The Chelsea skipper had denied the charge but an FA independent regulatory commission ruled on Thursday that he was guilty of misconduct during the Barclays Premier League defeat at QPR on October 23 last year. He was also fined ?220,000, reported to be just over a week's wages.
Terry, 31, should be available for Chelsea on Saturday though because his ban is suspended until after the appeals process has been concluded.
The defender has 14 days from the receipt of the written reasons for the decision, and if he does appeal then that hearing may not take place until the end of next month.
That could see the Chelsea captain still being available for the club's other Barclays Premier League matches in October against Norwich, Tottenham and Manchester United.
Meanwhile, questions have been asked why the ban imposed was only half the length of Liverpool's Luis Suarez, who served an eight-match suspension for racially abusing Manchester United's Patrice Evra.
The written reasons will provide the explanation for the difference in length of ban compared to Suarez and the most likely outcome is that Terry only said the insult once, while Suarez was judged by his panel to have called Evra "negro" up to seven times. Suarez was also fined around a week's wages - in his case ?40,000.
Senior figures in football's anti-racism movements have privately queried where there should be a difference, but are unlikely to speak publicly until the appeals process is completed.
Joey Barton has also criticised the decision as "a shambles" compared to his own 12-game ban for violent conduct. The midfielder, now with Marseille, said on Twitter: "What an absolute farce. 12 games for violent conduct and only 4 for that. FA should be embarrassed #shambles."
However, Jose Mourinho, Stamford Bridge manager between 2004 and 2007, told CNN: "He's not a racist - that's 100 per cent. We had a squad where we had 12 African players in the squad. It was a fantastic squad and he always had a great relationship with every one of them."
Source: PA
Source: PA