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Law 7 – The Duration of The Match
Periods of Play
 
  • The match lasts two equal periods of 45 minutes, unless otherwise mutually agreed between the referee and the two participating teams.

  • Any agreement to alter the periods of play (for example to reduce each half to 40 minutes because of insufficient light) must be made before the start of play and must comply with competition rules.
Half-Time Interval
 
  • Players are entitled to an interval at half-time.

  • The half-time interval must not exceed 15 minutes.

  • Competition rules must state the duration of the half-time interval.

  • The duration of the half-time interval may be altered only with the consent of the referee.
Allowance for Time Lost
  Allowance is made in either period for all time lost through:
  • substitution(s);

  • assessment of injury to players;
more on The Duration of The Match