GST InvoiceNow Full Roll-Out (2028-2031): What Existing Singapore Businesses Need to Know

Singapore’s GST InvoiceNow rollout includes an April 2028 phase. Existing businesses should check their own implementation date against current IRAS guidance, rather than assume 2029 is the earliest date. Voluntary and compulsory GST registrations have different entry dates. This guide explains how to prepare the company records and system change.

The full roll-out timeline

The current IRAS schedule for existing GST-registered businesses is:

Use Box 4 supplies for accounting periods ending in calendar year 2025. New compulsory GST applicants enter from 1 April 2028. Voluntary applicants enter from 1 April 2026; the November 2025 phase covered companies registering voluntarily within six months of incorporation. Check the official exclusions and your IRAS notification.

What InvoiceNow actually requires

InvoiceNow is Singapore’s nationwide e-invoicing network, built on the international Peppol standard. Rather than emailing a PDF invoice or issuing a paper invoice, a business on InvoiceNow transmits invoice data directly between accounting systems over the Peppol network. For GST purposes, the requirement means that GST-registered businesses must transmit invoice data to IRAS via InvoiceNow, giving the tax authority invoice data alongside periodic GST returns.

This is a meaningful operational shift for businesses that still generate invoices manually or through accounting software that has not yet been connected to a Peppol access point. Businesses will need either an accounting or invoicing system with native Peppol connectivity, or a registered Peppol access point provider that can bridge an existing system to the network.

Government support to offset onboarding costs

Recognising that the extension to smaller, longer-established businesses touches companies that may never have needed to modernise their invoicing systems, the Government has committed to transitional funding to help offset onboarding costs. Confirm available support, eligibility and application steps against the current official guidance before including any subsidy in the company budget.

What company secretaries and finance teams should do now

Confirm your tier

Use the applicable IRAS notification and the prescribed supplies period to document your implementation date. Keep the notification with the finance team’s readiness checklist. Do not use a current turnover forecast as a substitute for the prescribed basis.

Audit your current invoicing and accounting systems

Companies still using older accounting packages, spreadsheet-based invoicing, or systems without Peppol connectivity should start scoping a system upgrade or a Peppol access point arrangement well ahead of their implementation date, rather than waiting until the final year. This dovetails with broader digital filing obligations that Singapore companies already navigate for ACRA and IRAS purposes.

Budget for the transition, even with government support

While the transitional funding helps, it is unlikely to cover the full cost of a system change for every business, particularly those that also need staff training or process redesign. Building this into a multi-year budget, rather than treating it as a last-minute expense, will make the eventual transition considerably smoother.

How this fits with existing GST obligations

InvoiceNow adoption does not change a company’s underlying GST registration and filing obligations. Companies still file periodic GST returns (Form F5) in the usual way. The company must also submit the supporting invoice data through the required system. Businesses that have historically been relaxed about invoice record-keeping should treat this as a prompt to tighten up internal controls, since discrepancies between InvoiceNow data and filed GST returns are likely to draw closer scrutiny than in the past.

The official IRAS guidance on the InvoiceNow requirement, including the full phased timeline, is available at iras.gov.sg, and further detail on the Committee of Supply 2026 announcement can be found on the IRAS newsroom.

Practical next steps

The earliest additional phase is 1 April 2028. Allow time for system procurement, staff training and testing. Keep the implementation date and a named project owner in the readiness checklist. A short internal review now, covering current invoicing systems, Peppol readiness, and likely tier, will make the eventual transition far less disruptive.

For handling errors during onboarding, see our guide to an InvoiceNow transmission exception log. For the latest Singapore business news and regulatory updates, there are useful resources for directors and finance teams tracking changes like this one.

How Raffles Corporate Services can help

Raffles Corporate Services helps companies assess their GST InvoiceNow readiness, confirm their applicable implementation tier, and plan the accounting system changes needed well ahead of the deadline. Beyond corporate compliance, sound financial planning and investment decisions are equally important for business owners managing multi-year compliance budgets.

To speak with the team at Raffles Corporate Services, you can email [email protected] or call, SMS, or WhatsApp +65 8501 7133. We are happy to assist with any queries.

Kevin Yeo, Raffles Corporate Services