There are many penalties in rugby. These penalties can change the game quickly. If a team is responsible for a penalty, the opposing team is given possession of the ball. Many times the team that was not responsible for the penalty is able to kick a goal in what is commonly referred to as the penalty goal.

Rugby Union and rugby league have their own unique sets of penalties. This can make watching or playing one style quite different from the other. These differences are often the reasons that one person prefers one style of rugby from another.

Common penalties for rugby union include entering a ruck from the side of the field, tackling an opponent player that does not have control of the ball, head-butting opponent players, Using inappropriate language when speaking to or about the referee, knocking a ball out of play and high tackles. There are also many more that are not mentioned here. Many times these are not made into offences by referees if the referees believe that the players did not purposely commit them.

Common penalties for rugby league include high tackles, midair tackles, crossing a goal line, hitting a player after they have passed the ball and are no longer in control and offside penalties. There are fewer penalties for the league play, but are often more strictly penalized in comparison with union style.

Both the rugby union and league styles games may look similar at first glance. The players often wear the same types of rugby boots and compression shorts, but it will not take long for an audience to spot differences in playing styles and penalties called by referees.