The German 33-year-old was charged over the summer for bringing the game into disrepute after his club were caught spying on Middlesbrough, and later found to have also spied on both Oxford City and Ipswich Town.
Following a hearing, the FA have handed him a fine and a suspended sentence, which will allow Eckert to manage the side against fierce rivals Portsmouth on Sunday and for the rest of the season.
The suspension will run through until the end of the 2027/28 season.
The club itself was handed no further punishment by the FA.
In a statement, the Saints' owner, Dragan Solak said: “I’m pleased that the independent panel has come to a decision and that we have an outcome. We have already suffered enough, and we appreciate the panel’s recognition of that.
“We are confident the manager has learned from this matter, and a suspended sentence allows him to continue in his role. I firmly believe that Tonda is one of Europe’s most exciting young coaches, and with this distraction removed, I am confident he can lead the team to a successful season. I’d like to thank our fans for standing by us and showing the team so much support during a time when we have needed them more than ever."
Southampton started the season on -4 following sanctions handed down by the English Football League, and currently sit 13th in the standings after eight games with 10 points.
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