The Dutchman, who has been linked with the job currently occupied by compatriot Guus Hiddink, was quizzed on the rumors following a 1-0 win over Manchester United at Old Trafford.
Koeman had stated Friday that he would consider a move to a bigger club and hopes Hiddink "puts a good word in" for him at the English champions.
But the former Barcelona star says his words have been misinterpreted, and did not mince his words denying he was considering leaving Southampton for Stamford Bridge.
"That's the problem when you do an interview in Dutch. It's all bulls***. You can't win when you talk to them," he fired to reporters in the news conference. "I continue at Southampton and I still have one year on my contract."
While Koeman acknowledged his next move was still up in the air, he insisted there was no truth to the Chelsea speculation.
"After that, who knows. I didn't say anything about Chelsea, I got asked about Chelsea and about Hiddink so I answered," he said. "It's all bulls***."
Koeman has been in charge at St. Mary's Stadium since 2014, overseeing a seventh-place finish for Southampton last season.
Victory over Louis Van Gaal's men lifted the Saints up to eighth in the Premier League, nine points shy of Tottenham in the final Champions League qualification spot.