What is pass interference in flag football?
I · Intermediate · Contact, blitzing and penalties · 8 of 9Pass interference is contact that hinders an opponent while a forward pass is in the air. It costs 10 yards, with an automatic first down if the defence did it and loss of down if the offence did. Shielding is the no-contact version: moving into an opponent's path to block them off. It costs 5 yards.
How it works
- Pass interference: "contact that interferes with an opponent whilst the ball is in the air".
- When: from the release of a legal forward pass until a player touches it or it falls incomplete.
- Equal rights: both players may go for the ball. A fair, simultaneous attempt by both is not a foul.
- Whose job: the player in the worse position must avoid the opponent.
- Penalty: 10 yards from the basic spot. Automatic first down against the defence, loss of down against the offence.
- Before the throw: contact is illegal contact, with the same penalty.
- After the touch: contact that knocks the ball loose is illegal contact, not interference.
- Shielding: "obstructing an opponent without contact by moving into their path".
- Standing still: a stationary player is not shielding, even if they are in the way.
- Pick plays: a receiver who crosses a defender's lane to cut them off from another receiver is shielding.
- Shielding a blitzer: an offensive player moving into the blitzer's lane.
- Penalty for shielding: 5 yards from the basic spot.
The glossary has pass interference, shielding, illegal contact, the automatic first down, the loss of down and the pass.
Tricky cases
Two receivers cross, and their two defenders run into each other. Foul?
No. The offence is not responsible for what the defenders do, unless a receiver crossed a defender's lane in order to obstruct them.
A defender bumps a receiver on the right while the pass is thrown to the left. Foul?
Yes, illegal contact. It is a foul to contact an opponent whether or not the ball is thrown their way.
A receiver pushes off a defender to get free, catches the pass and scores on fourth down. What is the result?
Offensive pass interference: no score, and the series ends on the loss of down.
The defence interferes in the end zone on a pass from the 13-yard line. Where is the ball placed?
Half the distance to the goal line, at the 6.5-yard line, with a first down.
Why the rule exists
The pass is the heart of the game, so the catch has to be a contest for the ball and not for position. Shielding is banned for the same reason blocking is: an offence that could screen defenders without touching them would bring blocking back by another name.
Where it differs
| Where | What changes | Source |
|---|---|---|
| Contact while the pass is in the air | Pass interference, 10 yards | IFAF Flag Rule 7-3-3 |
| Contact before the pass or after it is touched | Illegal contact, 10 yards | IFAF Flag Rule 9-1-1; AR 7-2-2-V and VI |
| Obstruction without contact | Shielding, 5 yards | IFAF Flag Rule 9-2-2 a |
| Tackle football | A defender may contact a receiver near the line | C |
From the rule book
International Federation of American Football, International Flag Football Rules 2023 (in force from 1 May 2023), Rule 2-11-2, Rule 7-3-3 and Rule 9-2-2, with approved rulings 7-3-3-I to III, 10-3-1-a-II and 10-3-3-II. Checked 14 October 2026. Official document: IFAF International Flag Football Rules 2023 (PDF).