Eilish took home Record of the Year for her song "Everything I Wanted." The singer was joined onstage by her brother, Finneas, and mentioned how she thought Megan Thee Stallion should have won instead.
"I was going to write a speech about how you deserve this, but then I was like, 'There's no way they're going to choose me,'" Eilish said.
"Black Parade" by Beyoncé, "Colors" by Black Pumas, "Rockstar" by DaBaby featuring Roddy Ricch, "Say So" by Doja Cat, "Don't Start Now" by Dua Lipa, "Circles" by Post Malone and "Savage" by Megan Thee Stallion featuring Beyoncé were also nominated for Record of the Year.
Chilombo by Jhené Aiko, Black Pumas by Black Pumas, Everyday Life by Coldplay, Djesse Vol. 3 by Jacob Collier, Women In Music Pt. III by Haim, Future Nostalgia by Dua Lipa and Hollywood's Bleeding by Post Malone were also nominated for Album of the Year.
Beyoncé made history at the awards show after winning Best R&B Performance for "Black Parade" and Best Rap Song for appearing on Megan Thee Stallion's "Savage."
Beyoncé now has more Grammy wins than any artist ever with 28.
"As an artist I believe it's my job and all our jobs to reflect the times, and it's been such a difficult time. So I wanted to uplift and encourage all of the Black queens and kings," Beyoncé said onstage while accepting the award for Best R&B Performance.
Beyoncé, earlier in the night, joined Megan Thee Stallion onstage as the rapper accepted the award for Best Rap Song.
Megan Thee Stallion said she grew up wanting to be the rap version of Beyoncé, while the singer thanked Megan Thee Stallion for allowing her to be on "Savage."
Ricch was the last artist to take the stage for the night and performed "Heartless" and "The Box."
South Korean boy band BTS were present to perform their song "Dynamite." The group danced on a red carpet and ended the concert on the rooftop of a skyscraper.
This marked BTS' first performance at the Grammys.
Doja Cat gave a sci-fi performance of her song "Say So" and Lil Baby gave viewers a cinematic performance of his song "The Bigger Picture," which took place on the street.
The performance started with a Black man being arrested and then later shot by police before Lil Baby started the song. Lil Baby then rapped as protests took place around him. Killer Mike also made a special appearance.
Malone performed "Hollywood's Bleeding" from his album of the same name, and Lipa won Best Pop Vocal Album for Future Nostalgia.
Megan Thee Stallion also performed her hit song "Savage" on a golden stage and was joined by tap-dancers. Cardi B then arrived onto the scene rocking short hair for her newest song, "Up."
The duo joined forces to perform an edited version of "WAP." Cardi B danced on a stripper pole that was connected to a giant shoe atop a giant bed.
"Black Parade" by Beyoncé, "The Box" by Ricch, "Cardigan" by Swift, "Circles" by Malone, "Don't Start Now" by Lipa, "Everything I Wanted" by Billie Eillish and "If The World Was Ending" by JP Saxe featuring Julia Michaels were also nominated for Song of the Year.
Guyton performed "Black Like Me" and was followed by Lambert performing "Bluebird" and Morris performing "The Bones."
The Grammys additionally paid tribute to those in the music industry who have died over the past year.
Lionel Richie paid tribute to Kenny Rogers by performing "Lady" and Brandi Carlile paid tribute to John Prine by performing "I Remember Everything." Brittany Howard performed "You Will Never Walk Alone."
Swift gave a fairy-tale like performance of "Cardigan," "August" and "Willow."
She was joined onstage by her collaborators Aaron Dessner and Jack Antonoff. Swift started the performance by laying on the roof of a cottage before she joined Dessner and Antonoff.
The stage was made to look like a magical forest and fit the aesthetic of her two most recent albums, Folklore and Evermore.
Silk Sonic, consisting of Mars and .Paak, made their first appearance at the Grammys with an old-school performance of their song "Leave the Door Open."
Mars and .Paak wore matching orange suits and were surrounded by sparkling lights. The concert paid homage to performances from the 1970s.
"I can't wait to dance to that at every wedding for the rest of my life," Noah said about "Leave the Door Open." Lambert then won Best Country Album for Wildcard.
Lipa performed both "Don't Start Now" and "Levitating" featuring DaBaby. Lipa's set featured an image of a full moon in the background and the singer donned a sparkling pink ensemble.
Lipa and DaBaby's careers were explored in special video packages that were released for each Record of the Year nominee throughout the night.
The rapper performed his song "Rockstar" featuring Ricch after his video, and Black Pumas performed "Colors" after their video.
Styles kicked off the 63rd annual Grammy Awards. He was the first artist to perform after opening remarks from Noah.
The singer was joined by a band inside of a circular room. Black Pumas, Haim, Billie Eilish and Finneas were also hanging out inside the room.
Styles performed "Watermelon Sugar" and watched as the others performed when it was their turn. Eilish stood on top of a car to sing "Everything I Wanted" before Haim performed "The Steps."
The Grammys announced a number of winners earlier on Sunday. Lady Gaga and Ariana Grande won Best Pop Duo/Group Performance, .Paak won Best Melodic Rap Performance for "Lockdown" and Bad Bunny won Best Latin Pop or Urban Album for YHLQMDLG.
The ceremony paid tribute to independent venues that have been impacted by the COVID-19 pandemic. This included having bartenders, box office managers and others who work at the Troubadour and Hotel Café in Los Angeles, the Apollo Theater in New York City and the Station Inn in Nashville, presenting awards.