The WTA 125 tournaments are the secondary professional tennis circuit organised by the Women's Tennis Association.

The 2021 calendar consisted of fifteen tournaments due to the impacts of the COVID-19 pandemic.

[1] These tables present the number of singles (S) and doubles (D) titles won by each player and each nation during the season.

The players/nations are sorted by: 1) total number of titles (a doubles title won by two players representing the same nation counts as only one win for the nation); 2) a singles > doubles hierarchy; 3) alphabetical order (by family names for players).

To avoid confusion and double counting, these tables should be updated only after an event is completed.