Goods and Services Tax Act (Cap. 117A): Primary legislation governing GST requirements, tax invoice requirements, and GST registration obligations for businesses in Singapore
Income Tax Act (Cap. 134): Legislation governing income tax implications of invoicing, including requirements for record-keeping and income reporting
Electronic Transactions Act (Cap. 88): Regulates electronic transactions and digital signatures, relevant for e-invoicing validity and enforceability
Contract Law Act: Fundamental legislation governing contract formation, validity, and enforcement in Singapore
Companies Act (Cap. 50): Requirements for maintaining proper business records and accounting documentation, including invoicing records
Currency Act: Regulations regarding currency requirements for invoicing in Singapore
Peppol E-Invoicing Network Requirements: Technical and operational standards for e-invoicing through the Peppol network in Singapore
InvoiceNow Framework: Singapore's national e-invoicing framework based on the Peppol standard
Personal Data Protection Act 2012 (PDPA): Regulations governing the collection, use, and disclosure of personal data in business transactions including invoicing
Limitation Act (Cap. 163): Establishes time limits for enforcement of payment claims and legal actions related to invoices
IRAS Record Keeping Requirements: mandatory requirements for maintaining invoice records for a minimum period of 5 years
