Defending champion Ashleigh Barty won the women's singles tennis title at the 2021 Miami Open after Bianca Andreescu retired from the final with the scoreline at 6–3, 4–0. Barty saved a match point en route to the title, in the second round against Kristína Kučová.
Barty and Naomi Osaka were in contention for the WTA No. 1 singles ranking. Barty retained the top ranking by winning the title after Osaka lost to Maria Sakkari in the quarterfinals, ending a 23-match winning streak dating to the 2020 Cincinnati Masters.
Seeds All seeds received a bye into the second round.
Draw
Finals
Top half
Section 1
Section 2
Section 3
Section 4
Bottom half
Section 5
Section 6
Section 7
Section 8
Qualifying
Seeds
Qualifiers
Lucky loser Kirsten Flipkens
Qualifying draw
First qualifier
Second qualifier
Third qualifier
Fourth qualifier
Fifth qualifier
Sixth qualifier
Seventh qualifier
Eighth qualifier
Ninth qualifier
Tenth qualifier
Eleventh qualifier
Twelfth qualifier
References
External links Main draw Qualifying draw