Well wonder no more.
Mario jumping off a tower of pipes towards the goal.

Following the news that Charles Martinet, the voice of Mario since 1991, was "stepping back" from the iconic role, it was unclear whether or not Martinet's last time as Mario would be in the upcoming Switch title, Super Mario Bros. Wonder. Thankfully, we were able to find a definitive answer to that thanks to a statement issued to IGN.

According to Nintendo's statement to IGN, Charles Martinet will not be the voice of Mario in Super Mario Bros. Wonder. Though confirming that Martinet will not be the voice of Mario in the game, the game company stopped short of revealing just who the new voice of Mario is.

"While Charles is not involved in Super Mario Bros. Wonder, we're excited to honor his legacy and contributions, including looking ahead to what he'll be doing as a Mario Ambassador," a Nintendo spokesperson said in a statement to IGN. "Character voice actors will be credited in the game credits, so please wait for the game to be released."​
This means that Martinet's last time voice Mario in a game came in the 2022 Nintendo Switch title, Mario + Rabbids Sparks of Hope.

Super Mario Bros. Wonder is an upcoming 2D side-scrolling Mario title. Mario will be able to take a "Wonder Flower" that can alter his world and reality, like turning him into an elephant.