InvoiceNow for GST-Registered SMEs: Find Your Deadline

InvoiceNow for GST-registered SMEs: what changes?

InvoiceNow is Singapore's nationwide e-invoicing network, introduced by IMDA in 2019 and based on the Peppol standard. A structured e-invoice can move from a supplier's finance system to a customer's finance system; under the GST InvoiceNow Requirement, relevant invoice data also goes to IRAS.

That is different from creating an invoice in Word, saving it as a PDF and attaching it to an email. A PDF may still be how a customer or supplier works, but your InvoiceNow-Ready Solution must hold the underlying fields and transmit the required data. IRAS calls this the solution-extracted method when an invoice was issued outside the InvoiceNow network and then recorded in the ready solution.

You continue to issue and process invoices without waiting for IRAS to approve each one. The requirement is to submit the relevant data by the earlier of the date you file the relevant GST return or that return's filing due date.

InvoiceNow does not prepare a correct GST return by itself. IRAS explicitly keeps the existing duties in place: file accurately, retain supporting records and comply with invoicing rules. Treat InvoiceNow as a new data rail inside the finance process, not a replacement for accounting judgement.

When must your business comply with InvoiceNow?

Use the first row that describes your business. The dates and thresholds below are from IRAS as of October 2026.

For existing businesses, read the thresholds cumulatively: the smallest group moves first. A business at or below S$200,000 starts in 2028; one above S$200,000 but at or below S$1 million starts in 2029; one above S$1 million but at or below S$4 million starts in 2030.

“Total annual supplies” is not simply the revenue in your latest management accounts. IRAS defines it as the total standard-rated, zero-rated and exempt supplies in Box 4 across all prescribed accounting periods ending in calendar year 2025. Use your IRAS notification or its implementation-date calculator rather than guessing from current turnover.

IRAS excludes overseas entities, including businesses under the Overseas Vendor Registration regimes, and businesses registered for GST wholly because of the Reverse Charge regime. A normal local GST-registered business that also has reverse-charge transactions is not excluded merely for that reason.

What invoice data must you send to IRAS?

The practical test is whether an invoice or equivalent document supports a transaction reported in the GST return, then whether IRAS lists that transaction as excluded.

The scope is broader than invoices received through Peppol. If a supplier emails a paper or PDF invoice and you record it in the InvoiceNow-Ready Solution, the solution-extracted data can still be transmitted to IRAS. Likewise, a sale to a customer who is not on InvoiceNow does not automatically sit outside the requirement.

Supporting files such as shipping documents do not have to accompany the invoice-data submission. IRAS says you must still retain them and produce them when requested.

How do you automate InvoiceNow without losing control?

Use these steps in order so the legal date, system connection, invoice paths and filing controls stay aligned.

• 1. Confirm the legal start date: Save the IRAS notification, identify the 2025 Box 4 figures behind it and name one person accountable for readiness.
• 2. Check the system you already use: Find it on IMDA's accredited InvoiceNow-Ready Solutions list. If it is not there, choose a listed solution or speak to an IMDA-accredited Access Point about the connection path.
• 3. Register the business on the network: Ask the provider or Access Point to register your UEN in the SG Peppol Directory and issue the Peppol ID. IMDA says Singapore-registered businesses need Corppass for the know-your-customer process.
• 4. Map every invoice path: List Peppol sales, non-Peppol sales, Peppol purchases, emailed supplier PDFs, point-of-sale totals, petty cash, debit notes and credit notes. Give each path an owner and an in-scope or excluded rule.
• 5. Clean the fields before connecting them: Fix duplicate suppliers, missing UENs, inconsistent tax codes, incomplete invoice references and unclear posting dates. Automation moves bad data faster if these rules are not settled first.
• 6. Activate and test the IRAS feature: Run representative transactions through the ready solution, check submission acknowledgements, test rejected records and document how the team recovers when a service is unavailable.
• 7. Reconcile before filing: Compare submitted invoice data with the ledger and relevant GST return. Resolve exceptions before the earlier of the return filing date and filing deadline.

The statutory connection is only one part of the job. A useful finance workflow also collects documents from email or WhatsApp, reads the fields, checks the supplier and tax code, detects duplicates, routes an exception to the right person and matches the final posting to payment. That surrounding workflow is where finance and accounting automation removes retyping without giving away financial judgement.

Where should a person still approve the invoice flow?

Routine movement can be automated; judgement and irreversible changes should remain visible.

This is the control line to insist on whether you use a portal, an accounting product or a custom workflow. “Automated” should mean the routine path is inspectable and repeatable—not that the system quietly invents a GST treatment or accepts a bank-account change.

What does an automated InvoiceNow workflow look like?

Take a Singapore wholesaler that receives supplier bills as a mix of Peppol records and emailed PDFs, while sales invoices are raised from confirmed orders. Today, staff may download attachments, type supplier and GST fields into the ledger, check for duplicates, chase missing purchase-order references and later compare the ledger with the GST working papers.

In the redesigned flow, Peppol invoices arrive as structured records. Emailed PDFs are captured into the same review queue. The workflow validates the supplier against the approved master record, checks required fields, suggests the established GST code and looks for a matching order or receipt. Clean items are prepared for posting; low-confidence fields, duplicates and changed payment details stop for review.

Once approved, the accounting record becomes the source for solution-extracted submissions where needed. The ready solution sends the data to IRAS and stores the acknowledgement. Before the GST return is filed, a control report compares the submitted population with the ledger and lists the exceptions. The finance lead reviews a short queue instead of rebuilding the population from PDFs.

InvoiceNow supplies the regulated transport and data format. The capture, validation, approval and reconciliation workflow is what removes manual work. That distinction matters when comparing a free compliance portal with a connected finance process: both may submit compliant data, but only one may remove the copying around it.

The same review-first pattern is proven in Biks' finance work. In Law Firm Bank Reconciliation: 20+ Hours to Under 30 Minutes, four people had spent more than twenty hours a week on reconciliation; the recurring work now takes under thirty minutes to review. InvoiceNow is a different workflow, but the operating principle is the same: automate production and keep people on validation.

Should you use a free portal, accounting software or a custom connection?

Choose for the operating workflow, not only for the act of submitting invoice data.

IRAS says free-of-charge packages with basic compliance capabilities are available until 31 March 2031; the currently listed packages run until 31 March 2027, with the next list to follow. A free portal can be enough if invoices are few and the process is simple. It can also leave staff copying the same data between email, spreadsheets and the portal.

Using an InvoiceNow-Ready accounting solution is usually the cleaner path when the ledger already contains the invoice population. A custom connection becomes reasonable when invoices originate in another operational system, several entities share a process or the existing approval controls must remain in place. Compare each route with the measured hours of manual entry and review, and with the full cost of hiring another administrator—not only the subscription fee.

What InvoiceNow support can an SME use?

As of October 2026, IRAS lists a GST InvoiceNow Transition Grant of S$1,000 for SMEs with annual supplies of S$4 million or less. Larger businesses are listed for a S$5,000 transition grant, and IMDA directs businesses to its grant page for full eligibility and claim details. Do not commit spending on the headline amount alone; confirm the current conditions first.

IMDA and IRAS also list free-of-charge InvoiceNow-Ready packages through March 2031. “Free” refers to the package offered for the requirement, not necessarily every accounting, integration, migration or support need around it. Ask what is included, what happens after the free period, how data is exported and who supports rejected submissions.

Start before the deadline year. The calendar needs room for cleanup, provider onboarding, Peppol registration, test transactions, staff training and at least one full GST-cycle reconciliation.

What should your SME do next?

• This week: Confirm the IRAS implementation date, the 2025 Box 4 total behind it and whether the current finance solution is on IMDA's ready list.
• This month: Map every sales, purchase and adjustment path; mark in-scope data, exclusions, owners and approval points.
• Before onboarding: Clean supplier identities, UENs, invoice references and GST codes, then choose the portal, ready accounting solution or Access Point route.
• Before activation: Test Peppol and non-Peppol transactions, corrections, rejected records, acknowledgements, downtime and the reconciliation to the GST return.

The compliance deadline is the backstop, not the project plan. The better target is a full invoice cycle that the finance team can explain: where each record entered, which checks ran, who approved an exception, whether IRAS acknowledged it and how the submitted population ties back to the books.