"I'm so sorry to disappoint the folks who have purchased tickets to my shows, but I have decided to take the rest of the year off from touring to focus on my health," the 92-year-old singer wrote on social media on Friday.
Valli, the frontman and only original member still performing with the Four Seasons, launched an extended farewell tour billed The Last Encores in October 2023.
Shows scheduled for April 2026, were rescheduled to dates in the US summer and autumn. Now, all eight performances remaining for 2026 in cities from Scottsdale, Arizona, to Detroit have been cancelled.
The Four Seasons found fame in the 1960s, but the band's hits - from Sherry to December 1963 (Oh What a Night) - span decades.
The Four Seasons sold 100 million records worldwide and were inducted into the Rock and Roll Hall of Fame in 1990.
Valli, who also established a successful solo career, received a Grammy Lifetime Achievement Award in 2026.
Known for keeping a rigorous touring schedule even as he has aged, Valli appeared to leave the door open for future performances.
"I'm looking forward to getting healthy and seeing you all again soon," Valli concluded.
