The 26-year-old faced 24 civil lawsuits over sexual assault and misconduct allegations. He was not charged by two grand juries and settled 20 of 24 lawsuits in June, with a further three settlements reported ahead of a hearing verdict early this month.
Watson was initially given a six-game suspension and no further fine after a disciplinary hearing conducted by former US district judge Sue L. Robinson.
The NFL formally appealed against that ruling in order to seek further punishment, and they have now agreed an extended suspension and fine with the NFLPA.
Watson will additionally be required to commit to an evaluation with behavioural experts while also following a mandatory treatment program.
The ban means that Watson's first game back is scheduled to be on December 4, against his former team the Houston Texans.
Watson denied any wrongdoing after the accusations were made. He then last week apologised to "all of the women that I have impacted."
The Texans traded the three-time Pro Bowler to Cleveland in March, and the Browns promptly signed Watson to a five-year, $230m extension that is entirely guaranteed.