2018 Miami Open
The 2018 Miami Open presented by Itaú (also known as 2018 Miami Masters) was a professional men and women's tennis tournament played on outdoor hard courts. It was the 34th edition of the Miami Open, and part of the Masters 1000 category on the 2018 ATP World Tour, and of the Premier Mandatory category on the 2018 WTA Tour. All men and women's events took place at the Tennis Center at Crandon Park in Key Biscayne, Florida, United States, from March 19 through April 1, 2018. It was the last time the tournament was played at the Tennis Center at Crandon Park. The tournament moved to the Hard Rock Stadium starting in 2019.
Finals
Men's singles
John Isner defeated 
Alexander Zverev, 6–7(4–7), 6–4, 6–4
Women's singles
- Sloane Stephens defeated
Jeļena Ostapenko, 7–6(7–5), 6–1
Men's doubles
- Bob Bryan / Mike Bryan defeated
Karen Khachanov / Andrey Rublev, 4–6, 7–6(7–5), [10–4]
Women's doubles
Ashleigh Barty / CoCo Vandeweghe defeated 
Barbora Krejčíková / Kateřina Siniaková, 6–2, 6–1
Points and prize money
Point distribution
- Players with byes receive first round points.
Prize money
ATP singles main-draw entrants
Seeds
The following are the seeded players. Rankings and seedings are based on ATP rankings as of March 19, 2018.
† The player did not qualify for the tournament in 2017. Accordingly, points for his 18th best result are deducted instead.
‡ The player used an exemption to skip the tournament in 2017. Accordingly, points for his 18th best result are deducted instead.
Withdrawals
The following players would have been seeded, but they withdrew from the event.
† Ramos Viñolas is entitled to use an exemption to skip the tournament and substitute his 18th best result (45 points) in its stead. Accordingly, his points after the tournament will remain unchanged.
Other entrants
The following players received wildcards into the singles main draw:
The following players received entry using a protected ranking:
The following players received entry from the qualifying draw:
Ričardas Berankis
Yuki Bhambri
Liam Broady- Alex de Minaur
Rogério Dutra Silva- Bjorn Fratangelo
Calvin Hemery
Darian King- Thanasi Kokkinakis
- John Millman
- Michael Mmoh
- Cameron Norrie
The following player received entry as lucky loser:
Withdrawals
- Before the tournament
- Julien Benneteau → replaced by
Ivo Karlović 
Pablo Cuevas → replaced by Frances Tiafoe
Federico Delbonis → replaced by 
Mirza Bašić
Alexandr Dolgopolov → replaced by 
Radu Albot- Philipp Kohlschreiber → replaced by
Lukáš Lacko 
Paolo Lorenzi → replaced by Jérémy Chardy- Florian Mayer → replaced by
Vasek Pospisil - Gaël Monfils → replaced by
Nicolás Jarry - Andy Murray (hip surgery) → replaced by Thomas Fabbiano
Rafael Nadal (psoas muscle injury) → replaced by Maximilian Marterer- Lucas Pouille → replaced by
Víctor Estrella Burgos - Albert Ramos Viñolas → replaced by Mikhail Youzhny
- Andreas Seppi → replaced by Nicolás Kicker
Dominic Thiem (ankle injury) → replaced by 
Marius Copil- Jo-Wilfried Tsonga → replaced by
Dušan Lajović 
Stan Wawrinka → replaced by Taylor Fritz
Retirements
ATP doubles main-draw entrants
Seeds
- 1 Rankings as of March 19, 2018.
Other entrants
The following pairs received wildcards into the doubles main draw:
WTA singles main-draw entrants
Seeds
The following are the seeded players. Seedings are based on WTA rankings as of March 5, 2018. Rankings and points before are as of March 19, 2018.
† The player did not qualify for the tournament in 2017. Accordingly, points for her 16th best result are deducted instead.
Other entrants
The following players received wildcards into the singles main draw:
- Amanda Anisimova
Victoria Azarenka- Claire Liu
- Bethanie Mattek-Sands
- Whitney Osuigwe
- Bernarda Pera
- Ajla Tomljanović
- Serena Williams
The following players received entry from the qualifying draw:
- Katie Boulter
- Danielle Collins
- Viktorija Golubic
Polona Hercog- Sofia Kenin
- Monica Niculescu
Rebecca Peterson- Andrea Petkovic
- Alison Riske
- Natalia Vikhlyantseva
- Stefanie Vögele
Wang Yafan
The following player received entry as a lucky loser:
Withdrawals
- Before the tournament
- Belinda Bencic → replaced by Océane Dodin
- Dominika Cibulková → replaced by Lara Arruabarrena
- Margarita Gasparyan → replaced by Madison Brengle
- Kateryna Kozlova → replaced by
Verónica Cepede Royg - Ana Konjuh → replaced by Kateryna Bondarenko
- Mirjana Lučić-Baroni → replaced by
Yulia Putintseva - Peng Shuai → replaced by
Alison Van Uytvanck - Lucie Šafářová → replaced by Johanna Larsson
- Maria Sharapova → replaced by Jennifer Brady
- Laura Siegemund → replaced by Kristýna Plíšková
During the tournament
Retirements
WTA doubles main-draw entrants
Seeds
- 1 Rankings as of March 5, 2018.
Other entrants
The following pairs received wildcards into the doubles main draw:
The following pair received entry as alternates:
Withdrawals
- Before the tournament