The Greek defender joined Liverpool from Olympiakos in 2020 and has registered 12 assists in 63 appearances for the Merseyside club.
"I feel very glad to be here to extend my contract," Tsimikas said in a club statement. "I feel like all the sacrifices I did and other things, the work I put in, [that] everything pays off.
"But this keeps me fully motivated for the rest. As I've said in many, many interviews, this team has many, many things to achieve all together and I wanted to be from the first minute a part of it.
"I think this team has very big potential to win more trophies and we will go for it. Everybody, I think, is 100% there [and] focused for the next games and everybody is ready to achieve big things in the future."