Also included in the 2018 calendar is the Hopman Cup, which is organized by the ITF and does not distribute ranking points.

[1] This is the complete schedule of events on the 2018 calendar, with player progression documented from the quarterfinals stage.

The players/nations are sorted by: The following players won their first main circuit title in singles, doubles, or mixed doubles: The following players defended a main circuit title in singles, doubles, or mixed doubles: The following players achieved their career high ranking in this season inside top 50 (in bold the players who entered the top 10 for the first time): These are the WTA rankings of the top 20 singles players, doubles players, and the top 10 doubles teams on the WTA Tour, at the current date of the 2018 season.

* Assumes undefeated round robin match record.

Following is a list of notable players (winners of a main tour title, and/or part of the WTA rankings top 100 [singles] or top 100 [doubles] for at least one week) who announced their retirement from professional tennis, became inactive (after not playing for more than 52 weeks), or were permanently banned from playing, during the 2018 season: Following are notable players who will come back after retirements during the 2018 WTA Tour season: