Each team is allowed 13 players (who will be registered at the beginning of the competition) with seven (a goalkeeper and six field players) participating at any one time. Substitutions are most common after a goal is scored. Players can also substitute by swimming to their bench corner and tagging an entering player. Players can play up a division for 1 game if necessary.
Players tread water the entire game, and cannot touch the sides of the pool. Except for the goalkeeper, players may handle the ball with only one hand. The referee indicates fouls by blowing a whistle and using hand signals to point out the location of the foul and the attacking direction of the fouled player. A goal (1 point) is scored when the ball is thrown or pushed completely past the face of the goal.
The game is played in 4 quarters, each being 5 minutes in length with a one minute interval. If a team is later then 5 minutes to their game (in the pool with a minimum of 6 players), they will forfeit the game.
A winning team will be awarded 3 points, losing team 1 point. A draw will result in both teams being awarded 2 points, and a forfeit will result in the forfeiting team receiving zero points, their opposition receiving 3. At the end of the competition, the points will be added, and certificates awarded to the first and second team in each division. If there is a draw, there will be a count back based on number of goals scored.
A team can consist of 6 players and 1 goalie. It is permissible for a team to play with 6 players in total. In this instance, they can choose whether to have a goalie or not. If a team has less than 6 players, they are required to negotiate the feasibility of playing a game with the opposition.
Each half is started with the teams lined up on opposite goal lines. On the whistle from the referee, the teams sprint toward centre pool where the referee tosses the ball into the water. The team gaining possession of the ball advances it toward its offensive end of the pool by swimming, dribbling or passing the ball. Caps must be worn at all times when in the pool.
There are two types of fouls in Water Polo. Players are allowed three major fouls before they foul out of the match. Major fouls include exclusion and penalty fouls.
- Ordinary Fouls
- Exclusion Fouls
- Penalty Fouls
Common ordinary fouls include:
- touching the ball with two hands
- taking the ball under water when tackled
- impeding an opponent who is not holding the ball
- pushing off an opponent
When the referee calls an ordinary foul, the offended team is awarded a free throw at the point of the foul. A player cannot shoot the ball on a free throw, unless the foul occurred beyond seven metres away from the goal.
An ordinary foul committed by the defense during dead time (after a foul occurs, but before offended player has put the ball into play):
- interfering with a free throw
- misconduct or disrespect to the referee
- holding sinking or pulling back an opponent not holding the ball
Major Fouls - exclusion fouls
Common exclusion fouls include:
- kicking or striking
- deliberate splashing in the face
Exclusion fouls result in a player being excluded for 20 seconds. The excluded player (or his/her substitute) may not return until a goal is scored, or the referee indicates the player may return.
A player with three major fouls is removed from the game with substitution. Deliberate kicking or striking with intent to injure (brutality) results in ejection of the offending player for the reminder of the game, without substitution.
Penalty Fouls - penalty fouls
Penalty fouls are committed within the four-metre area where a goal probably would have resulted. The offensive player fouled while in control of the ball and facing the goal inside the four-metre line is usually awarded the penalty throw. A penalty foul is recorded against the player committing the foul. any player in the fame from the offended team can take the penalty throw. The shot is taken from the four-metre line, with only the goalie defending.
The award of a penalty throw most commonly occurs in the following situation within the four-metre area:
- any player, including the goalkeeper, pulling down or pushing away the foal
- any player, except the goalkeeper, playing the ball with both hands or a clenched fist
- the goalkeeper or a defensive player taking the ball underwater
- when an offensive player in control of the ball and facing the goal is fouled by holding, sinking or pulling back