The main competition, known as the 2018 Telstra Premiership due to sponsorship from Telstra, featured 16 teams playing 25 weekly rounds of matches from March until September, resulting in the top eight teams playing a series of finals matches to determine which two teams reached the 2018 NRL Grand Final.

The 2018 pre-season featured the 2018 World Club Challenge match with the NRL premiers Melbourne Storm defeating the Super League champions Leeds Rhinos.

With the City vs. Country representative game having been scrapped, the NRL scheduled 6 games to take place in regional areas of New South Wales and Queensland as a replacement: Tamworth, Bathurst & Mudgee, and Toowoomba, Gladstone & Cairns.

The second game of the 2018 State of Origin series was played as a stand-alone fixture on a Sunday to avoid conflict with the regular season.

Due to this the competition was shortened to 25 rounds and each team got 1 bye as opposed to 2 in previous years.