The former Kiwi international is delighted to be staying put in West Yorkshire.
“I’m really happy to have signed for another year at Cas,” he said.
“The club and fans have been amazing during my team here. I’m really looking forward to getting back to pre season and kicking off the 2016 season.”
Tigers coach Daryl Powell is pleased to have retained a player of such experience and quality.
“Jake Webster had a strong season in 2015 and we are confident he can grow further as a player,” he said.
“I’m delighted he has agreed to extend his stay here at Cas to give our backline both an experienced and a fresh edge to it.”