"Swim" (stylized in all caps) is a song by South Korean boy band BTS. It was released on March 20, 2026, as the lead single of the group's sixth Korean-language studio album Arirang.
On January 4, 2026, Big Hit Music announced BTS's comeback after a four-year hiatus during which they completed their mandatory military service and released solo work. The title of the album, Arirang, was revealed on January 15, referencing the Korean folk song of the same name. On March 3, BTS revealed the album's track listing and production credits, with the seventh track "Swim" highlighted in black, indicating the song is the lead single from the album.
Before the release of the album, Hybe's official YouTube channel released two teasers for the song and its music video.
"Swim" has been described as alternative pop and synth-pop. The lyrics are entirely English. BTS member RM, who is the main songwriter of "Swim", said: "I wrote the lyrics and I tried to express the confusion that we all had before [and] after the military... and we want to just keep swimming." RM said the track has a "clean and smooth allure", and has compared it to Pyongyang naengmyeon.
In a statement, BTS wrote: <blockquote>"[It's] a song that mirrors life itself. [We] hope it resonates with many people as they move through each day, taking each moment as it comes, splashing along and continuing to swim forward. The more you listen, the warmer it feels, so [we] hope it becomes a source of strength as people go through their lives. Also, just like the folk song 'Arirang,' which has been passed from mouth to mouth and stayed with people through generations, [we] hope 'Swim' will remain close to people's hearts for a long time to come."</blockquote>
"Swim" was released as the lead single from Arirang on March 20, 2026. On March 23, BTS released the instrumental version. On March 27, the remix album for "Swim", titled Keep Swimming, was released. The nine-track album includes the original and instrumental versions of "Swim", as well as seven remixes reflecting each member's musical taste.
In the United States, "Swim" was also sold by Target as a four-inch "tiny vinyl" with the song "Normal" as the b-side. For its television debut, BTS performed "Swim" at the Guggenheim Museum for The Tonight Show Starring Jimmy Fallon.
The music video for "Swim" was released on YouTube on March 20, 2026. Directed by Tanu Muiño and featuring actress Lili Reinhart alongside BTS, it was filmed against the ocean backdrop of Lisbon and sees the group working on a sailing ship. The music video surpassed 5 million views within an hour, while trending at #1 in 70 countries.
"Swim" debuted at number one on the Billboard Hot 100, marking BTS's sixth song to debut at the top, and their seventh song to top the chart, the most No. 1s on the chart among groups in nearly half a century. It debuted with 15.3 million streams, 25.8 million in airplay audience, and 154,000 sales, and also debuted at number 2 on the Streaming Songs, number 18 on the Radio Songs, and number 1 on the Digital Song Sales chart, making it the group's highest entries on the former two, while becoming its 13th number one on the sales chart.
"Swim" was streamed over 14 million times on Spotify on its first day of release, surpassing 100 million streams on the platform in eight days, being the fastest song of the year to do so. "Swim" also reached number 1 on the Top 100 chart on Melon an hour after its release, overtaking "Bang Bang" by Ive. The song also debuted at number 2 on the Official Singles Charts in the UK, marking the group's fifth top-10 hit and highest-ever position on the chart.
"Swim" also earned BTS their first number-one song in Germany. They also became the first group in German chart history to simultaneously hold the number one position on both the German album and singles charts with two new entries, "Swim" and Arirang. In Brazil, "Swim" debuted at number one on the Brasil Hot 100, becoming the first foreign song to top the chart since the relaunch of Billboard Brasil in August 2023.
Credits adapted from Apple Music.