Maryland Code, Commercial Law § 12-907

(a) If credit under a revolving credit plan is offered and extended by a credit grantor which is a depository institution in connection with a demand deposit account or other transaction account maintained by the borrower with the credit grantor under an agreement or arrangement where the credit grantor agrees to honor checks, drafts, or other debits to the account by making extensions of credit to the borrower under a revolving credit plan, any charges customarily imposed by the credit grantor under the terms governing the account in the absence of any associated revolving credit plan may continue to be imposed on the account without specific reference or incorporation in the agreement governing the revolving credit plan.

(b) The account charges referred to in subsection (a) of this section include:

(c) The amount of any charge imposed on the account may be charged to the account under the plan as a loan and may be included in the outstanding unpaid indebtedness under the terms of the agreement governing the revolving credit plan, to the extent the balance in the demand deposit or other transaction account is insufficient to pay the charge.