I.O.I: Loop (; stylized in all caps) is the third extended play (EP) by South Korean girl group I.O.I. Produced by Swing Entertainment and distributed by Stone Music Entertainment and KT Genie Music, the EP was released on May 19, 2026. The EP marked the group's reunion to celebrate their tenth debut anniversary.

Formed as a temporary project group from the television program Produce 101 (2016), I.O.I found success but only actively promoted for less than a year before disbanding in January 2017 as part of their contract. While the members pursued solo or group careers in their respective agencies, attempted reunions never materialized until it was announced in December 2025 that nine of the eleven members would reunite to release new music for their tenth anniversary.

The EP features a total of six tracks, carried by its singles "Goodbye with a Smile" and "Suddenly". The physical version of I.O.I: Loop features one version, including a photo book, a CD, two random photo cards, a poster, a special printed photo, a mini accordion booklet and a photo taken with a Polaroid camera. I.O.I will promote the EP through their Loop Tour around Asia.

Background On July 1, 2019, Studio Blu confirmed that the group would return in October 2019 with nine members, excluding Yoo Yeon-jung and Jeon So-mi. On September 6, the planned comeback was postponed to December. On October 29, the comeback was canceled due to scheduling conflicts between the members and the Mnet vote manipulation investigation.

On December 25, 2025, the members revealed that I.O.I would reunite for a comeback in May 2026; with the exception of Zhou Jieqiong and Kang Mi-na—who were unable to participate due to commitments to acting—the remaining nine members joined forces for this reunion project. On February 23, 2026, Swing Entertainment announced that the group will reunite for a new album release in May, without Mina and Jieqiong. Swing also confirmed that they will manage the group's promotional activities for the album and their 10th anniversary. On March 9, 2026, I.O.I launched official social media accounts to mark their 10th anniversary.

Release and promotion On April 20, the group announced that their album would be titled I.O.I: Loop and scheduled its release for May 19. The following day, the album's promotional schedule was unveiled. On April 22, a concept film was released. On April 23, the first set of concept photos was revealed. Four days later, the EP's tracklist was released. On April 28, the second set of concept photos was unveiled. On May 4, the pre-release single "Goodbye With A Smile" was released. The single, recorded in 2016 and produced by Jung Jinyoung, features Mina and Jieqiong who were unable to join the comeback activities. The following day, the first music video teaser for the title track, "Suddenly" (), was released.

Track listing

Charts + Chart performance for I.O.I: Loop Chart (2026) Peakposition Japanese Download Albums (Billboard Japan) 70 South Korean Albums (Circle) 33

Release history + Release history for I.O.I: Loop Region Date Format Label South Korea May 19, 2026 CD Various

References