Sooner or later, every chess player meets en passant for the first time — usually when an opponent captures a pawn in a way that looks completely illegal. The pawn that "should" be on d5 vanishes, and the capturing pawn lands on d6, a square nobody was standing on. It feels like cheating. It isn't: it's one of the oldest special rules in chess, and once you know the three conditions, it becomes one of the simplest.
En passant is French for "in passing". The name describes exactly what happens: a pawn that tries to slip past an enemy pawn by moving two squares can be captured as it passes.
The rule in one sentence
When a pawn moves two squares forward from its starting square and lands directly beside an enemy pawn, that enemy pawn may capture it as if it had moved only one square — but only on the very next move.
The three conditions
All three must be true:
- The capturing pawn is on its fifth rank. For White that is the 5th rank; for Black it is the 4th rank.
- The captured pawn has just moved two squares from its starting position and landed on an adjacent file, right next to the capturing pawn.
- The capture happens immediately. If you play any other move first, the right to capture that pawn en passant is gone forever.
And one restriction that surprises nobody once it's said out loud: only pawns can capture en passant, and only pawns can be captured en passant. A knight or bishop can't do it, and a pawn can't capture a piece this way.
An example for White
Notice where the white pawn ends up: d6, the square the black pawn skipped over, not d5 where it actually stood. This is the single most common mistake people make when executing the capture over the board.
An example for Black
Why the rule exists
Pawns originally moved only one square at a time. The two-square first move was added centuries ago to speed up the opening. But it opened a loophole: a pawn could now hop past a square controlled by an enemy pawn and escape capture entirely.
En passant closes that loophole. If the pawn had moved just one square, it would have landed on a square the enemy pawn attacks and could have been taken. En passant says: moving two squares doesn't let you dodge that. Understanding the reason makes the rule easy to remember — it only applies when the double step skips over a square the enemy pawn controls.
How to write it
In algebraic notation, en passant is written like any pawn capture: file of departure, "x", destination square. The example above is exd6. Some players add "e.p." — exd6 e.p. — for clarity, but it's optional. If notation is still new to you, see how to read chess notation.
In a FEN string (the one-line description of a position), the fourth field records the en passant target square right after a double pawn move — for example "d6". That's how software knows whether the capture is legal in a given position.
The edge cases
Two single steps don't count
If Black plays d7–d6 and later d6–d5, landing next to White's e5 pawn, there is no en passant. The rule applies only immediately after a two-square move.
Wait one move and it's gone
Black plays d7–d5. White makes some other move. Black moves. Now White wants exd6 — not allowed. The window is exactly one move wide.
It can be the only legal move
If you're in check and the en passant capture is your only way out, you must play it. It's a normal legal move in every respect.
It can be illegal because of a pin
This is the rare one that even strong players forget. En passant removes two pawns from the same rank at once. Occasionally that opens a line to your own king.
It's never compulsory
Chess has no "must capture" rule. If you have an en passant capture available but a better move elsewhere, play the better move.
When should you capture en passant?
Treat it like any other pawn capture and ask whether it helps you:
- Capture when the double step was meant to create a passed pawn or open lines for the opponent's pieces, and taking stops that plan.
- Think twice when the capture changes your pawn structure badly — for example, creating doubled or isolated pawns. Our guide to pawn structure basics explains which structures are weak and why.
- Skip it when there's a stronger move: a check, a tactic, or a key developing move.
Why people argue about it
In casual games, en passant causes more disputes than any other rule, for two reasons. First, many people learned chess from a friend or relative who didn't know the rule, so it was never part of their game. Second, the capture happens on an empty square, so it genuinely looks like a mistake unless you know what to look for.
If you're playing someone who hasn't seen it before, the kindest approach is to explain it before the game — or to show the example above on the board. Checking the official rules together settles it quickly; en passant has been part of the standard rules of chess for a very long time.
Practicing the rule
The fastest way to lock it in is to set it up yourself: put a white pawn on e5, a black pawn on d7, push the black pawn two squares, then capture. Repeat with Black's pawn on the 4th rank. Twice is usually enough.
The board on our play page applies en passant correctly: when the capture is legal, the target square lights up as soon as you touch the pawn. Play a few games against the computer and it will come up sooner than you expect. For the other special moves, see castling rules and the rest of the rules section.
Frequently asked questions
Is en passant mandatory?
No. It's an option, not an obligation — unless it happens to be your only legal move.
Can pieces other than pawns capture en passant?
No. Only a pawn can capture en passant, and only a pawn that has just made a two-square move can be captured this way.
Can I capture en passant a move later?
No. The right exists only on the move immediately after the double step.
Why won't the app let me capture en passant?
Usually one of the conditions isn't met: the opponent's pawn moved one square twice, you already played a different move, or the capture would leave your own king in check.
Is en passant used at the top level?
Yes, regularly. It's a normal part of pawn play in openings and endgames alike, and strong players take it into account whenever a pawn reaches the fifth rank.
