Songwriting and producing O'Connell has said his experience playing characters helped with writing music for his sister
Billie Eilish, because he writes from her perspective and for her vocal range. Finneas had written and produced his song "
Ocean Eyes" originally for his band, and gave it to Eilish when her dance teacher asked them to write a song for a choreography. They posted the song on
SoundCloud, garnering praise from various websites. Finneas also co-wrote and produced Eilish's debut studio album,
When We All Fall Asleep, Where Do We Go? (2019), which debuted atop the US and UK charts. He won the 2020
Grammy Awards for
Producer of the Year, Non-Classical;
Record of the Year and
Song of the Year for Eilish's "
Bad Guy"; and
Album of the Year and
Best Engineered Album, Non-Classical for
When We All Fall Asleep, Where Do We Go?. Eilish's subsequent albums
Happier Than Ever (2021) and
Hit Me Hard and Soft (2024) were also co-written and produced by Finneas. He has also been known to work with Grammy winners the Coutinho twins (Mason and Jules Coutinho). He produced the 2019 single "
Lose You to Love Me" by
Selena Gomez, which peaked at number one on the
Billboard Hot 100, and two tracks on the 2019 album
Romance by
Camila Cabello. He also produced "
Moral of the Story" by
Ashe, and collaborated with
John Legend on an unreleased song. O'Connell composed the score for the 2021
teen drama film
The Fallout.
Solo music career He is the lead singer and songwriter of the band The Slightlys, which played the
Warped Tour in 2015. with the music video released in 2019. In 2017, he released the single "I'm in Love Without You", and eight singles in 2018: "Break My Heart Again", "Heaven", "Life Moves On", "Landmine", "Hollywood Forever", "College", "Luck Pusher", and "Let's Fall in Love for the Night". In early 2019, Finneas played his first sold-out headline shows in New York His debut EP,
Blood Harmony, was released on October 4, 2019. while the second single, "Shelter", was released on August 22, 2019, and the third single, "I Don't Miss You At All", on September 20, 2019. In October 2019, he embarked on his first headlining tour, in five cities in the US, in addition to a performance at
Austin City Limits. It peaked at number 17 on the US
Billboard Alternative Songs chart. On October 21, Finneas released his single "
Can't Wait to Be Dead" about his love-hate relationship with the Internet, along with a visual directed by Constellation Jones the following day. Finneas is one of twelve artists featured on
Ringo Starr's 2021 EP
Zoom In, contributing backing vocals to the song "Here's to the Nights". On March 2, 2021, Finneas and Ashe released a collaboration titled "
Till Forever Falls Apart", which he co-wrote and produced. On August 5, 2021, Finneas announced that his debut studio album
Optimist would be released on October 15, 2021, through
Interscope Records, and shared its lead single "A Concert Six Months from Now". He also composed the scores to the films
The Fallout (2021), and
Vengeance (2022). On August 8, 2024, he announced that his second studio album ''
For Cryin' Out Loud!'' would be released on October 4, 2024, that day he also released the title track as the lead single. in February 2025 On January 24, 2025, Finneas made his
Like a Version debut with a cover of
The Zombies' "
Time of the Season". O'Connell embarked on the United States leg of his 2025 tour in support of ''For Cryin' Out Loud!'' on February 13, with a performance in
Nashville, Tennessee.
Acting In 2011, Finneas played a student in the comedy film
Bad Teacher. He had recurring guest roles on
Modern Family and
Aquarius, and played Alistair in the
final season of the musical comedy-drama television series
Glee in 2015. In April 2026, Finneas made an appearance as a fictionalized version of himself on an episode of
Beef. == Personal life ==