The 33-year-old, who joined the Baggies in 2011, has made 51 appearances for the Premier League side including 31 this season, and has scored twice in their current campaign.
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|10/1||West Brom are 10/1 with Bet365 to beat Newcastle 2-0 at the Hawthorns|
"The dressing room and the lads here are fantastic and it's great to be a part of it," McAuley told the club's official website.
"You play for them and you don't want to let them down. You try your best for them every week and that's a thing throughout the group. Everyone is trying their best for each other.
"The best way to describe it is like playing with your mates. It's the closest I've come to that feeling throughout my career, apart from when you're younger and you're playing with your friends."
West Brom stand eighth in the Premier League table with six games remaining, and face Newcastle next at home on Saturday.