Employment Act (Chapter 91): Primary legislation covering basic terms and conditions of employment in Singapore. After 2019 amendments, it covers all employees except domestic workers and seafarers. Contains key provisions regarding salary payments and adjustments.

Employment Claims Act 2016: Provides the legal framework for handling salary-related disputes and claims. Essential for ensuring proper documentation of salary changes and protecting both employer and employee rights.

Central Provident Fund (CPF) Act: Governs mandatory social security savings system. Relevant as salary increments affect CPF contribution rates and amounts. Specifies employer's obligations regarding CPF adjustments.

Income Tax Act: Tax legislation that needs to be considered as salary increases impact tax obligations. Requires proper documentation for accurate tax reporting and compliance.

Personal Data Protection Act 2012 (PDPA): Regulates the collection, use, and disclosure of personal data. Relevant for handling employee's personal information in increment letters and ensuring proper consent and notification.

MOM Guidelines: Ministry of Manpower's guidelines providing best practices for employment contracts and changes, including specific documentation requirements for salary adjustments.