U2‘s bassist Adam Clayton turns 64 today (happy birthday!).

Even the social media account of the band has celebrated this. They posted a video of fans donning fake mustaches in honor of Clayton's 2024 Sphere look.

He is definitely one of the most underrated bassists of all time. His subtlety is sometimes hard to appreciate, I know it was for me when I first began listening to U2.

But he also has some on-the-nose classic riffs that are iconic. “New Year's Day” wouldn't be the song it is without Clayton.

Adam Clayton's 10 best U2 bass lines

U2 members Adam Clayton, Bono, and The Edge with Las Vegas Sphere background.

So, in honor of his 64th birthday, we ranked the 10 best bass lines from Clayton.

Honorable Mentions: “Gloria” (October); “Dirty Day” (Zooropa); “Vertigo” (How to Dismantle an Atomic Bomb); “Get on Your Boots” (No Line on the Horizon)

“Atomic City” (Single)

Call it recency bias, but Clayton's latest work is some of his best. “Atomic City” is if “Call Me” and “London Calling” had a U2 baby. Clayton's performances of the song at the Sphere are even better. As Bono says, he makes “the Sphere disappear.”

The bass part in particular is reminiscent of Green Day's “Holiday.”

“I Still Haven't Found What I'm Looking For” (The Joshua Tree) 

Sometimes, simple is better. Clayton's reggae-like bass part is simple, but moving. Arguably, on the studio version, you hear more of Clayton's bass part than The Edge's similarly subtle guitar riff. This won't be the last time a Joshua Tree song makes the list, and that's because Clayton came to his full form in this album.

“God, Pt. II” (Rattle and Hum)

Rattle and Hum was another step in Clayton's evolution. “God, Pt. II” laid the groundwork for Achtung Baby. From jump, Clayton's bass hits you like a ton of bricks.

It's almost like an intenser version of Clayton's “I Still Haven't Found What I'm Looking For” bass line.

“Magnificent” (No Line on the Horizon) 

One of the highlights of No Line on the Horizon is “Magnificent.” It begins with The Edge's grungy guitar riff. As he repeats the sliding riff, the rest of the band comes in. Clayton's bass line here is akin to the Achtung Baby era — it's as groovy as something like “Mysterious Ways.”

“Mysterious Ways” (Achtung Baby) 

Speaking of, “Mysterious Ways” is one of Clayton's finest hours. The song itself is groovy, but Clayton found the perfect driving force for the song. It's no wonder why the band composed the song around the bass line part.

Live performances of the song also do Clayton's part justice.

“The Crystal Ballroom” (Songs of Innocence Bonus Track)

Most of U2's recent work isn't really bass-centric. It's rare these days for Clayton to get to drive a song. “The Crystal Ballroom,” a bonus track from their 2014 album Songs of Innocence, is a great modern example of what he can do.

Think The Munsters theme with a little bit of “Magnificent” in there and you have Clayton's “Crystal Ballroom” bass line.

“Bullet the Blue Sky” (The Joshua Tree)

There is something haunting about “Bullet the Blue Sky.” From Bono's growls to The Edge's scathing guitar and Larry Mullen Jr.'s perfect drum beat. Beneath all of it is a simple, but thumping bass line from Clayton. It doesn't change at all throughout the song, proving Clayton to be the one constant in the song.

“The Fly” (Achtung Baby)

The Sphere was a marvel for several reasons. Its sound was the cherry on top of the high-tech screen that blasted images in 16K resolution.

That's why it's hard to fully appreciate U2's performances of “The Fly” during the residency. Much is made of the code-breaking visuals as the venue manipulates depth perception. Seeing the sky crash down is amazing, no doubt, but Clayton's bass playing on “The Fly” only gets better with age.

The Achtung Baby album version is incredible, but the Sphere emphasized Clayton's playing in a way that will make you see him in a whole new light. While the residency ended, videos and bootlegs can be heard which can give you somewhat of an idea. But it truly was something you had to witness in person.

“Bad” (The Unforgettable Fire) 

Maybe it sounds a bit disjointed, but “Bad,” the studio version, is still a treasure. Adam Clayton doesn't come in until after the first verse, sliding his way into the picture. The bass part goes off on its own tangents in the studio version, but if Paul McCartney can do it on songs like “I Want You (She's So Heavy),” why can't Clayton?

“New Year's Day” (War) 

Well, this was obvious, wasn't it? Adam Clayton's magnum opus is “New Year's Day.” It's a song that is completely driven by him.

In the '80s and '90s, U2 played fantastic renditions of the song. From Bono's impassioned screams to The Edge's haunting guitar riff, Clayton still stole the show. That's largely because the tone he uses on his bass for live performances is even better than the album. It's fuzzier and has more force than whatever he used in the studio.