[2] At the US Open, after qualifying, she defeated fellow Romanian Sorana Cîrstea in the first round, in three sets, for her first main-draw major match-win.

[3][note 1] At the Australian Open, Bogdan reached the main draw through qualifying, but was defeated in straight sets in the first round by Elena Vesnina.

[3][note 1] At the US Open, Bogdan reached the second round of the main draw, matching her result from 2016, but was defeated in three sets by Monica Niculescu.

[3][note 1] Bogdan reached her first WTA Tour final at the Poland Open but lost to fifth seed Caroline Garcia.

[8] Seeded sixth at the Emilia-Romagna Open in Parma, Bogdan reached the semifinals where she was defeated by eventual champion Mayar Sherif.

[3][note 1] At Wimbledon, she reached the third round for the first time at this major but lost to Lesia Tsurenko in a tight three-set match with a 38 points tiebreak in the third, the longest in women's singles Grand Slam history.

[10] Bogdan successfully defended the title at the WTA 125 event in Iași, defeating compatriot Irina-Camelia Begu in the final.

[3][note 1] In February, Bogdan headed to Europe, and still on hardcourts, participated in her home tournament, the Transylvania Open where she got to the final but lost to Karolína Plíšková, in straight sets.

In the first round, Bogdan upset 2nd seed Leylah Fernandez,[15] then beat Greet Minnen, who had made it into the main draw as a lucky loser.

[18] In October, Bogdan qualified for the Japan Open and reached the quarterfinals with wins over Veronika Kudermetova[19] and fourth seed Marie Bouzková,[20][21] before losing in the last eight to eventual champion Suzan Lamens.