The veteran Italy goalkeeper helped Juve to a third consecutive domestic double and the Champions League final last term.
Buffon, 39, has previously stated his intention to retire from international football after the 2018 World Cup in Russia but it now appears that tournament will be the last act of a stellar career.
"I'm 99.9 percent certain of retirement," he told Sky Sport 24.
"I'm going to have one final, intense season, rich in big moments, and then it will be time to say enough is enough."
Real Madrid inflicted Champions League final heartache on Buffon and his colleagues, and winning European football's big prize next time around is the only thing that could convince the former Parma keeper to soldier on.
"We've just left one small possibility open with the president [Juventus chief Andrea Agnelli]," Buffon added.
"That is if we manage to win the Champions League I will carry on playing one more year to try to win the Club World Cup and other trophies."
Although the Champions League has proved tantalisingly elusive, Buffon has eight Serie A titles and four Coppa Italia to his name, along with the 1998-99 UEFA Cup and 2006 World Cup.