Simmons has yet to play this season after declaring himself not mentally ready, following a drawn-out saga in which he's made it clear he no longer wants to play in Philadelphia.
The Sixers have already fined him $US2 million ($A2.7 million) in penalties for holding out of training camp and not taking part in required team activities.
According to a new report from ESPN, the NBA side has now resumed fining the Aussie to the tune of $US360,000 ($A486,000) for every game he misses.
Philadelphia stopped fining him two weeks ago when he said he would get assistance from a mental health professional.
However, while Simmons has cooperated with a team doctor for a back issue, he had not told the 76ers about his plan for mental health treatment, despite being asked to submit it more than once, according to ESPN.
The All-Star has refused to provide any details or to consult with mental health providers arranged by the team.
Simmons has four years and $147 million ($A198 million) remaining on his five-year contract.
At practice, he works individually and fines will begin again if he doesn't take part in team events, such as film study and strength training, per the report.
Simmons has been seeking a trade for months, but the 76ers have been unable to come to a satisfactory trade agreement.
The Aussie and his representatives are not happy with how the team responded to criticism of his subpar play in the Eastern Conference semi-finals last season.
In his absence, Philadelphia are off to a 7-2 start - the best record in the Eastern Conference - after a 109-98 win over the Detroit Pistons.
The renewed fines for Simmons kicked in from that game according to ESPN reports.
Just before the season opener in New Orleans, coach Doc Rivers ejected Simmons from practice after he wouldn't sub in for a drill.
He was subsequently was suspended for the first game.
Ben Simmons not mentally ready to play
Simmons told the team he wasn't mentally ready to begin the season and has been sidelined for every one of their games so far.
But instead of working with the team's staff, Simmons has reportedly been working with mental health professionals through the NBA Players Association since the summer.
He has reportedly yet to provide the team with any details from those meetings.
Simmons' camp apparently told ESPN they expect to update the team on the player's progress "once he is comfortable doing so."
Simmons recently made it clear he doesn't want to play for the Sixers again, but president of basketball operations Daryl Morey made it quite clear that he had no plans to trade him without getting comparable value back.
Players Association executive director Michele Roberts defended Simmons after he said he wasn't mentally ready.
"Is it so hard to believe that Ben’s not mentally at a place to compete?" Roberts said.
"Professional athletes - like the rest of us - have difficult periods in our lives that require time and energy to heal.
"We have and will continue to provide Ben with the support and resources he needs to work through this.
"Threatening the prospect of 'another four years' serves no one’s interests. Like Tobias [Harris], I say let’s respect Ben’s space and embrace him while allowing him the time to move forward.
"So, take a breath and count to 10: We are all too good to continue to play this perpetual game of chicken.”
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