Late Payment of Commercial Debts (Interest) Act 1998: Legislation governing statutory interest rates and compensation for late payment in commercial transactions. Essential for calculating any interest claims in the demand letter.

Limitation Act 1980: Sets time limits for bringing claims and ensures the debt isn't statute-barred (generally 6 years for simple contracts). Must be considered before issuing any demand letter.

Pre-Action Protocol for Debt Claims: Part of Civil Procedure Rules that outlines required steps before court proceedings, including information that must be provided to debtors and timeframes for response.

Consumer Credit Act 1974: Provides consumer protection provisions and specific requirements for consumer notices when dealing with consumer debt.

Consumer Rights Act 2015: Legislation covering fairness of terms and consumer protections that must be considered when drafting demands to consumers.

GDPR and Data Protection Act 2018: Regulations governing the handling of personal information and privacy considerations in any correspondence containing personal data.