2017–present: Transition to television and rising popularity
At the end of 2016, Jeon Mi-do reprised her role as Claire in the premiere performance of the musical Maybe Happy Ending, which was selected for the Seeya Stage. Produced by the Daemyung Cultural Factory, the musical premiered at Lifeway Hall in DCF Daemyung Cultural Factory's second building from December 20, 2016, to March 5, 2017, running for 51 performances. The premiere was directed by Kim Dong-yeon, who had also directed the tryout performance the previous September. An encore performance was held at the same venue from October 23 to November 12, 2017, and it sold out all seats before opening, continuing the popularity of the premiere. For her performance as Claire, Jeon received critical acclaim, winning two popularity awards: the Women Popularity Award at the 2017 Yegreen Musical Awards and the Best Musical Actress Award at the 2017 Stage Talk Audience's Choice Awards. She also won the Best Actress Award at the 2018 Korea Musical Awards.
In November 2017, Jeon was cast in tvN 2018 series Mother portraying Ra-ra, the former lover of Lee Seol-ak (Son Seok-ku). She officially made her television debut when the show aired from January 24 to March 15, 2018. Despite her limited screen time, she left a strong impression.
In March 2018, Jeon reprised her role as Lara Antipova in the musical Doctor Zhivago, sharing the role with Jo Jeong-eun and performing alternately at the Charlotte Theater until May 7. In the second quarter of 2018, Jeon played Mona Juul in J. T. Rogers' play Oslo, a diplomat involved in the peace agreement between Palestine and Israel. The performance took place at the Myeongdong Arts Theater from October 12 to November 4. She won the 2018 Stage Talk Audience's Choice Awards (SACA) for Best Theater Actor, further solidifying her reputation as a respected performer.
From September 2018, Jeon participated in the internal reading of the musical Paris Bakery, a new work by author Kim Han-sol and composer Kim Ki-yeon. A tryout performance was held four times at Wooran 2 from January 12 to 14, 2019. In December 2018, Jeon took part in a reading session for the musical Il Tenore, reuniting with Hue Park and Will Aronson. Set in 1930 Gyeongseong, it follows the stories of three individuals with forbidden dreams in a restrictive society.
The following year, Jeon made her big-screen debut in the fantasy film Metamorphosis. She landed her first lead role in Lee Woo-jung's drama Hospital Playlist, directed by Shin Won-ho. During the audition, she initially thought she was trying out for a patient role, but the director considered her for the lead role of Chae Song-hwa, an associate professor of neurosurgery. Shin stated that he felt she was destined for the role and noted that her casting was influenced by recommendations from Jo Jung-suk and Yoo Yeon-seok. The first season aired on tvN from March 12 to May 28, 2020.
Jeon received multiple awards for her performance in Hospital Playlist, including the Best Acting Award at the 2020 Asia Artist Awards and the Newcomer Actress Award at the 2020 Asia Contents Awards. She was also nominated for Best New Actress at the 56th Baeksang Arts Awards. In 2021, she won the Best New Actress award at the APAN Star Awards and was nominated for the Popular Star Award (Actress) at the same awards. For the drama's soundtrack, she sang a cover of Shin Hyo-beom's song "I Knew I Love" (사랑하게 될 줄 알았어), which peaked at number one on the Gaon Digital Chart.
In 2020, Jeon reprised her role as Claire in the encore of Maybe Happy Ending, joined by actresses Kang Hye-in and Han Jae-ah. She also reprised her role as Chae Song-hwa and began filming for season 2 of Hospital Playlist in late January 2021, which aired from June 17 to September 16, 2021.
In April 2021, it was reported that Jeon was in talks to appear in JTBC's TV series Thirty-Nine, a remake of the Chinese drama Nothing But Thirty, focusing on the lives and friendships of three friends nearing the age of forty. Jeon confirmed her participation in August, portraying Jeong Chan-young, a 39-year-old drama coach. The series premiered on JTBC on February 16, 2022.
Jeon decided to reprise her role as Mrs. Lovett in the 2022 encore of the musical Sweeney Todd after initially hesitating due to scheduling conflicts. With the postponement of overlapping schedules, she was able to focus fully on the production. Kim Ji-hyun, a close friend, also played a significant role in her decision. Both Jeon and Kim Ji-hyun were part of a triple cast in 2022, along with a new actress, Rina.
In December 2023, Jeon and Ji Sung were confirmed to star in the series Connection, marking her first lead role in a terrestrial channel drama since her acting debut in 2006. Jeon portrayed Oh Yun-jin, a social affairs reporter known for her assertiveness. Connection was premiered on SBS TV during the first half of 2024. On December 21, Jeon won the Best Acting Award in the Miniseries Genre/Action category at the 2024 SBS Drama Awards for her work in Connection.
On March 30, 2024, Jeon was invited to the Busan Sea Festival by the Lotte Giants for a special first pitch event.On July 16, she was appointed as one of the nine ambassadors for the 2024 Dream Theater Company. In August, Jeon appeared alongside her Hospital Playlist co-stars in a Netflix show titled A-List to Playlist, featuring Jo Jung-seok. On October 4 and 5, she participated as a narrator for the 10th anniversary memorial documentary of Shin Hae-chul titled Our Brother, Shin Hae-chul. On October 22, she appeared in the music video for the title track "그래도 돼" from Cho Yong-pil's 20th album, 20. On December 29, she appeared in Season 3 of KBS1's documentary Love Across the Sea, visiting a poverty-stricken region in Africa.
From January 17 to March 16, 2025, Jeon reprised her role as Charlotte for the 25th anniversary edition of the musical Werther. On March 24, she was announced to join the cast of the film The King's Warden. The film marked her first starring role in a commercial film. On April 10, her agency, Medialab Siso, announced that they had signed an exclusive contract with her. On May 11, 2025, Jeon made a cameo appearance in Resident Playbook, reprising her role as Chae Song-hwa from Hospital Playlist.
In October 2025, Jeon returned to the role of Claire in the 10th anniversary production of the musical Maybe Happy Ending, marking her first appearance in the role in about five years. Her scheduled performances ran until November 23, while the production itself continued at Doosan Art Center's Yonkang Hall until January 2026. The 10th anniversary production later held a national tour from February to June 2026, visiting 16 cities and selling out all 78 tour performances; Jeon was among the actors who appeared as Claire during the season.
On March 6, 2026, following its February 4 release, The King's Warden surpassed 10 million admissions on its 31st day, with Korean media describing Jeon as a "10-million actor". The film later exceeded 16.8 million admissions, making it the second most-viewed film in South Korean box-office history and the highest-grossing film released in South Korea at the time. Although media noted her relatively limited screen time and dialogue in the film, Jeon's performance earned her a nomination for Best Supporting Actress at the 62nd Baeksang Arts Awards, and received double nominations for both Best Actress and Best New Actress at the 24th Director's Cut Awards. She also sang "Friend" (Korean: 벗), a soundtrack single for the film.
In June 2026, Willa released the audiobook Pilsa, Eoreuni Doeneun Sigan (Korean: 필사, 어른이 되는 시간), narrated by Jeon as part of a talent donation project with the Jinsun Foundation for visually impaired readers. In August, she is scheduled to return to the stage in Man Theater's production of Anton Chekhov's The Seagull, reprising the role of Nina from August 9 to 31. The production marks her first play since Oslo in 2018 and her return to the role of Nina after 15 years.
