2018–2020: When We All Fall Asleep, Where Do We Go?
In February 2018, Eilish embarked on her second headlining concert tour, the Where's My Mind Tour, which concluded in April 2018. "Bitches Broken Hearts" was re-released worldwide on March 30, 2018. For Record Store Day 2018, Eilish released "Party Favor" on a pink 7-inch vinyl, along with a cover of "Hotline Bling", by Drake, as the B-side. Eilish collaborated with American singer Khalid on the single "Lovely", which was released on April 19, 2018, and added to the soundtrack for the second season of 13 Reasons Why. She released "You Should See Me in a Crown" in July 2018. The same month, Eilish performed at the Mo Pop Festival.
On the day of release for her single "When the Party's Over", Eilish was featured in Vanity Fair's "73 Questions" rapid-fire questionnaire video series by Joe Sabia, who revisited an interview from October 2017. The resulting video was a side-by-side time capsule of both interviews showing her growth in popularity over one year. Eilish embarked on the 1 by 1 Tour in October 2018 to further support Don't Smile at Me; it concluded in March 2019. She signed a talent contract with Next Management for fashion and beauty endorsements in October 2018. She was placed on the 2018 Forbes 30 Under 30 list in November and released the single "Come Out and Play" in November 2018, which was written for a holiday-themed Apple Inc. commercial. In early January 2019, Don't Smile at Me reached one billion streams on Spotify, making her the youngest artist to top one billion streams on a project. That month, Eilish released "Bury a Friend" as the third single from her debut studio album, When We All Fall Asleep, Where Do We Go?, along with "When I Was Older", a single inspired by the 2018 film Roma, which appeared on the compilation album Music Inspired by the Film Roma. In February, Eilish partnered with YouTube on a documentary miniseries, "A Snippet Into Billie's Mind". "Wish You Were Gay", her fourth single from the album, was released on March 4, 2019.
When We All Fall Asleep, Where Do We Go? was released on March 29, 2019. Spotify launched a "multi-level campaign behind the album", creating a multimedia playlist and "new product features" that Spotify said "allow for vertical video content, custom assets, and editorial storylines, all with the goal of creating more meaningful and engaging context for [Eilish's] fans." In Los Angeles, Spotify set up a "pop-up enhanced album experience", which included different artwork and a "multi-sensory" experience of each track for fans. The album debuted atop the Billboard 200 as well as on the UK Albums Chart, making Eilish the first artist born in the 2000s to have a number-one album in the US and the youngest female ever to have a number-one album in the United Kingdom. Upon the album's debut, Eilish broke the record for the most simultaneously charting songs on the US Billboard Hot 100 by a female artist, with 14, after every song from the album, excluding "Goodbye", charted on the Hot 100. The fifth single from the album, "Bad Guy", was released in conjunction with the album. A remix of the song featuring Justin Bieber was released in July 2019. In August, "Bad Guy" peaked at number one in the US, ending Lil Nas X's record-breaking 19 weeks at number one with "Old Town Road". She is the first artist born in the 2000s and the youngest artist since Lorde (with "Royals") to have a number-one single.
Eilish began her When We All Fall Asleep Tour at Coachella Festival in April 2019, with the tour concluding on November 17, 2019, in Mexico City. In August 2019, she partnered with Apple Music for Music Lab: Remix Billie Eilish, part of the Apple Store's Music Lab sessions during which fans deconstruct her song "You Should See Me In A Crown" and learn how to create their own remix on Apple devices and GarageBand. On September 27, 2019, Eilish announced her Where Do We Go? World Tour. The tour began in Miami on March 9, 2020, and ran for two more shows on March 10 in Orlando and March 12 in Raleigh before Eilish ended the tour prematurely due to the COVID-19 pandemic. The tour was set to conclude in Jakarta on September 7.
On November 7, 2019, Jack White's Third Man Records announced that the label would release an acoustic live album of Eilish's performance from the record label's Blue Room, exclusively sold on vinyl at Third Man retail locations in Nashville and Detroit. On November 13, 2019, she released her next single, "Everything I Wanted". On November 20, 2019, Eilish was nominated for six Grammy Awards, including Record of the Year and Song of the Year for "Bad Guy" as well as Album of the Year and Best New Artist. At age 17, she became the youngest artist to be nominated in all four General Field categories. In the same month, Eilish was crowned 2019's Billboard Woman of the Year.
On January 14, 2020, Eilish was announced as the performer of the title track for No Time to Die, the 25th installment in the James Bond film franchise, written and produced with her brother. With this announcement, Eilish became the youngest artist to write and perform a James Bond theme song. It became the second Bond theme song to top the British official charts and the first Bond theme performed by a female artist to do so. It was also Eilish's first number-one single in the UK. At the 62nd Annual Grammy Awards, she became the youngest person to win the four main Grammy categories – Best New Artist, Record of the Year, Song of the Year, and Album of the Year – in the same year. During the COVID-19 pandemic, Eilish and her brother performed for both iHeart Media's Living Room Concert for America and Global Citizen's Together at Home concert series, singing a cover of Bobby Hebb's "Sunny" for the latter. Both virtual concerts were an effort to raise awareness and funds towards fighting the disease. On April 10, 2020, "Ilomilo" was sent to Italian contemporary hit radio stations by Universal Music Group, as When We All Fall Asleep, Where Do We Go?'s seventh and final single. On July 30, 2020, Eilish released "My Future", her first original release since "No Time to Die", along with an animated video. In 2020, she became the youngest person to feature on the Forbes Celebrity 100 list, with earnings of $53 million. In September 2020, Eilish released a collection of branded ukuleles with guitar manufacturer Fender.
On October 7, 2020, Eilish announced a virtual concert titled Where Do We Go? The Livestream. Staged in Los Angeles on October 24, the performance utilised extended reality (XR) technology and featured drummer Andrew Marshall and Eilish's brother, Finneas. Ticket proceeds were used to support touring crew members affected by COVID-19 cancellations via Crew Nation. In a Vanity Fair interview, Eilish said she was working on "sixteen new songs and lov[ing] them all", revealing an upcoming musical project. Eilish won three Billboard Music Awards on October 24—Top Female Artist, Top Billboard 200 Album (When We All Fall Asleep, Where Do We Go?), and Top New Artist—out of the 12 that she was nominated for. Also that month, she announced a new single, "Therefore I Am", which was released along with its video on November 12, 2020. Eilish performed "Therefore I Am" and "My Future" at the Jingle Ball in December 2020.
