Consumer Credit Act 1974: Governs consumer credit agreements, including requirements for form and content, regulation of interest rates and charges. Applies when borrower is a consumer rather than a business.

Financial Services and Markets Act 2000: Provides regulatory framework for financial instruments and requirements if the promissory note is to be traded or transferred.

Late Payment of Commercial Debts (Interest) Act 1998: Applicable for business-to-business transactions, sets statutory interest rates for late payments.

Unfair Contract Terms Act 1977: Ensures contract terms are fair and reasonable, particularly important for interest rate provisions in promissory notes.

Consumer Rights Act 2015: Applies to consumer transactions and ensures fairness of terms in consumer contracts.

Limitation Act 1980: Sets time limits for enforcing debt, including six-year limitation period for simple contracts.

Bills of Exchange Act 1882: Establishes basic principles governing promissory notes and requirements for negotiability.

Common Law Principles: Covers fundamental contract law principles including formation, consideration, capacity to contract, and enforceability.