The National Premier League South Australia 2018 season was the sixth edition of the NPL SA as the premier domestic association football competition in South Australia (and second level within Australia overall). 12 teams took part, all playing each other twice for a total of 22 rounds.
^Following a sanction by the independent Disciplinary Committee, Adelaide City had 18 competition points removed for the 2018 season, and a further 6 points for the 2019 season.[1]
The 2018 SA State League 1 was the sixth edition of the NPL State League 1 as the second level domestic association football competition in South Australia (and third level within Australia overall). 12 teams competed, all playing each other twice for a total of 22 rounds.
The 2017 SA State League 2 was the second edition of the new NPL State League 2 as the third level domestic association football competition in South Australia (and fourth level within Australia overall). 12 teams competed, all playing each other twice for a total of 22 rounds.
The highest tier domestic football competition in South Australia for women was known for sponsorship reasons as the PS4 Women's National Premier League. This was the third season of the NPL format. The 8 teams played a triple round-robin for a total of 21 games.