| Doubles | |
|---|---|
| 2018 Mallorca Open | |
| Champions |  Andreja Klepač  María José Martínez Sánchez |
| Runners-up |  Lucie Šafářová Barbora Štefková |
| Final score | 6–1, 3–6, [10–3] |
Latisha Chan and Martina Hingis were the defending champions, but Chan chose to compete in Birmingham and Hingis retired from professional tennis at the end of 2017.
Andreja Klepač and María José Martínez Sánchez won the title, defeating Lucie Šafářová and Barbora Štefková in the final, 6–1, 3–6, [10–3].
Andreja Klepač / María José Martínez Sánchez (champions)
Nadiia Kichenok / 
Anastasia Rodionova (quarterfinals) Monique Adamczak / Renata Voráčová (first round)
Oksana Kalashnikova / 
Makoto Ninomiya (first round)| First round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||
| 1 | A Klepač MJ Martínez Sánchez | 6 | 6 | ||||||||||||||||||||||||
| PR | A Medina Garrigues A Parra Santonja | 4 | 2 | 1 | A Klepač MJ Martínez Sánchez | 6 | 6 | ||||||||||||||||||||
 A Rosolska  A Spears | 7 | 5 | [12] | A Rosolska A Spears | 3 | 1 | |||||||||||||||||||||
J Moore  G Olmos | 5 | 7 | [10] | 1 | A Klepač MJ Martínez Sánchez | 6 | 6 | ||||||||||||||||||||
| 4 | O Kalashnikova M Ninomiya | 4 | 2 |  X Knoll  A Smith | 4 | 4 | |||||||||||||||||||||
| X Knoll A Smith | 6 | 6 | X Knoll A Smith | 6 | 6 | ||||||||||||||||||||||
| WC |  S Cîrstea  A Petkovic | 6 | 6 | WC | S Cîrstea A Petkovic | 4 | 4 | ||||||||||||||||||||
 D Jurak  C Lister | 1 | 4 | 1 | A Klepač MJ Martínez Sánchez | 6 | 3 | [10] | ||||||||||||||||||||
| K Christian S Santamaria | 6 | 6 | WC | L Šafářová B Štefková | 1 | 6 | [3] | ||||||||||||||||||||
 V Azarenka  S Kuznetsova | 2 | 3 | K Christian S Santamaria | 4 | 3 | ||||||||||||||||||||||
| WC | L Šafářová B Štefková | 6 | 6 | WC | L Šafářová B Štefková | 6 | 6 | ||||||||||||||||||||
| 3 | M Adamczak R Voráčová | 3 | 3 | WC | L Šafářová B Štefková | 6 | 6 | ||||||||||||||||||||
| V Kudermetova A Sabalenka | 4 | 6 | [2] |  L Kerkhove L Marozava | 0 | 4 | |||||||||||||||||||||
| L Kerkhove L Marozava | 6 | 3 | [10] | L Kerkhove L Marozava | 65 | 7 | [10] | ||||||||||||||||||||
D Collins  S-w Hsieh | 7 | 3 | [6] | 2 | N Kichenok An Rodionova | 77 | 5 | [5] | |||||||||||||||||||
| 2 | N Kichenok An Rodionova | 5 | 6 | [10] | |||||||||||||||||||||||
Raquel Atawo and Abigail Spears were the defending champions, but lost in the second round to Gabriela Dabrowski and María José Martínez Sánchez.
Chan Hao-ching and Chan Yung-jan won the title, defeating Sara Errani and Carla Suárez Navarro in the final, 6–3, 6–3.
Bethanie Mattek-Sands and Coco Vandeweghe were the defending champions, but chose not to participate together. Mattek-Sands played alongside Lucie Šafářová, but lost in the semifinals to Chan Yung-jan and Martina Hingis. Vandeweghe teamed up with Shelby Rogers, but lost in the first round to Andreja Klepač and María José Martínez Sánchez.
Bethanie Mattek-Sands and Lucie Šafářová were the defending champions, but lost in the second round to Andreja Klepač and María José Martínez Sánchez.
Caroline Garcia and Kristina Mladenovic were the defending champions, but Garcia chose not to participate this year. Mladenovic played alongside Svetlana Kuznetsova, but lost in the third round to Bethanie Mattek-Sands and Lucie Šafářová.
Gabriela Dabrowski and María José Martínez Sánchez were the defending champions, but Dabrowski chose to compete in Birmingham instead. Martínez Sánchez played alongside Andreja Klepač, but lost in the quarterfinals to Jelena Janković and Anastasija Sevastova.
Bethanie Mattek-Sands and Lucie Šafářová were the defending champions, but Mattek-Sands was unable to compete due to injury. Šafářová played alongside Barbora Strýcová, but lost in the semifinals to Lucie Hradecká and Kateřina Siniaková.
Sania Mirza and Barbora Strýcová were the defending champions, but chose not to participate this year.
Ekaterina Makarova and Elena Vesnina were the defending champions, but lost in the semifinals to Kiki Bertens and Johanna Larsson.
Jamie Murray and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017. Alexander Peya and Nicole Melichar won the title, defeating Murray and Victoria Azarenka in the final, 7–6(7–1), 6–3.
Ashleigh Barty and CoCo Vandeweghe defeated Tímea Babos and Kristina Mladenovic in the final, 3–6, 7–6(7–2), 7–6(8–6) to win the women's doubles tennis title at the 2018 US Open.
Bethanie Mattek-Sands and Sania Mirza were the defending champions, but both players could not participate this year due to injuries.
Abigail Spears and Katarina Srebotnik were the defending champions, but chose not to compete together. Spears played alongside Alicja Rosolska, but lost in the first round to Mihaela Buzărnescu and Alizé Cornet. Srebotnik teamed up with Shuko Aoyama, but lost in the first round to Anastasia Pavlyuchenkova and Olga Savchuk.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017. Chan played alongside her sister Chan Hao-ching, but lost in the second round to Hsieh Su-wei and Barbora Strýcová.
Bethanie Mattek-Sands and Lucie Šafářová were the defending champions, but Šafářová did not participate due to illness. Mattek-Sands played alongside Andrea Sestini Hlaváčková, but lost in the quarterfinals to Alla Kudryavtseva and Katarina Srebotnik.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017. Chan played alongside Bethanie Mattek-Sands, but lost in the quarterfinals to Andrea Sestini Hlaváčková and Barbora Strýcová.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017. Chan played alongside Bethanie Mattek-Sands, but lost in the first round to Svetlana Kuznetsova and Karolína Plíšková.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017. Chan played alongside Peng Shuai, but they lost in the first round to Irina-Camelia Begu and Mihaela Buzărnescu.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017 and Chan chose to prepare for the Asian Games instead.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017 and Chan could not participate due to a medical condition.
Latisha Chan and Martina Hingis were the defending champions, but Hingis retired from professional tennis at the end of 2017 and Chan could not participate due to a medical condition.