Overview
Maryland (MD) local taxes are included in the SIT calculation per state requirements effective January 1, 2005. If you obtain a copy of the Circular E for the state, you can see where this is explained in more detail: "The MD state taxes are determined by county lived in. The filing statuses for MD are Married, Single or Head of household."
For Maryland, this may be handled by using the resident locality for the employee on the Master, having the local taxes calculated separately, then having all the information filed together. See http://business.marylandtaxes.com/taxinfo/withholding/default.asp.
For anyone that should be paying MD local tax, the employee's primary mailing address needs to be for MD and a resident locality ("Res Tax Locality") for the appropriate county tax needs to be selected on the employee Master record. The local tax is then included in the SIT calculation.