Singapore e-invoicing: InvoiceNow and GST InvoiceNow – what global tax leaders need to know

Singapore continues to accelerate its digital tax transformation. What began as InvoiceNow — the national e-invoicing network built on the global Peppol interoperability framework — has evolved into a multiyear mandate requiring structured invoice data to be transmitted to the Inland Revenue Authority of Singapore (IRAS).

Under the GST InvoiceNow Requirement, certain GST-registered businesses must transmit invoice data to IRAS via InvoiceNow-ready solutions or accredited service providers, in addition to exchanging invoices with trading partners.

With the latest announcements extending mandatory adoption to all GST-registered businesses by 2031, multinational enterprises (MNEs) must now treat Singapore’s requirement as a strategic digital compliance programme — not a short-term local initiative.

• Singapore is moving towards continuous transaction controls (CTC). GST InvoiceNow introduces structured invoice data transmission to IRAS, signalling a shift from periodic GST reporting to near real-time tax transparency.

• Mandatory adoption expands to all GST-registered businesses by 2031. The phased rollout begins with new voluntary registrants in 2025–2026 and scales to all GST-registered entities — including large multinational enterprises — by April 2031.

• PINT-SG is the strategic invoice format for domestic compliance. Built on the global Peppol framework, PINT-SG enables interoperability while aligning invoice data with Singapore GST requirements and reporting obligations.

InvoiceNow is Singapore’s nationwide e-invoicing infrastructure built on the Peppol network, a global interoperability framework enabling secure exchange of structured electronic business documents. Key elements relevant to multinational enterprises:

• Peppol transport infrastructure enabling secure structured document exchange
• Peppol IDs, which are the routing identifiers used on the network — in Singapore, these are typically based on a company’s UEN (Unique Entity Number — Singapore’s legal entity registration number)
• Structured machine-readable XML invoice format – in PINT-SG format, replacing PDFs and exchanging invoices as email attachments
• Support for both B2B and B2G invoice exchange

For global tax and IT teams already using Peppol elsewhere, the infrastructure is familiar — but Singapore is introducing local GST and reporting alignment requirements.

PINT stands for Peppol International Invoice. It’s designed to provide a globally interoperable invoice standard while allowing structured local regulatory alignment. The PINT framework is built on three core design principles:

1. Shared (Global core)

A common invoice structure used consistently across jurisdictions, ensuring cross-border interoperability.

2. Aligned (Jurisdiction-aligned rules)

Standardised tax and validation rules tailored to domestic regulations. In Singapore, this includes GST-specific validation and classification logic.

3. Country-specific extensions

Additional fields or requirements mandated locally but implemented in a controlled way to preserve global compatibility.

PINT-SG applies the PINT model to Singapore’s GST environment. It:

• Incorporates Singapore GST data requirements
• Enforces validation aligned to IRAS expectations
• Supports structured GST breakdowns
• Uses defined GST category codes
• Enables alignment between invoice data and GST reporting obligations

While SG BIS Billing 3.0 remains supported in Singapore – especially for nonresident suppliers, Infocomm Media Development Authority (IMDA) guidance confirms that SG PINT is the required format for domestic exchange.

Singapore government agencies prefer to receive invoices via InvoiceNow – it’s now the standard for public procurement in the country. Suppliers must ensure:

• Valid CorpPass registration
• Approved vendor status on Vendors@Gov
• Routing to the correct agency Peppol ID
• Inclusion of required government-specific reference fields

Public sector invoicing may introduce enhanced referencing requirements beyond standard Peppol elements. The Invoice Response document is now available for e-invoices submitted to the Accountant-General’s Department (AGD) Peppol ID. B2G suppliers who are enabled for the Invoice Response capability can receive real-time invoice status updates through their accredited service provider.

The GST InvoiceNow Requirement introduces a 5-corner model — making Singapore the first country to implement this:

1. Supplier (and their ERP)
2. Supplier access point/accredited service provider
3. Buyer access point
4. Buyer (and their ERP)
5. IRAS (tax authority)

Unlike traditional invoice exchange on Peppol, GST InvoiceNow requires transmission of tax-relevant invoice data to IRAS for GST reporting purposes. This represents a structural shift from periodic reporting towards structured transactional transparency – the clear direction of travel is “continuous transaction controls” (CTC).

IRAS requires transmission of structured invoice data covering:

• Standard-rated supplies
• Zero-rated supplies
• Exempt supplies
• Standard-rated purchases
• Zero-rated purchases

This aligns invoice data with GST return reporting categories.

Singapore’s GST InvoiceNow rollout now spans multiple phases through to 2031.

Phase 1: Initial rollout (2025–2026)

Phase 2: Expansion to all GST-registered businesses (2028–2031)

By April 2031, all GST-registered businesses in Singapore will be required to transmit invoice data via InvoiceNow.

For multinational enterprises, this confirms that GST InvoiceNow is not limited to new registrants — it will apply universally.

Avalara is now listed as an InvoiceNow Access Point Provider on the Singapore Peppol Authority website and is accredited for both InvoiceNow and GST InvoiceNow in Singapore.

Avalara E-Invoicing and Live Reporting (ELR):

• Supports SG PINT invoice exchange
• Provides accredited Peppol access point connectivity
• Enables GST InvoiceNow data transmission to IRAS
• Centralises multijurisdiction compliance governance
• Is available in 20 languages

For enterprise tax leaders, this means one architecture, one application, and one strategic provider supporting both invoice exchange and tax reporting across multiple countries.

Speak with Avalara to discuss e-invoicing in Singapore and across the globe or to request a demo.

InvoiceNow is Singapore’s Peppol-based e-invoicing network for exchanging invoices between trading partners. GST InvoiceNow builds on this by requiring businesses to transmit structured invoice data to IRAS for GST reporting, introducing a 5-corner model that includes the tax authority.

The mandate began with voluntary adoption in May 2025, followed by mandatory requirements for new voluntary GST registrants from November 2025. The obligation is expanding in phases to all GST-registered businesses, with full adoption required by 1 April 2031.

PINT-SG (Peppol International Invoice – Singapore) is the structured invoice format aligned to Singapore’s GST requirements. It supports GST breakdowns, validation rules, and tax category codes, ensuring invoice data aligns with IRAS reporting expectations.

Businesses must use InvoiceNow-ready solutions or accredited service providers to exchange invoices and transmit GST-relevant data to IRAS. Many enterprises will integrate their ERP with an accredited Peppol access point to meet both invoicing and reporting requirements.