The centre-back was shown a red card for his challenge on Bournemouth’s Evanilson on 20 March, forcing him to miss Monday’s fixture against Leeds United.
An independent Regulatory Commission has subsequently charged Maguire for acting in an improper manner and/or using abusive and/or insulting words and/or behaviour towards the fourth official.
The defender has admitted the charge. The commission has imposed an additional one-match suspension and a fine.