How Does En Passant Work?
En passant (French for "in passing") is chess's most commonly confused rule. Even experienced players sometimes argue about it. Here is the complete, official explanation of how en passant works, when you can use it, and the mistakes players make.
What is en passant?
En passant is a special pawn capture that can only happen under very specific conditions. When an opponent's pawn advances two squares from its starting position, landing beside your pawn, you can capture it as if it had only moved one square. Your pawn moves diagonally to the square the opponent's pawn "passed through".
The three conditions
For en passant to be legal, all three conditions must be true:
- The captured pawn must have just moved two squares from its starting position on that very move.
- The capturing pawn must be on its fifth rank (the 5th row for White, the 4th row for Black).
- You must capture immediately on the very next move. If you wait, you lose the right to capture en passant.
This is the most commonly forgotten part: en passant is a now or never opportunity. You cannot capture en passant on a later move.
Why does en passant exist?
En passant was introduced in the 15th century when the two-square pawn advance was added to speed up the game. Without en passant, a pawn could use the two-square advance to "sneak past" an opposing pawn that had advanced to the fifth rank. En passant prevents this bypass, maintaining the pawn's blocking power.
Common mistakes
- Mistake 1: Trying to capture en passant when the opposing pawn moved only one square.
- Mistake 2: Trying to capture en passant a move later (it must be done immediately).
- Mistake 3: Thinking en passant applies to pieces other than pawns (it doesn't).
- Mistake 4: Forgetting that you can be in check after en passant (you cannot make an en passant capture if it would leave your king in check).