The 30-year-old keeper, who joined from West Bromwich Albion in July of 2022, has played his way into the England squad in recent months.
He said: “I’m really happy to sign a new contract at Palace. I feel at home here, and I love playing for this club and in front of our fans.
“I’m looking forward to helping push the club forward and hopefully finishing higher up the table, playing as many games as possible for Palace in the years to come.”
Chairman Steve Parish said: “Since winning a place in Palace’s starting XI with his efforts in training and taking his chance when it came, Sam’s performances have been consistently excellent, and he has established himself as one of the top goalkeepers both in the Premier League and on the international stage. It’s fantastic that he will remain at Palace for an extended period.”
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