Moyes, 54, made the remark, for which he apologised, to BBC reporter Vicki Sparks following Sunderland’s 0-0 draw with Burnley in the Premier League on March 18.
The FA said Moyes’ remarks were “improper and/or threatening and/or brought the game into disrepute”.
Moyes was unhappy with one of Sparks’ questions and said to her: “You were just getting a wee bit naughty at the end there, so just watch yourself. You still might get a slap even though you’re a woman. Careful the next time you come in.”
Although the interview was over at the time Moyes made his remark, the camera was still running and footage of the incident was published three weeks later by a national newspaper.
Moyes was contrite about the incident when questioned at a subsequent press conference.
“In the heat of the moment, I made a mistake in my comments to a BBC reporter, which I profoundly regret. I was disappointed with myself for it,” said Moyes, who resigned as Sunderland boss following their relegation from the Premier League.
“I subsequently phoned the reporter and apologised, which she accepted. It’s not my character, it’s not my type, as most people know and once again I apologise for it.”
The club described Moyes’ conduct as “wholly unacceptable” but stood by him as he attempted – in vain – to preserve Sunderland’s status among the English footballing elite.
Moyes denied the charge but the FA’s independent regulatory commission upheld it.
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