Offsetting penalties occur when players on both teams commit a foul on the same play. These penalties then cancel each other out resulting in no change of field position and the down is replayed.
Though this is not the case for all penalties. There are some instances in which some penalties are valued higher than others. This means they do not offset each other.
When Do Penalties Not Offset
Minor vs Major Penalties
One situation in which penalties would not offset occurs when one team commits a major penalty while the other commits a minor.
For example, say one team commits a fifteen-yard penalty such as a personal foul. This foul will take precedent over any five-yard foul that does not create an automatic first down, is not a spot foul, or loss of down.
This means that if these two fouls meet these criteria the five-yard penalty will be disregarded and the fifteen-yard penalty will be enforced.
If your coach uses more timeouts than he has he will receive an automatic five-yard penalty. This means even if the other team commits a penalty at the same time they do not offset.
Penalties Before A Turnover
One more instance in which offsetting penalties will not occur is during a turnover. If the team that recovers the ball and takes possession has committed a penalty before the turnover occurred then they will not maintain possession of the ball even if the other team committed a penalty.
But if the penatly is committed by the offense during the play and the penalty on the defense is a dead ball foul AKA after the play. Then the defense will still receive possession of the ball.
This is because a penalty during the play may have affected the ability of the offense to maintain possession of the ball. While a penalty after the play has no effect on the turnover occurring or not.
Example: A quarterback throws a deep ball to his possession receiver but there is a hold on the offense. The defensive player pulls the receiver from the hips allowing the defender to intercept the ball.
Despite two penalties happening the turnover will not count because it occured after the penalty.
If the defender intercepted the ball then got a taunting penalty after the play it would be different. The penalties would not offset and the defense would start fifteen yards back from where they intercepted the ball.