Md. Code, Real Property § 9–302

(a) Except for work done or materials furnished under a contract enumerated in § 9–305 of this subtitle, a contractor or subcontractor who does work or furnishes material under a contract shall be entitled to prompt payment under subsection (b) of this section.

(b) (1) If the contract is with an owner, the owner shall:

(i) If the contract does not provide for specific dates or times of payment, pay to the contractor undisputed amounts owed under the terms of the written contract, within the earlier of:

1. 30 days after the day on which the occupancy permit is granted; or

2. 30 days after the day on which the owner or the owner’s agent takes possession; or

(ii) If the contract provides for specific dates or times of payment, pay to the contractor undisputed amounts owed within 7 days after the date or time specified in the contract.

(2) Paragraph (1) of this subsection does not apply to any contract between the contractor and:

(i) The State;

(ii) A county;

(iii) A municipal corporation;

(iv) A board of education; or

(v) A public authority or instrumentality.

(3) If the contract is not with an owner, the contractor or subcontractor shall pay undisputed amounts owed to its subcontractors within 7 days after receipt by the contractor or subcontractor of each payment received for its subcontractors’ work or materials.