Uniform Commercial Code: Primary focus on Article 3 (Negotiable Instruments) and Article 9 (Secured Transactions). Essential for establishing the note's negotiability and security interests.

State-Specific Laws: Individual state regulations including usury laws, statute of limitations, recording requirements, and state-specific promissory note regulations.

Truth in Lending Act: Federal law requiring disclosure of credit terms and standardizing the manner in which costs associated with borrowing are calculated and disclosed.

CFPB Regulations: Consumer Financial Protection Bureau regulations governing consumer financial products and services, including certain types of loans and notes.

Fair Debt Collection Practices Act: Federal law governing debt collection practices, which may become relevant if the note needs to be collected through third-party collectors.

Securities Act of 1933: Federal law that may apply if the promissory note could be classified as a security, requiring registration or exemption.

State Blue Sky Laws: State-level securities regulations that may apply to the issuance of promissory notes if they qualify as securities.

Internal Revenue Code: Federal tax provisions regarding the treatment of interest income and potential tax implications of the note.

Bankruptcy Code: Federal laws affecting the enforceability of the note in bankruptcy and establishing priority rules for creditors.

Contract Law Principles: Basic contract law requirements including consideration, capacity to contract, and clear statement of contingencies that affect the note's validity.