InvoiceNow Mandatory For New GST Registrants | Singapore’s E-Invoicing Rollout Timeline 2025-2026

As a serious compliance point for voluntary GST registration, the InvoiceNow mandatory Singapore GST 2026 rules must be considered. Singapore is moving GST reporting closer to real-time invoice data submission. New voluntary GST registrants are among the first groups affected.

InvoiceNow is Singapore’s nationwide e-invoicing network based on the international Peppol standard. It lets businesses send and receive invoices in a structured digital format, which reduces manual handling and improves processing efficiency. IMDA introduced InvoiceNow in 2019, and IRAS is now using it to support digital tax administration. 

What Is The GST InvoiceNow Requirement?

The GST InvoiceNow Requirement means selected GST-registered businesses must transmit invoice data to IRAS. This must be done through the InvoiceNow network using InvoiceNow-Ready Solutions. This does not mean the business only sends invoices to IRAS. It means invoice data linked to GST reporting must be submitted through the approved digital network.

This is a big change for SMEs because invoicing, accounting software, GST reporting, and record keeping must now work together. A business can no longer treat e-invoicing as only a finance team upgrade. It becomes part of GST registration readiness.

Who Must Comply In 2025 And 2026?

The first mandatory phase started on 1 November 2025. It applies to companies that register for GST voluntarily within 6 months of incorporation.

The next important date is 1 April 2026. All new voluntary GST registrants must submit invoice data directly to IRAS through the InvoiceNow network. This applies regardless of their incorporation date or business structure. IRAS defines new voluntary GST registrants as businesses that apply for voluntary GST registration on or after 1 April 2026. 

GST E-Invoicing Mandate Singapore Phased Rollout

IRAS states that existing GST-registered businesses registered before 2026 will be informed of their mandatory implementation date by mid-2026. Existing GST businesses can also use IRAS’ implementation date calculator to self-check timing. 

What Data Must Be Sent To IRAS?

Businesses covered by the GST InvoiceNow Requirement must transmit invoice data for transactions reported in the GST return. This includes standard-rated supplies, zero-rated supplies, exempt supplies, standard-rated purchases, and zero-rated purchases.

The data can come through invoices or equivalent billing documents. IRAS lists examples such as sales invoices, tax invoices, simplified tax invoices, serially numbered receipts, debit notes, and credit notes. Businesses can also aggregate certain types of data, such as point-of-sale supplies, simplified tax invoice supplies, and petty cash purchases.

Some transactions are excluded. These include reverse charge transactions, import permits, exempt financial services, and digital payment token exchanges. They also cover certain transactions reported only for GST purposes without an underlying supply or purchase.

How To Prepare For Peppol E-Invoicing IRAS Submission

Key preparation steps include:

• Check if the accounting or finance software is an accredited InvoiceNow-Ready Solution Provider.
• Register the business in the SG Peppol Directory using the UEN and obtain a Peppol ID.
• Enable the GST InvoiceNow submission feature inside the software or through an accredited Access Point Provider.
• Test invoice creation, purchase invoice handling, credit notes, debit notes, and GST classification before filing starts.
• Confirm who inside the company reviews wrong GST charges, invoice errors, and rejected submissions.

IRAS notes that businesses using in-house enterprise solutions may need 3 to 12 months for system connection to IRAS. Many off-the-shelf tools may be easier to activate, but businesses should still plan early. 

InvoiceNow Ready Software List Singapore

The InvoiceNow ready software list Singapore should be checked through IMDA and IRAS guidance. IRAS advises businesses using off-the-shelf accounting or finance solutions to check their provider’s status. They should verify if their preferred solution is listed as an IMDA-accredited InvoiceNow-Ready Solution Provider. They may also consider free-of-charge solution packages for GST-registered businesses. 

This is useful for SMEs that do not want a heavy system implementation. IMDA notes that InvoiceNow services range across free e-invoicing portals, accounting solutions, and customised systems. More than 63,000 businesses were already on the network when the 2026 extension was announced. 

Due Date For Invoice Data Transmission

Invoice data must be transmitted to IRAS by the earlier of two specific dates. These are either the date the relevant GST return is filed or its official filing due date. The relevant GST return is the return covering the accounting period in which the transaction date falls. 

This means SMEs should not wait until after GST filing to clean up invoice data. If invoice data is incomplete or inconsistent, the GST return process can become messy. The accounting team should review invoice records before filing, not after the return has already gone in.

Common Mistakes New GST Registrants Should Avoid

New GST registrants often focus on GST approval and forget the systems behind compliance. That can create problems once invoices start moving.

Avoid these mistakes:

• Applying for voluntary GST registration without checking InvoiceNow readiness.
• Choosing software that cannot support GST InvoiceNow submission.
• Treating the Peppol ID as a one-time setup and ignoring invoice workflow testing.
• Assuming InvoiceNow removes normal GST record keeping duties.
• Waiting until the GST return deadline before checking invoice data.

IRAS makes it clear that GST-registered businesses remain responsible for GST obligations, including accurate invoices and GST returns. It also states that InvoiceNow does not remove existing record keeping duties. 

Conclusion

InvoiceNow mandatory Singapore GST 2026 rules make e-invoicing part of GST readiness for new voluntary registrants. Businesses should check software, Peppol registration, invoice data quality, and GST return workflows before applying or filing.

A smooth GST InvoiceNow setup requires more than just software activation. At Arnifi, our expert team helps companies properly connect registration, accounting records, GST filing, and compliance workflows. With the right setup, SMEs can reduce filing errors and prepare for IRAS requirements. They can also build cleaner finance operations as they grow.

FAQs

1. Is InvoiceNow Mandatory For All New GST Registrants In 2026?

InvoiceNow is mandatory for all new voluntary GST registrants. This applies to those who apply for voluntary GST registration on or after 1 April 2026. New compulsory GST registrants come into the mandatory rollout later, starting 1 April 2028. 

2. What Is Peppol E-Invoicing In Singapore?

Peppol e-invoicing allows businesses to send and receive structured digital invoices through the InvoiceNow network. Singapore’s InvoiceNow network is based on the international Peppol standard. 

3. When Must Invoice Data Be Sent To IRAS?

Invoice data must be transmitted by the earlier of two dates. These are the GST return filing date or the filing due date for the relevant accounting period.

4. Does InvoiceNow Remove Normal GST Record Keeping Duties?

No. IRAS states that businesses must continue to follow existing record keeping requirements. InvoiceNow data submission does not replace normal GST record keeping duties.