How Does Offside Work in Football? The Rule Explained

How to judge an offside decision

Find the moment of the pass. Judge the players’ positions when a teammate plays or touches the ball—not when the ball arrives or the receiver controls it.
Check the halfway line. A player cannot be in an offside position while in their own half. The halfway line itself counts as part of that half.
Compare with the ball and opponents. The player must be nearer the opponents’ goal line than both the ball and the second-last opponent. If level with either, the player is not in an offside position.
Ignore body parts that cannot score. Only the head, body and feet count for this position test. Arms and hands are excluded, including those of the goalkeeper.
Ask whether the player becomes involved. Being in an offside position alone is not an offence. The player must interfere with play, interfere with an opponent, or gain an advantage from a rebound or deliberate save.
Restart with an indirect free kick. If the referee judges that an offside-positioned player committed an offence, the opposing team takes an indirect free kick from where the offence occurred.

The basic rule and the offside line

Offside is a rule about a player’s position and involvement in an attack. It is not an offence simply to stand beyond the defenders. The assistant referee and referee assess the position at the instant a teammate plays or touches the ball, then consider what the player does next.

The “second-last opponent” is not necessarily the last outfield defender. The goalkeeper counts as an opponent, but so does every other player on the defending team. The ball may also be nearer the goal line than the second-last opponent: a player level with or behind the ball cannot be offside, even if ahead of the defenders.

Imagine a teammate passing forward while a forward is in the opponents’ half. If the forward is closer to the goal line than the ball and the second-last opponent, the forward is in an offside position. If the forward receives the pass or otherwise becomes actively involved, an offence is likely. If the forward stays out of the play and does not affect an opponent, there may be no offence.

What counts as becoming involved?

The Laws of the Game describe three broad ways a player in an offside position can commit an offence:

Interfering with play: playing or touching the ball passed or touched by a teammate.
Interfering with an opponent: for example, obstructing an opponent’s line of vision or challenging them for the ball.
Gaining an advantage: playing the ball after it rebounds or is deflected from an opponent, goalpost or crossbar, or after an opponent makes a deliberate save.

Being nearby is not automatically enough to count as interference. The referee considers whether the player actually affects an opponent’s ability to play the ball or challenges for it. A player can therefore be in an offside position without a whistle if they do not take part in the relevant action.

When offside does not apply

A player cannot be penalised for receiving the ball directly from certain restarts. The key exceptions are a goal kick, a throw-in and a corner kick. If a teammate subsequently touches or plays the ball, the usual offside assessment applies to later involvement.

There is also an important distinction between a deliberate play by a defender and a deflection or save. If a defender deliberately plays the ball—rather than merely having it rebound off them—an attacker who was in an offside position may generally receive it without being penalised for that position. The referee judges whether the defender had control and the opportunity to play the ball; a mis-kick does not automatically make the action deliberate for this rule. A deliberate save is treated differently: it does not reset the attacker’s offside status.

Common misunderstandings and close calls

“Any forward pass is offside.” False. The direction of the pass is not the test. A player can be onside when a forward pass is played, and an offside-positioned player might be uninvolved in a pass that goes sideways or backward.
“The attacker must be past the last defender.” The comparison is with the second-last opponent, not specifically the last outfield defender. The goalkeeper is included in the count.
“The decision is made when the receiver gets the ball.” No. The relevant snapshot is when the teammate plays or touches it. A receiver may run beyond defenders after that and still be onside if their position was legal at the moment of the pass.
“Being level is offside.” Under the offside-position test, level with the second-last opponent or the ball is onside.

At the top level, assistant referees use the same rule while tracking fast-moving players and passes. Video review, where available, can help examine the relevant positions and involvement, but it does not change the basic test. For ordinary matches, the referee’s decision may depend on a split-second view of the play.

Frequently Asked Questions

Can you be offside in your own half?

No. A player is not in an offside position while any part of their head, body or feet is in their own half, including on the halfway line. The position test only applies in the opponents’ half.

Can you be offside if you do not touch the ball?

Yes, in some situations. A player may commit an offence without touching the ball if they interfere with an opponent, such as obstructing their view or challenging for the ball. Simply standing in an offside position, without becoming involved, is not an offence.

Does the goalkeeper count as the last defender?

The goalkeeper counts as an opponent in the comparison, but the rule refers to the second-last opponent. Depending on where players are, the goalkeeper might be the second-last opponent, the last opponent, or neither.

Can you be offside from a corner or throw-in?

You cannot be penalised for being offside when you receive the ball directly from a corner kick or throw-in. The same exception applies to a goal kick. Normal offside rules can apply after another teammate plays the ball.

What happens after an offside offence?

The defending team receives an indirect free kick from the place where the offside offence occurred. The referee signals the decision, and play restarts with that free kick.

Sources: The IFAB Laws of the Game. Menus and buttons can differ slightly by version. Spotted something out of date? Tell us.