What "offside" actually means
Offside is the most misunderstood law in football, largely because fans use the single word "offside" to describe two different things: being in an *offside position*, and committing an *offside offence*. They are not the same, and the gap between them explains almost every argument you'll ever have about it.
A player is in an offside position if they are in the opponent's half and any part of their head, body or feet is nearer to the opponent's goal line than *both* the ball and the second-to-last opponent (usually the last outfield defender, since the goalkeeper is normally the last). Being level with the second-to-last opponent, or level with the last two opponents, counts as onside.
Position vs. offence — the crucial difference
Here is the part most people miss: being in an offside position is not an offence. A player standing in an offside position commits an offence only if, *at the moment a teammate plays or touches the ball*, they then become involved in active play in one of three ways:
- Interfering with play — playing or touching the ball passed or touched by a teammate.
- Interfering with an opponent — blocking the goalkeeper's line of vision, challenging for the ball, or making an obvious action that impacts an opponent's ability to play it.
- Gaining an advantage — playing a ball that rebounds or is deflected to them off the goalpost, crossbar, a match official, or an opponent's deliberate save.
The timing anchor is everything: offside is judged at the instant the ball is *played by the teammate*, not the instant the attacker receives it. A striker can be onside when the pass is struck and run through — that's not offside, even though they collect the ball level with the goalkeeper.
When you cannot be offside
Several situations rule offside out entirely:
- You cannot be offside in your own half at the moment the ball is played.
- You cannot be offside directly from a goal kick, a throw-in, or a corner kick.
- You are not offside if you are level with the second-to-last opponent — level is onside.
Which part of the body counts
Offside is measured using the parts of the body a player can legally score with: any part of the head, body or feet. The arms and hands are excluded — and for measurement purposes, the "arm" begins at the bottom of the armpit. This is why VAR offside lines are drawn to a shoulder or a knee, never a hand: a goal cannot be scored with the arm, so the arm cannot put a player offside.
Deliberate play vs. deflection
One of the rule's trickiest areas was clarified by IFAB in 2023. If a defender deliberately plays the ball (a controlled pass, clearance or interception) and it reaches an attacker who was in an offside position, that attacker is not penalised — the defender's deliberate action "resets" the phase. But if the ball simply deflects off a defender, or comes off a defender's attempted save, the attacker in the offside position *is* penalised for gaining an advantage. The distinction hinges on whether the defender had control and made a deliberate football action, or was simply reacting.
VAR and semi-automated offside
At the top level, the tightest calls are now settled by semi-automated offside technology (SAOT), used at the 2022 World Cup and again in 2026. Multiple cameras track the ball and dozens of points on each player's body many times per second, generating a near-instant automated offside line and a 3D animation for broadcast. It has sped up decisions and removed most human line-drawing error — but it hasn't ended the debate, because the law still turns on the *exact frame* the ball is played, and "toenail" offsides that overturn goals remain deeply unpopular. IFAB has trialled "daylight" interpretations that would give the attacker the benefit of any overlap, but as of the current Laws, any measurable part of the body beyond the line is offside.
Common misconceptions
- "Level is offside." Wrong — level with the second-to-last defender is onside.
- "Offside is judged when they get the ball." No — it's judged when the *teammate plays* the ball.
- "You can be offside from a corner." You cannot be offside directly from a corner, throw-in or goal kick.
- "He was offside because he was in front of the defender." Only matters if he was *involved in active play* at the moment the pass was made.
- "The arm was past the line, so it's offside." Arms don't count.
Related guides
Frequently asked questions
- Can you be offside from a throw-in?
- No. A player cannot be penalised for offside directly from a throw-in, a corner kick or a goal kick.
- Is being in an offside position a foul?
- No. Being in an offside position is not an offence in itself. It only becomes an offence if the player becomes involved in active play — interfering with play, interfering with an opponent, or gaining an advantage — at the moment a teammate plays the ball.
- Does the arm count for offside?
- No. Offside is measured using the head, body and feet — the parts you can legally score with. The arms and hands are excluded, with the line taken at the bottom of the armpit.
- When exactly is offside judged?
- At the precise moment the ball is last played or touched by a teammate — not when the attacking player receives it.
- Can you be offside in your own half?
- No. A player must be in the opponent's half to be in an offside position.