Singapore e-Invoicing Guide

Singapore has taken a pragmatic, incentive-driven approach to e-invoicing through its InvoiceNow initiative, built on the Peppol network. Rather than imposing a sweeping B2B mandate, Singapore has focused on making adoption attractive — starting with government procurement and using GST registration requirements to gradually expand coverage.

The InvoiceNow framework uses the PINT SG specification on the Peppol network, with IMDA overseeing the technical infrastructure and IRAS handling the tax compliance aspects. Businesses are identified by their Unique Entity Number (UEN), which serves as the Peppol routing identifier.

Singapore's timeline is incremental. B2G registration became mandatory for government suppliers from April 2025. New voluntary GST registrants must adopt InvoiceNow from November 2025, followed by all voluntary GST registrants from April 2026. This measured approach allows the ecosystem to scale gradually while maintaining quality.

Government suppliers must register on the Peppol network and be capable of receiving e-invoices through InvoiceNow. For B2B, the requirements are expanding through GST registration: new voluntary GST registrants from November 2025 and all voluntary GST registrants from April 2026 must adopt InvoiceNow.

Existing B2B businesses face no mandatory e-invoicing obligation — adoption remains voluntary but is strongly encouraged through IMDA grants and government incentives. B2C transactions are entirely outside the framework. The PINT SG specification requires UEN and postal addresses as mandatory fields in compliant invoices.

Singapore uses a post-audit model via the Peppol network. Businesses connect through Peppol Access Points and exchange invoices using the PINT SG specification. There is no government clearance or pre-authorization — invoices flow directly between trading partners, and IRAS receives data for audit purposes.

The 5-corner model means businesses interact with the network through their Access Point provider, which handles the technical aspects of sending, receiving, and validating invoices. IMDA provides grants to help SMEs cover the costs of adoption, making the transition financially accessible.

Singapore's penalty framework is focused on government procurement. Non-compliant suppliers risk exclusion from government tenders and may face difficulties maintaining procurement relationships. Since B2B is largely voluntary, there are no broad B2B-specific penalties — the incentive model relies on grants and procurement advantages rather than fines.