The middle forward had already been contracted through 2027 and could become one of the joint venture's most-capped players by the end of his new deal.
Twal will be 33 when the contract expires and would be the second-most capped Wests Tigers player with 261 appearances if he played every game of the next four seasons.
Fellow Lebanese international Robbie Farah (277) is the club's games record holder since Balmain and Western Suburbs merged in 2000.
Twal now holds the longest active contract at the Tigers alongside fellow middle Sione Fainu, whose new deal was announced on Wednesday.
He has been a senior leader in the forward pack in the club's fight to bounce back from three consecutive last-placed finishes between 2022 and 2024.
"This is a club that means so much to me and my family, it's where I made my debut and has given me the opportunity to play footy at the highest level," Twal said.
"I'm really looking forward to what's ahead for this group."
A Parramatta junior, Twal made his NRL debut at the Tigers in 2017 and served as stand-in captain for the first time in 2025.
Twal had notoriously been the NRL's most-capped active player to have never scored a try until crossing against Melbourne in his 116th game in 2023.
He now has two four-pointers across 165 first-grade appearances.