Individuals can pay their Maryland taxes with a credit card. This service applies to taxes owed for the current year or any back year (if you have a bill).The State of Maryland is EXEMPT from Maryland Tax. Tax Exempt Number is 30002563 which is located on each card. It is not wise to put personal spend on it. If you have a business structure set up such as an LLC, that gives you limited liability. Maryland Surcharge Laws. Business credit cards operate similarly to personal credit cards. You make purchases on the card and receive a statement at the end of each billing cycle. Credit card surcharging can be a complex question for law firms.