Sanders was fined $15,000 and the organization $35,000. Sanders grabbed the back of his leg and collapsed to the ground during the fourth quarter of Pittsburgh's 24-17 win.
NFL executive vice president of football operations Ray Anderson handed out the discipline after meeting with Sanders last week.
Sanders initially played coy in public comments about the incident, but in recent weeks has said the matter was being handled internally.
Also fined on Friday by the league were Panthers safety Haruki Nakamura and Packers tight end Ryan Taylor, $21,000 each; Titans safety Michael Griffin, $20,000; Raiders cornerback Tyvon Branch, Panthers defensive end Greg Hardy, and Cardinals linebacker Quentin Groves, $15,750 each; Ravens LB Dannell Ellerbe, $10,000; Eagles quarterback Michael Vick, Colts cornerback Cassius Vaughn, and Steelers safety Will Allen, $7,875 apiece.
Anderson said it found no evidence the Steelers, on an organization-wide basis, were instructing or condoning the faking of injuries for competitive purposes.
"If I believed that to be the case, the discipline would be substantially more," Anderson said. "Instead, it reflects the commissioner's strong view that it is the responsibility of the club to insure that its players are familiar with and in compliance with the league's competitive rules."
In an open letter to Sanders and Steelers general manager Kevin Colbert, Anderson cited video evidence to the contrary of Sanders' contention that he was in severe pain while lying on the ground, before or after the play.
Sanders sat out one play -- a team trainer attended to him -- and then returned to the game for the next play, a Pittsburgh punt. Anderson noted that Sanders outran his teammates and downed the ball.
"The video of the play shows Sanders running swiftly and effortlessly toward the punted ball, and then leaving the field with no sign of discomfort," Anderson wrote. "Sanders also played the rest of the game without difficulty."
The NFL sent out a memo to team general managers and coaches in September that said, "The Competition Committee deprecates feigning injuries." The league reiterated it had the power to fine players, coaches or teams or even take away draft picks.
This is the first punishment the league has handed out for faking an injury.
When asked two days before his meeting with the league if he thought the NFL had a problem with faking, Sanders said "Not that I know of."
The NFL pointed out the idea of faking injuries has been "frequently discussed" by the league's competition committee but acknowledged the difficulties in enforcement. With player safety a hot-button issue, the NFL does not want to encourage legitimately injured players to leave the field unnecessarily.
Vick threw a low block at Saints safety Roman Harper during an interception return for a touchdown by Patrick Robinson. Allen made a late hit on Giants receiver Victor Cruz. Vaughn struck Miami RB Reggie Bush late.
After saying "I can't talk about that," last week when asked about Sanders' meeting with the league, Pittsburgh quarterback Ben Roethlisberger said, "People get hurt. That's the way it is. You can't control injuries in this league."
An injury to another Pittsburgh receiver is giving Sanders an opportunity to shine for something other than his acting skills. The team leader in receptions, Antonio Brown, has not practiced this week and almost assuredly will not play Monday night against Kansas City (1-7).
"As a third wide receiver, you've got to know multiple positions. You've got to know almost every position on the field," Sanders said. "So that's my job. If someone goes down, I've got to go in and fill that void."
A foot injury last season contributed to Sanders being limited to more of a complementary role while Mike Wallace and Brown ascended to stardom. This week, Sanders gets his turn for the Steelers (5-3).
"He's a great player; he's always been ready," Wallace said. "There's never been a doubt in my mind that if anybody goes down he can step in here and not miss a beat."