The bassist, who was one of the founding members of the American rock group along with Weir, Kreutzmann, Jerry Garcia and Ron “Pigpen” McKernan, died at the age of 84 surrounded by his family on Friday.
The group became known for its fusion of genres including rock, jazz and folk, which contributed to the counterculture generation of the 1960s.
“Phil Lesh was my brother. Not by blood, but still family,” Kreutzmann wrote on Instagram next to a photo of the couple from their youth.
“I’ve heard so many of you tell me that the Grateful Dead changed your life. Yeah, well… Phil Lesh changed mine.
“Phil turned me into John Coltrane. In the early days of our friendship, he wasn’t just like a brother to me—he was like an older brother. Roommate. A group mate. Teacher.”
He continued by reflecting on how lifelong friendships and family relationships are “complex and dynamic” but “will ultimately stand the test of time.”
“So keep only the good memories because they are the only ones that matter. That’s what I’ll do. Because love is real, it doesn’t disappear,” he added.
“Thank you Phil. I’m going to miss the hell out of you.”
Weir posted a collection of photos of his onstage performances with Lesh over the years on Instagram, while also reflecting on how his late bandmate influenced him in the John Coltrane Quartet.
He revealed that Lesh introduced the band to the “wonders of modern classical music” and said their discussion around the genre helped him “grow up”.
“Concurrent with all of this was the ongoing conversation about the things (ideas) we present outside of music and the effect it will have on shaping the world around us – let’s just say Phil wasn’t particularly averse to ruffling a few feathers,” he added .
“We had our differences, of course, but it’s not trite to say that it only made our work together more meaningful.”
“Our conversation and interaction will last at least until the end of my days.”
Ward signed off his tribute by writing: “In the meantime, considering that death is the last and best reward for a *life well and fully lived*, I rejoice in his release.”
A statement posted on Lesh’s Instagram on Friday said: “Phil Lesh, bassist and founding member of The Grateful Dead, passed peacefully this morning. He was surrounded by his family and filled with love.
“Phil brought immense joy to everyone around him and leaves behind a legacy of music and love. We ask that you respect the Lesch family’s privacy at this time.
He was best known for the song Unbroken Chain, about the counterculture band’s relationship with the public.
Lesh also sang the sad Box Of Rain, which he wrote while his father was dying.
He revealed in 2006 that he had prostate cancer and that he had a liver transplant in 1998 following a hepatitis infection.
The Grateful Dead disbanded after lead singer Jerry Garcia died in 1995 in a drug rehab clinic, aged 53.
Other members who have died include Brent Midland in 1990 from a drug overdose, McKernan from liver disease in 1973 and Keith Godchaux in a car accident in 1980 after he left the band.
Lesh also toured with spin-off bands including Other Ones, The Dead and Furthur, and his own band Phil Lesh and Friends.
On Wednesday, the music foundation MusiCares announced that it will honor Lesh, along with other former members such as Kreutzmann, Mickey Hart and Weir, as the 2025 Person of the Year for their charity and campaign.
Kreutzmann said Lesh and the other members would attend the 34th annual Person of the Year benefit gala, where they planned to celebrate their 60th anniversary and pay tribute to Garcia.