By ContactOne Team · Updated 21 May 2026 · 14 min read

This article explains what InvoiceNow is, who it currently applies to, who it will apply to and when, what it changes about your day-to-day invoicing and quarterly GST filing, and how to prepare without overcomplicating things.

What This Article Covers What InvoiceNow actually is, the rollout schedule confirmed by IRAS, what changes for new voluntary GST registrants from 1 April 2026, what existing GST-registered businesses need to plan for by April 2031, the practical workflow for invoicing and GST filing, and what to do if you are approaching the $1M turnover threshold.

What InvoiceNow Actually Is

InvoiceNow is Singapore’s national e-invoicing network, launched by IMDA (Infocomm Media Development Authority) in 2019. It is built on the international Peppol framework, which is the same standard used in much of Europe and Australia for structured e-invoicing.

In plain language: instead of sending a PDF invoice by email and hoping your customer types it into their accounts payable system correctly, your accounting software sends the invoice as structured data directly to their accounting software. The customer receives the invoice in a format their system can read automatically, with no manual data entry on either side.

The network works on what IRAS describes as a four-corner model. The supplier creates an invoice in their accounting software (Corner 1), which transmits it to their accredited Access Point (Corner 2). The Access Point sends it across the Peppol network to the customer’s Access Point (Corner 3), which delivers it to the customer’s accounting software (Corner 4). The whole exchange happens in seconds.

The GST InvoiceNow Requirement, which is what most business owners are now asking about, takes this one step further. Under the requirement, GST-registered businesses must also transmit their invoice data directly to IRAS via the InvoiceNow network. IRAS uses this data to streamline GST audits, speed up refunds, and run automated checks to flag wrongful GST charges from non-registered suppliers.

The Rollout Schedule

IRAS is rolling out the GST InvoiceNow Requirement progressively. This is the confirmed schedule based on IRAS’s own published guidance and the Committee of Supply 2026 announcement.

Date	Who it applies to
1 May 2025	Voluntary early adoption (soft launch) open to any GST-registered business.
1 November 2025	Mandatory for newly incorporated companies applying for voluntary GST registration. (A “newly incorporated” company is one incorporated within 6 months of the GST registration application.)
1 April 2026	Mandatory for all new voluntary GST registrants, regardless of incorporation date or business structure.
By 1 April 2031	All remaining GST-registered businesses must be on InvoiceNow. The schedule is being rolled out progressively, prioritising smaller businesses earlier. IRAS will notify existing GST-registered businesses (registered before 2026) of their specific implementation date by mid-2026.

The headline takeaway: if you are an existing GST-registered business that has not yet been required to onboard, you will receive your specific deadline from IRAS by mid-2026. The full implementation across all GST-registered businesses is expected to bring approximately 90,000 more businesses onto the InvoiceNow network.

Why InvoiceNow Matters for Voluntary GST Registration

For most ContactOne clients, the most immediate impact is on voluntary GST registration. From 1 April 2026, any business applying for voluntary GST registration must be ready to comply with the GST InvoiceNow Requirement before IRAS will approve the application. This is a meaningful change because it makes voluntary GST registration considerably more involved than it used to be.

Previously, voluntary GST registration was largely about whether your business model made commercial sense as a GST-registered entity. You weighed factors like the GST status of your customers and suppliers, your cashflow capability to pay GST before collecting it, and your ability to file quarterly returns on time. The decision was business-led.

Now there is an additional operational gate: your accounting or invoicing system must be InvoiceNow-Ready, you must be registered on the SG Peppol Directory with a Peppol ID, and you must have the GST InvoiceNow submission feature enabled. IRAS will not approve a voluntary GST registration if these are not in place.

Practical implication: if you are thinking about voluntary GST registration to claim back GST on a major purchase (a common scenario for commercial property buyers, for example), factor in the InvoiceNow setup time. Getting your accounting system InvoiceNow-Ready and registered on Peppol typically takes a few weeks, not a few days.

IRAS has also indicated that voluntary GST registrants who are subject to the GST InvoiceNow Requirement and remain non-compliant after registration may have their GST registration cancelled. This is not a regime where you can opt to ignore the requirement and just pay a fine.

What Changes About Your Day-to-Day Invoicing

If you are GST-registered and subject to the InvoiceNow Requirement, here is what changes in practice.

When You Issue an Invoice

Instead of sending a PDF by email, you create the invoice in your InvoiceNow-Ready accounting software and click send. The software transmits the invoice through your Access Point to the customer’s Access Point (if they are also on InvoiceNow), and simultaneously transmits the invoice data to IRAS.

If your customer is not yet on InvoiceNow, you can still send them a PDF or email copy as you always have. The data submission to IRAS happens regardless.

When You Receive an Invoice

From InvoiceNow-enabled suppliers, the invoice arrives directly in your accounting software as structured data, ready for review and reconciliation. Your software can flag potential issues automatically, such as a supplier who appears to be charging GST but is not actually registered for GST.

This last point is genuinely useful. Wrongful GST charges from non-registered suppliers are a recurring problem that businesses often only discover during an IRAS audit, by which time the input tax has already been claimed and needs to be reversed. InvoiceNow’s built-in checks catch this at the point of receipt.

When You File Your Quarterly GST Return

This is where the time saving compounds. Because IRAS already has your invoice data, the GST F5 return becomes substantially more automated. Your accounting software prepares the return from data that has already been validated, the figures pre-populate, and the manual transcription work that used to take a couple of hours each quarter largely disappears.

IRAS has indicated that GST refunds will also be processed faster for InvoiceNow-compliant businesses, because IRAS can validate the underlying transactions in advance rather than requesting documentation after a claim is filed.

If You Are Approaching the $1 Million Threshold

Compulsory GST registration is triggered when your taxable turnover for the past 4 quarters exceeds $1 million, or when you can reasonably expect it to exceed $1 million in the next 12 months. If you are watching your sales head toward this threshold, the InvoiceNow Requirement adds a planning dimension that did not exist before.

The compulsory GST registration process gives you 30 days from the date the registration liability arises to apply. Most of the existing GST-registered business population is being moved to InvoiceNow progressively until April 2031, and IRAS will notify businesses of their specific deadlines by mid-2026. However, businesses that become newly GST-registered (whether voluntarily or compulsorily) under the current rules need to engage with InvoiceNow much sooner.

If you can see compulsory GST registration coming in the next 12 to 24 months: Start the InvoiceNow conversation now with your accountant or corporate service provider. Migrating accounting systems while simultaneously taking on quarterly GST filing obligations is unnecessarily stressful when both can be staged properly with a few months of lead time.

How to Become InvoiceNow-Ready: The Three Steps

IRAS has set out a straightforward three-step process. Your corporate secretary or accountant typically handles step 1 and step 2 on your behalf, but it is useful to know what is happening.

Step	What happens
Step 1	Choose an InvoiceNow-Ready Solution. Check IMDA’s accredited list of InvoiceNow-Ready Solution Providers (IRSPs) and pick one your business can work with. Many mainstream accounting platforms used in Singapore are already on the list. There are also Free-of-Charge solution packages available for GST-registered businesses, which are worth considering for smaller operations.
Step 2	Get an Access Point and Peppol ID. Approach an IMDA-accredited Access Point Provider to register your business in the SG Peppol Directory using your UEN. This is what connects you to the InvoiceNow network.
Step 3	Enable GST InvoiceNow submission. Within your accounting software, switch on the feature that transmits invoice data to IRAS. Your IRSP can assist with the configuration.

Grants and Support Available

At the Committee of Supply 2026, IRAS and IMDA announced a new grant of up to $5,000 for early adopters of the GST InvoiceNow Requirement. The specifics on eligibility and application are being released by IMDA and IRAS, but the direction is clear: the government is incentivising earlier rather than later adoption.

For businesses that were already on the InvoiceNow pilot (which ran between September 2020 and June 2023 with companies like Sheng Siong Group), the requirement is largely a continuation of existing practice. For everyone else, the grant materially reduces the cost of getting set up.

Common Questions We Get from Clients

Does InvoiceNow replace GST filing?

No. You still file your quarterly GST F5 return through myTax Portal. What changes is that the return is largely pre-populated from data IRAS already has, rather than being assembled from scratch each quarter.

Do I need to send invoices in InvoiceNow format to all my customers?

Your obligation is to transmit the invoice data to IRAS. If your customer is on InvoiceNow, they receive the structured invoice directly. If not, you can continue to send them a PDF or email copy. Over time, as more businesses come onboard, more of your customer base will be receiving the structured version.

What if my accounting software is not on the IRSP list?

You have two options. Either work with your software vendor to confirm if and when they plan to become an IRSP, or migrate to an accounting solution that is already accredited. For smaller businesses, the Free-of-Charge solution packages mentioned above may be a practical answer. For most established businesses on Xero, QuickBooks Online, and other mainstream platforms, the platforms are already accredited or have InvoiceNow capability built in.

What if I am already GST-registered but have not heard from IRAS?

IRAS will be notifying existing GST-registered businesses (registered before 2026) of their specific implementation deadline by mid-2026. The schedule prioritises onboarding of smaller businesses earlier. In the meantime, IRAS has published an Excel calculator that lets you self-assess your applicable implementation date based on your total annual supplies in 2025.

Is InvoiceNow only for GST-registered businesses?

No. InvoiceNow as a network is open to any Singapore business, and many non-GST-registered businesses have adopted it for the efficiency benefits in their accounts payable and receivable processes. The GST InvoiceNow Requirement specifically applies to GST-registered businesses, but you can adopt the underlying e-invoicing network even if you are not yet GST-registered.

What This Means If You Are Currently Weighing GST Registration

The decision to register for GST voluntarily has always been a cost-benefit exercise. The InvoiceNow Requirement adds two new factors to consider.

On the cost side: there is a setup effort to get your accounting system InvoiceNow-Ready, register with an Access Point, and configure the GST submission feature. For most businesses this is a few weeks of preparation rather than a major project, but it is not zero.

On the benefit side: faster GST refunds, automated wrongful-GST-charge detection, and substantially less manual work each quarter at GST filing time. For businesses with high transaction volume, these operational benefits can outweigh the setup effort within the first year.

The other consideration is timing. If compulsory GST registration is coming for you anyway (because your turnover is heading toward the $1 million threshold), there is little advantage to delaying the InvoiceNow setup. The work has to be done eventually, and doing it during a planned voluntary registration is less stressful than doing it under the 30-day compulsory registration clock.

How ContactOne Helps

For ContactOne accounting and GST clients, we handle the InvoiceNow setup as part of our GST registration service where applicable. This includes advising on the right InvoiceNow-Ready Solution for your transaction volume and accounting setup, coordinating with your chosen Access Point Provider, and ensuring the GST InvoiceNow submission feature is correctly configured before your first GST return falls due.

For businesses considering voluntary GST registration, we run through the cost-benefit conversation in light of the new InvoiceNow Requirement and help you set realistic expectations on timeline and setup effort. For businesses approaching the compulsory threshold, we help with the planning conversation so the InvoiceNow setup is in place before the registration deadline.

Singapore’s GST regime has, over the past few years, moved from a relatively manual process to a substantially automated one. For businesses that engage with the change properly, this is genuinely good news. The compliance burden gets lighter once the systems are in place. The risk is treating InvoiceNow as a tick-box exercise and discovering at year-end that the configuration is not quite right.

Considering GST registration or approaching the threshold? We can run through the InvoiceNow implications for your specific business in a 15-minute conversation. No obligation. WhatsApp Our Accounting Team View GST Registration Services

Sources and Further Reading

All facts and dates in this article are drawn from official Singapore Government sources. For the most up-to-date position, refer directly to:

• IRAS: GST InvoiceNow Requirement — the primary reference page covering scope, who it applies to, and how to prepare
• IRAS: Responsibilities of a GST-registered Business — details on the 1 November 2025 and 1 April 2026 obligations for voluntary registrants
• IRAS Newsroom: Committee of Supply 2026 announcement — the full rollout schedule to all GST-registered businesses by April 2031, and details of the $5,000 early adopter grant
• IRAS Newsroom: Implementation of InvoiceNow for GST-Registered Businesses — the original phased rollout announcement
• IRAS e-Tax Guide: Adopting GST InvoiceNow Requirement — the technical reference for the four-corner Peppol model and full requirements

This article reflects the position published on iras.gov.sg as at May 2026. Specific compliance questions, particularly around eligibility for the early adopter grant or the implementation date applicable to your business, should be directed to IRAS or to a qualified corporate service provider.