En Passant in Chess

The rule in six diagrams

The rule exists for one reason. Before the two-square pawn move was added, a pawn could slip past an enemy pawn without being capturable. En passant keeps the old balance: a pawn cannot use the double step to avoid a capture it would have faced if it had moved one square at a time.

Diagram 1: the chance appears

White has pushed a pawn to e5. Black now plays the d-pawn two squares from d7 to d5, landing right next to the white pawn on e5. The pawn on e5 can capture it as if it had stopped on d6.

Diagram 2: the capture

White takes en passant. The white pawn moves diagonally to d6, the square the black pawn passed over, and the black pawn on d5 is removed from the board, even though White did not land on its square.

Diagram 3: it works for Black too

The rule is the same for both colors. Here a white pawn moves two squares from e2 to e4 and lands next to a black pawn on d4, and Black captures it by moving to e3.

Diagram 4: only on the next move

The right lasts for one move. If White plays a different move first, Black's chance is gone. In the diagram White has already played Nf3, so the pawn on e5 can no longer capture on d6.

Diagram 5: not for single steps

En passant applies only to a pawn that jumped two squares at once. A pawn that reaches the square next to your pawn in two single steps cannot be taken this way, and since it stands beside your pawn and not diagonally in front of it, it cannot be taken at all.

Diagram 6: when it is illegal

A move is never legal if it leaves your own king in check, and en passant has a rare trap. The capture removes two pawns from the same rank at once. If that opens a line to your king, the capture is illegal. In the diagram the white king and a black rook stand on the fifth rank, and bxc6 would take both pawns off that rank at once and expose the king to the rook.

The three conditions

En passant is allowed only when all three of these are true.

1. The enemy pawn has just moved two squares. It must have come from its starting rank and passed over a square that your pawn attacks.
2. Your pawn stands on the right rank. It must be on the fifth rank for White or the fourth rank for Black, directly beside the enemy pawn.
3. You capture on the very next move. After a different move the right is lost for good.

A fourth condition is the usual one for any move: the capture must not leave your own king in check.

How it is written

In notation, an en passant capture is written like an ordinary pawn capture. White's capture in Diagram 2 is written exd6, and some players add "e.p." at the end. A computer or a scoresheet needs no special mark, because the squares make the capture clear.

Mistakes players make

Three mistakes account for most disputes at the board.

• Taking too late. A player notices the chance two moves later and tries to capture. The right was lost and the move is illegal. Look for en passant every time an enemy pawn makes a double step beside yours.
• Forgetting to remove the pawn. A beginner moves the capturing pawn to d6 and leaves the captured pawn on d5. The captured pawn is removed from the square it stands on, not from the one you land on.
• Touch-move confusion. In a tournament, touching a piece obliges you to move it. A player who touches a pawn thinking of en passant and finds the capture illegal must make a different move with that pawn, if it has one. Decide first, then touch.

Why en passant matters in practice

En passant is rare, but it decides pawn endgames and some tactics. In a pawn endgame it can stop a passed pawn that would otherwise slip through, and in the middlegame it can open a file with tempo. A player who has forgotten the rule loses material in the one game in a hundred where it matters, and a player who knows it can use it to win.

The page on how to play chess lists every rule for a new player, and the glossary page for pawn promotion covers the other special pawn rule.

A short history of the rule

The two-square first move for pawns was added to speed up the game. It created a problem: a pawn on its fifth rank could be passed by an enemy pawn that jumped two squares, escaping a capture it would have faced with one-square steps. En passant restored the balance. The capture is optional, it is available for one move only and it is the reason pawn structures in the center can change so quickly.

Seeing the chance in your own games

The best habit is a short question each time a pawn jumps two squares: is it landing beside one of my pawns? If it is, I can take it, and I should check whether I want to. Often the capture opens a file for a rook or removes a defender, and sometimes it is bad because it opens a line to your own king. Ask the question every time, until it is automatic. Players who ask it find en passant opportunities that stronger players use all the time.

Practice

Set up Diagram 1 on a board and play it from both colors until you do it without thinking. Then set up a pawn endgame and try to find a position where en passant changes the result. A teacher can set up the positions that make the rule clear and test you with a few, and a short lesson on the rules saves months of confusion. See the packages below.