Farrell escaped any on-pitch punishment in last Friday's match after his shoulder made contact with the jaw of Jack Clement but after he was cited for "dangerous tackling".
"Farrell accepted foul play but challenged that it met the red card threshold, however, the panel upheld the charge and Farrell received a four match ban," the RFU said in a statement.
The RFU added that the four-match ban will be reduced to a three-week ban if Farrell completes the World Rugby Coaching Intervention Programme.
The three-week ban means he will miss two European and one Premiership match for Saracens but frees him to play for England against Scotland and Italy on February 12, both at Twickenham.
In September 2020 Farrell was red carded and banned for 10 weeks, then cut to five, for a "reckless and totally unacceptable" high tackle on Wasps' Charlie Atkinson (18).
He also served a two-game ban for a high tackle in 2016, long before the current protocols on tackle height were introduced.
Farrell, who has been in brilliant form at fly half for table-topping Saracens this season, was a regular at inside centre for England under Eddie Jones, with Marcus Smith (23) preferred at 10.
Smith has not played since November due to an ankle injury but is expected to return for Harlequins this weekend.
Fellow fly half George Ford (29) is also expected to return for new club Sale later this month having not played since injuring his ankle in the Premiership final in June.
Farrell also regained the captaincy from the injured Courtney Lawes (33) for England's November series.
New England head coach Steve Borthwick will announce his Six Nations squad next Monday.
