[14] In June 2017, Paolini won her first 100k title at Marseille where she defeated Taylor Townsend, Sara Cakarevic, Anhelina Kalinina, Dalma Gálfi, and top seed Tatjana Maria.

[15] She made her WTA Tour singles debut in the following month at the Swedish Open but lost in the first round to fifth seed Carla Suárez Navarro.

[22][23] The following month, as a lucky loser at the Prague Open, she upset third seed Daria Kasatkina[24] and defeated Anna Karolína Schmiedlová to reach her first WTA quarterfinal.

[28] She then reached the quarterfinals of the Palermo Ladies Open, defeating Laura Siegemund and Irina-Camelia Begu[29][30] before losing to top seed Kiki Bertens.

[38] At the French Open, which was postponed to September due to the COVID-19 pandemic, Paolini recorded her first major win by defeating Aliona Bolsova in the first round.

[39][40] She also recorded her first doubles win at a major, partnering Varvara Gracheva and defeating Lyudmyla and Nadiia Kichenok in the first round.

[42] She reached her first WTA 125 final at Saint-Malo by defeating Elsa Jacquemot, Nina Stojanović, Anna Karolína Schmiedlová, and Varvara Gracheva, before ultimately losing to Viktorija Golubic.

[45] The following month, she won her first WTA Tour doubles title at the Hamburg European Open, partnering Jil Teichmann.

[47] In doubles, she and partner Sara Errani, who had entered as alternates, reached the second round by upsetting the eighth-seeded team of Nicole Melichar and Alison Riske.

[50] The following month, she reached her first WTA 1000 third round, after qualifying for the Indian Wells Open and defeating Mai Hontama and 14th seed Elise Mertens.

[54] At the Melbourne Summer Set 1, Paolini and partner Sara Errani reached the doubles final, but lost to the second-seeded team of Asia Muhammad and Jessica Pegula.

[57][58] Attempting to defend her title in Portorož, Paolini defeated Tara Würth and Kaja Juvan, before losing to eventual champion Kateřina Siniaková in the quarterfinals.

[62] Paolini's 2023 season started out slow, with first-round exits at the Australian Open, Dubai, Indian Wells, Miami, and Madrid.

She won her second WTA 125 title in May, seeded fourth at the Firenze Ladies Open,[63] and reached the final of the Makarska International Championships the following month.

[67] Paolini qualified for the Cincinnati Open, where she reached the quarterfinals with wins over Marta Kostyuk and Cristina Bucșa,[68] and an early retirement by Elena Rybakina.

[82] Playing with Sara Errani, she won the doubles title at the Linz Open in February, defeating top seeds Nicole Melichar-Martinez and Ellen Perez in the final.

[85] In the final, she defeated qualifier Anna Kalinskaya to win her first WTA 1000 title, avenging her Australian Open loss earlier in the season.

13 after a quarterfinal appearance at the Porsche Grand Prix in Stuttgart, where she defeated compatriot Sara Errani and seventh seed Ons Jabeur before losing to eventual champion Elena Rybakina.

[104] Having never won a match at the tournament, Paolini, seeded seventh, reached the final at Wimbledon, recording wins over Sara Sorribes Tormo,[105] Greet Minnen,[106] Bianca Andreescu,[107] Madison Keys,[108] Emma Navarro,[109][110] and Donna Vekić.

[125] At the next WTA 1000, the Wuhan Open, on her debut, she reached the singles quarterfinals with wins over Yuan Yue[126] and lucky loser Erika Andreeva.

[3] Aged 28, Paolini became the second oldest player, after Li Na, to make their debut at the WTA Finals in November, defeating Elena Rybakina in straight sets in her opening round-robin match.

[132] At the Billie Jean King Cup finals in Spain, Paolini defeated Moyuka Uchijima and then teamed with Sara Errani to overcome Shuko Aoyama and Eri Hozumi as Italy won their quarterfinal tie against Japan.

[143] Paolini and Sara Errani won their third WTA 1000 doubles title together at the Qatar Open, defeating Jiang Xinyu and Wu Fang-hsien in the final.

[144] The following week her defense of her Dubai Tennis Championship title ended in the third round with a defeat to Sofia Kenin during which she suffered an ankle injury that forced her to withdraw from the doubles competition at the tournament.