Md. Code, Education § 15–102

(a) Each public institution of higher education may honor credit cards as payment for:

(1) Tuition and fees;

(2) Room and board; and

(3) Any goods or services purchased from other auxiliary enterprises.

(b) The governing boards of the institutions shall determine which credit cards are acceptable for this purpose. However, a public institution may not accept a credit card from any credit card company which charges that institution a vendor discount, service charge or similar fee in excess of 2.5 percent.