moving the wrong piece — once you've touched and moved a piece, that's the piece that moves (touch-move applies).

En passant (French for "in passing") is a special pawn capture that surprises a lot of beginners — and even some intermediate players. It only happens between pawns, and only for one move.

If your opponent advances their pawn two squares from its starting rank and it lands beside your pawn, you may capture it as if it had only moved one square — taking it diagonally and landing on the square it passed through. This option expires immediately: if you don't take en passant on that turn, you cannot take it later.

You are not required to announce "check" in US Chess tournament play — it is polite but not required. Your opponent is responsible for noticing their king is in check and responding.

When checkmated, the game is over. Resigning is also perfectly honorable — simply tip over your king or say "I resign." You do not have to play on in a hopeless position.

Stalemate — if it's your turn to move but you have no legal moves and your king is NOT in check, the game is drawn. This catches many beginners off guard, especially in king-and-pawn endings.

A game can end in a draw several ways. Know them — they matter more than beginners expect.

When a pawn reaches the 8th rank (the far end of the board), it must be promoted to a queen, rook, bishop, or knight. You cannot leave it as a pawn, and you cannot choose not to promote.

You may promote to any piece regardless of how many of that piece you already have on the board — yes, you can have three queens. If you don't have the physical piece, use an upside-down rook as a placeholder and make sure your opponent knows what it represents.

Chess notation is the standard way of recording moves. Each square on the board has a unique name — a letter (a–h) for the file and a number (1–8) for the rank. Moves are written as the piece abbreviation followed by the destination square: Nf3 means knight to f3, e4 means pawn to e4 (pawns have no letter).

Captures are marked with an x (Bxe5 = bishop captures on e5), check with +, and checkmate with #. Castling kingside is O-O, queenside is O-O-O.

♟ CONDUCT AT THE BOARD

Chess is a game of respect. A few things US Chess expects from all players in tournament settings:

• ◻ No phones at the board during tournament play. Silence them and keep them put away.
• ◻ During casual play, friendly conversation is fine. During the tournament, do not discuss any games in progress — including your own — with anyone.
• ◻ When the game ends, shake hands (or fist bump ). Be gracious in both victory and defeat. Every loss is a learning experience
• ◻ Disputes go to the tournament director — not your friends, or other players. We're all here to have a good time and learn so these should be friendly technicalities up for dispute.