The 39-year-old veteran defender is a free agent after spending five years at French club Lille, where he made 196 appearances in all competitions.
During his time in France, Fonte helped Lille win the Ligue 1 title in 2021 - their first top-flight championship in a decade.
He is now looking for his next club, and could be heading back to England to link up with the Saints, who he played for between 2010-2017.
Fonte was instrumental in his first spell with the south coast outfit, where he helped Southampton achieve back-to-back promotions to secure their return to the Premier League.
The centre-back chipped in with 15 goals in 288 games, with his impressive form seeing him become a regular Portugal international - culminating in Fonte winning Euro 2016.
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But he could now be heading back to relegated Southampton six years after leaving, with Russell Martin desperate to add experience to his youthful team.
talkSPORT's chief football correspondent Alex Crook gave the lowdown on the potential transfer on the White and Jordan show.
He said: "He's been a brilliant professional when you look at his career.
"He's 39 now Jose Fonte, but he's still fit as a fiddle, he's just left Lille on a free transfer.
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"And my understanding is that he would be open to returning to Southampton and try and get them back in the Premier League.
"I think that might be quite a shrewd piece of business because it is a very young Southampton team."
Fonte's last English team was in fact West Ham, who he joined from Southampton in January 2017.
However he failed to impress at the London Stadium, with the player sold to Chinese outfit Dalian Yifang for £5million a year later.
His time in the Far East lasted just a few months before he was back in Europe, with Fonte managing to recapture his form while at Lille.