The Offside Rule in Football, Explained Simply
What Is the Offside Rule in Football? Explained in Simple Words
A clear walkthrough of one of football's most misunderstood rules, based on IFAB's Laws of the Game.
Offside is usually the first rule that confuses new football fans. A good move ends in a goal, the crowd celebrates, then the assistant referee's flag goes up — or VAR steps in — and the goal is cancelled.
The idea behind the rule is straightforward: an attacker shouldn't be able to camp out near the opponent's goal and wait for an easy pass ahead of the defence. The confusion is almost always in the detail of how the moment is judged, not the principle itself.
Standing in an offside position is not itself an offence. A player only gets penalised once they become involved in the play.
The official rule, simplified
Under Law 11 of the Laws of the Game, a player is in an offside position if, at the moment a teammate plays the ball, they are in the opponent's half and closer to the opponent's goal line than both the ball and the second-last opponent.1
Offside position, in short
A player is in an offside position when, at the moment the ball is played:
- They are in the opponent's half.
- They are ahead of the ball.
- They are ahead of the second-last opponent.
Being in that position isn't an offence by itself — it only becomes one if the player then gets involved in the play.
The moment that matters is when the teammate plays the ball — not where the attacker ends up a second later. That single detail is why a goal can look completely normal live and still get overturned on review.
Why "second-last opponent," not "last defender"
Fans often say a player has to stay behind "the last defender," but the Law actually refers to the second-last opponent — and that includes the goalkeeper.1
Usually the goalkeeper is that last line, which is why the shorthand sticks. But if the goalkeeper pushes forward or is out of position, an outfield defender becomes the last opponent instead, and the offside line shifts accordingly.
Quick way to picture it:
Count the opponents between the attacker and the goal line at the moment of the pass. Two or more, and the attacker is onside. Only one, and they may be offside.
When a player is not offside
A few situations are explicitly not offside under the Law:1
Level with the second-last opponent
Being exactly level — not ahead — is onside.
Behind or level with the ball
If the attacker is behind or level with the ball when it's played, they cannot be offside from that pass.
In their own half
A player can never be offside while in their own half when the ball is played.
Direct from a throw-in, corner, or goal kick
There is no offside offence when the ball is received directly from any of these restarts — which is why attackers can stand high during them without a flag.
Don't judge offside from where the striker is when they score. Rewind to the exact moment the pass left their teammate's foot — that's the only moment that counts.
Being offside isn't always punished
This is what trips up most new fans: a player can be in an offside position without the referee stopping play. The offence only applies once that player becomes involved in active play, which under the Law means they:1
- Touch or play the ball a teammate passed.
- Challenge an opponent for the ball.
- Clearly block an opponent's line of vision.
- Interfere with an opponent's ability to play the ball.
- Get the ball after it rebounds off a post, crossbar, the referee, or an opponent.
So a player can be standing offside, stay out of the play entirely, and nothing gets called.
A simple example
Team A is attacking. Player 1 has the ball in midfield; Player 2 is already making a run in behind. At the exact moment Player 1 plays the pass, Player 2 is ahead of the second-last defender and closer to goal than the ball — that's an offside position.
If Player 2 goes on to receive that pass, it's offside. But if Player 2 was level with the defender at the moment of the pass, it's onside — even if they sprint well clear of the defence a second later, because the decision was already locked in when the ball was played.
How VAR and semi-automated offside fit in
Offside is one of the most common reasons a goal gets sent to VAR. Reviewing it means finding the exact frame the pass was made and comparing the attacker's exact position to the defender's at that instant — margins can come down to centimetres.
Many top competitions, including the Premier League since April 2025, now use semi-automated offside technology (SAOT) — tracking cameras and a sensor in the ball — to generate that offside line automatically rather than by hand, which speeds up (though doesn't eliminate) these reviews.2 For more on how VAR reviews work in general, see our VAR explainer.
What happens after an offside call
When offside is given, the defending team is awarded an indirect free kick from the spot where the offence occurred. The attacking move is over — even if the ball had already gone in the net.
KickZone Take
Offside feels complicated mainly because it happens in a split second during live play. The underlying idea is simple: watch the exact moment the pass is made, check the attacker's position against the second-last opponent at that instant, and ask whether they went on to affect the play. Once you're watching for those three things, most offside calls stop feeling random.
Frequently Asked Questions
Can a player be offside in their own half?
No. A player cannot be in an offside position while in their own half when the ball is played.1
Can you be offside from a throw-in?
No. There's no offside offence from a throw-in, corner kick, or goal kick received directly.1
Is a player offside if level with the defender?
No. Level is onside — the attacker has to be strictly ahead of the second-last opponent.1
Does the goalkeeper count as a defender for offside?
Yes. The goalkeeper is an opponent like any other, which is why the Law says "second-last opponent" rather than "last defender."1
Why does VAR sometimes cancel a goal for offside?
Because the review finds the attacker was in an offside position at the moment the ball was played and then became involved in the move that led to the goal.
Sources: 1. IFAB, Laws of the Game 2026/27 — Law 11 (Offside). 2. Premier League semi-automated offside rollout, April 2025.
