[4] On 16 July 2017, Wickmayer married long-time boyfriend and former professional football player Jérôme van der Zijl.

In the 2008 Fed Cup tie versus Ukraine, Wickmayer sprang a surprise victory over reigning Australian Open women's doubles champion Kateryna Bondarenko.

On 1 October 2009, it was announced that Wickmayer and fellow Belgian tennis professional Xavier Malisse were to defend themselves before the Flemish anti-doping tribunal for failing to properly fill out their whereabouts.

Wickmayer replied in a press release that the failure to follow procedure was due to her not being able to log on to the relevant website, not being able to contact the right people when needed, and not being in the country when written admonitions arrived by mail from the Flemish anti-doping authorities.

Seeded third, she reached the final defeating Julia Görges, Raluca Olaru, wildcard Kimiko Date-Krumm, and Shahar Pe'er.

Seeded 12th, Wickmayer reached the quarterfinals after wins over qualifier Elena Baltacha, wildcard Petra Martić, and Timea Bacsinszky.

At the Porsche Tennis Grand Prix held in Stuttgart, Wickmayer moved to the second round, before falling for the second consecutive time to fellow Belgian Justine Henin, 3–6, 5–7.

Beating Alla Kudryavtseva, Julia Görges, and Patty Schnyder, she reached the fourth round where she lost to 31st seed Kaia Kanepi.

Seeded second, she reached the final once again defeating Dinara Safina, qualifier Sabine Lisicki, Simona Halep, and Peng Shuai.

Seeded seventh at the Open GdF Suez, Wickmayer made it to the quarterfinals by beating Elena Vesnina and Klára Zakopalová.

[66] Representing Belgium in the Fed Cup tie versus Serbia, Wickmayer won both of her rubbers over Bojana Jovanovski and Aleksandra Krunić.

[71] Wickmayer then went on to play in Doha at the Qatar Open where she reached the quarterfinals defeating Ayumi Morita, seventh seed Francesca Schiavone, and Ksenia Pervak.

[87] Wickmayer then beat Heather Watson in her second-round match,[88] and in the quarterfinals upset second seed and last year finalist Marion Bartoli.

[104] At the Qatar Open, she retired due to a low back injury during her first-round match versus 15th seed Roberta Vinci.

Seeded second at the Nanjing Open, she reached the semifinals defeating Yaroslava Shvedova, wildcard Wang Yafan, and Anna-Lena Friedsam.

As the second seed, she reached the final after beating qualifier Chan Chin-wei, Olga Govortsova, Zheng Saisai, and Luksika Kumkhum.

[132] At the Qatar Ladies Open, Wickmayer reached the quarterfinals, beating Andrea Petkovic, eighth seed Caroline Wozniacki, and Jana Čepelová.

[165] Competing in Poland at the Katowice Open, she lost in the first round to top seed and home crowd favorite Agnieszka Radwańska.

[166] Wickmayer began clay-court season at the Prague Open with wins over eighth seed Camila Giorgi, Aleksandra Krunić, and qualifier Danka Kovinić.

[174] Wickmayer started her US Open Series at the Rogers Cup where she advanced to the main draw with wins over Donna Vekić and eighth seed Julia Görges.

[175] Seeded fourth at the Vancouver Open, Wickmayer reached the semifinals with wins over Canadian wildcard Gabriela Dabrowski, qualifier Julia Glushko, and Nao Hibino.

As the top seed, Wickmayer reached the final defeating Julia Boserup, Kristie Ahn, CiCi Bellis, and Maria Sakkari.

[219] The week after the tournament in Budapest, Wickmayer played at the Abierto Mexicano Telcel, where she was defeated in the first round by wildcard Daniela Hantuchová.

[223] Competing at the Rabat Grand Prix, her first clay-court season tournament of the year, Wickmayer was defeated in the first round by Ekaterina Makarova.

[239] After the Australian Open, Wickmayer competed at the first edition of the Newport Beach Challenger in California where she was defeated in the first round by seventh seed Ajla Tomljanović.

[244] Seeded sixth at the Zhengzhou Open, Wickmayer reached the semifinals after wins over Vera Zvonareva, wildcard Wang Xiyu, and qualifier Mai Minokoshi.

[247] Seeded fourth at the Surbiton Trophy, her first grass-court tournament of the year, Wickmayer beat both Bojana Jovanovski Petrović and qualifier Victoria Duval to reach the quarterfinals where Harriet Dart defeated her.

[255] Seeded sixth at the Dow Tennis Classic, Wickmayer beat both Lu Jiajing and qualifier Ann Li to reach the quarterfinals.

[256] As the top seed at the GB Pro-Series Shrewsbury, Wickmayer reached the final after wins over Lesley Kerkhove, qualifier Jessika Ponchet, British wildcard and defending champion Maia Lumsden, and Harmony Tan.

She won the doubles title partnering with Kristina Mladenovic at the Korea Open defeating top seeds Asia Muhammad and Sabrina Santamaria from the United States.