Domestic association football season

As a rule, the period of the domestic football season is ultimately dictated by the weather, with most football games played on natural grass pitches which are vulnerable to freezing or becoming water-logged, although advances in artificial turf and pitch drainage/heating systems have improved pitch availability in many leagues.

Major League Soccer (MLS), which began in the United States and has since expanded into Canada, has had to compete with American football from its inception, and now competes with Canadian football as well.

The domestic season is preceded by a pre-season, in which clubs will require players to report back to the club by a set date to begin pre-season training, and will arrange pre-season friendly games toward the start of the season to improve fitness and test team formations and tactics, particularly if new playing staff have joined a club.

For dates which fall within a country's domestic season, league clubs are required to release any called up player for their international team a set number of days before a fixture.

The date of the worldwide national team competition the FIFA World Cup is always in June/July, with the exception of the 2022 Qatar edition which was played in November/December.