Fagerson has been punished for his red card in the narrow 25-24 defeat to Wales at Murrayfield following a disciplinary hearing on Tuesday.
The 25-year-old was dismissed in the second half on Saturday after making contact with Wyn Jones’ head when launching himself into a ruck.
An independent disciplinary committee deemed the foul play warranted a six-week suspension but reduced that by two weeks to account for mitigating factors, including the player’s admission of foul play and a good disciplinary record.
Fagerson will miss Six Nations matches against France, Ireland and Italy, along with one further game yet to be determined. He has the right to appeal.
The decision divided the sport with former Wales and Lions captain Sam Warburton unconvinced that it was worth of a sending off.
“I think that’s harsh if you’re going to give him a red card,” Warburton said during commentary on the BBC.
“Wyn Jones is a threat, he can pick that ball up legally. Because he’s tucked his elbow it doesn’t look as good. I do feel for Zander because he has to get rid of Wyn Jones.”
However, referee Nigel Owens was adamant when assessing the incident: “The red card shown to Scotland prop Zander Fagerson in the Wales game was as clear as you could see.”
Reuters contributed to this report