Contracts (Rights of Third Parties) Act 1999: Primary legislation governing how third parties can enforce terms of a contract. Essential for third party payment agreements as it determines enforcement rights and obligations of the third party.

Law of Property Act 1925: Fundamental legislation relevant for any security arrangements or property-related aspects within the payment agreement.

Bills of Exchange Act 1882: Legislation governing negotiable instruments and relevant if the payment agreement involves bills of exchange or similar payment instruments.

Payment Services Regulations 2017: Implements EU Payment Services Directive (PSD2). Regulates payment services and payment service providers, setting out key requirements for payment arrangements.

Money Laundering Regulations 2017: Sets out anti-money laundering requirements and Know Your Customer (KYC) obligations that may need to be addressed in the agreement.

Financial Services and Markets Act 2000: Regulatory framework for financial services in the UK, relevant if the agreement involves regulated financial activities.

Doctrine of Consideration: Common law principle requiring that all parties provide something of value in the contract. Essential for ensuring the agreement is legally binding.

Privity of Contract: Common law principle concerning the relationship between parties to a contract and their rights to enforce it.

Agency Principles: Common law principles governing relationships where one party acts on behalf of another, relevant for third party payment structures.

Consumer Credit Act 1974: Relevant if the payment agreement involves consumer credit arrangements or consumer transactions.

Consumer Rights Act 2015: Applicable if the agreement involves consumers, setting out consumer protection requirements.

GDPR and Data Protection Act 2018: Data protection legislation that must be considered for aspects of the agreement involving personal data processing and storage.