The 19-year-old keeper has returned to his homeland after three years with the League One club.
Cotman, who signed for Wolves in 2010 from Triglav Krani after spending time on trial, is looking forward to a new chapter in his career.
He told Maribor's official website: "Although I trained with the senior team at Wolves, we were unable to agree about a new contract.
"So I left Wolverhampton and now I will play for Maribor.
"When the best club in your country calls you, you don't think much about it.
"I'm really happy to be here."