Billie Joe Armstrong Praises ‘Awesome’ Billie Eilish After FireAid Collab: ‘We Had the Best Time With Our Friend’

Billie Joe Armstrong can’t say enough good things about that other Billie. Following Sunday night’s 2025 Grammy Awards, the Green Day frontman told Billboard that he was still buzzing about sharing the stage with Billie Eilish at last weekend’s all-star FireAid benefit concert.

“The fact that we got to play together… she’s just, she’s a pretty awesome young lady,” Armstrong said. “And it was an honor to be able to share the stage with her.” Eilish was a surprise guest during Green Day’s opening set at FireAid, which organizers said on Tuesday has raised an estimated $100 million for relief efforts to date following the devastating wildfires that have killed 29 people to date and destroyed more than 16,000 homes and structures. Native Angelenos Eilish and brother/producer Finneas returned later in the show for an acoustic set, which included her songs “Birds of a Feather,” “Wildflower” and “The Greatest.”

Armstrong recalled that when he first started hearing about Eilish years ago he watched some footage on Instagram and was captivated by one particular piece of merch: a headband that read “Billie.”

“I said, ‘I have to have to have that!,’” he said at the time; Eilish subsequently sent him a “bunch of merch,” including one of those headbands. “I saw her play a couple times and she was fantastic. You just knew something special was going to happen with her.”

In an Instagram post over the weekend, Green Day gave more props to Eilish, writing, “It was an absolute honor to play @fireaidla last night. We had the best time with our friend @billieeilish, who joined us for ‘Last Night On Earth.’ LA, we are sending all our love to you.” The roll included backstage snaps with Eilish in a series of pics from their performance at the charity show.