Singapore GST Invoicing Guidance for Customers

• A tax invoice (or customer accounting tax invoice) is the key support document for input tax claims, and invoice/receipt records must be kept for at least 5 years.
• GST-registered businesses must transmit invoice data to IRAS using InvoiceNow-Ready Solutions, with mandatory participation to be rolled out in phases.
• Tax invoices must be issued to GST-registered customers for standard-rated supplies within 30 days of time of supply; they are not required for non-GST-registered customers, zero-rated, exempt, or deemed supplies.
• Tax invoices must clearly show all required information on one document, including the GST registration number; missing/incomplete details may prevent the customer from claiming input tax.
• For multiple standard-rated items, GST may be calculated either item-by-item or on the subtotal, with possible rounding differences.

Source: iras.gov.sg

Note that this post was (partially) written with the help of AI. It is always useful to review the original source material, and where needed to obtain (local) advice from a specialist.

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