Electronic invoice in Singapore
The Definitive Guide to Singapore’s GST InvoiceNow: Navigating the 5-corner Peppol reporting model, PINT-SG compliance, and phased adoption for GST-registered businesses.
Singapore is not building a clearance system. The foundation is InvoiceNow, a nationwide document exchange network on the Peppol four-corner model. For GST purposes a fifth corner is added — transmission of invoice data to the tax authority IRAS through an IMDA-accredited Access Point. No invoice waits for approval, an authorisation number or an IRAS QR code.
The distinction that decides most implementation questions: the Singapore mandate is an obligation on certain GST-registered businesses to use an InvoiceNow-ready solution and report invoice data to IRAS. It is not an absolute obligation to deliver a structured XML to every buyer. If your counterparty is not on InvoiceNow, a PDF or paper document is still fine — but the transaction must be recorded in an InvoiceNow-ready system and the data reported.
Singapore is phasing the requirement by taxpayer group over six years, deliberately slowly. Two phases are already behind us.
IMDA launched the Peppol-based national network in 2019. From 20 January 2020 the government began accepting supplier invoices through InvoiceNow. See B2G.
GST-registered businesses wishing to adopt ahead of their own phase could begin transmitting from this date.
Companies voluntarily registering for GST within six months of incorporation came into the requirement.
Every business applying for voluntary GST registration is now inside the requirement — which is why the registration consequence matters more than any fine.
Businesses applying for compulsory GST registration from that date, together with existing GST-registered businesses with annual taxable supplies up to S$200,000.
Existing businesses with total annual supplies up to S$1 million from 1 April 2029, and up to S$3 million from 1 April 2030.
Full coverage of GST-registered businesses. IRAS determines which band an existing GST payer falls into using its annual supplies for the relevant accounting periods ending in the 2025 calendar year.
Two boundaries worth stating plainly. The requirement applies to GST-registered businesses — companies not registered and not required to register are not in the general schedule. And because the band test uses 2025 figures, a business's position is already determined: growth after 2025 will not move it into an earlier phase.
The base exchange is the standard four corners — supplier, supplier's Access Point, buyer's Access Point, buyer — using Peppol for participant discovery, routing and secure transmission. GST InvoiceNow adds IRAS as a fifth corner, connected through a dedicated C5 interface.
On the buyer's side there is a further flow: after recording or accepting an incoming invoice, the buyer's accounting system can report the purchase to IRAS, including the tax classification and the input tax being claimed.
If the buyer is not on InvoiceNow, the supplier may send a PDF, issue a paper invoice or receipt, use a POS document or any other commercial channel. The transaction must then be recorded in the InvoiceNow-ready accounting system, and the structured data transmitted to IRAS through an accredited Access Point. That flow is called solution-extracted invoice data submission.
Decentralised Peppol exchange plus CTC reporting to IRAS on a five-corner model — with no prior clearance. It is not the Italian SdI and not a Latin American pre-authorisation system: nothing is validated before the buyer receives it.
Since 20 January 2020 the government has accepted supplier invoices through InvoiceNow. Invoices do not go to each agency individually: they are sent to the central Peppol endpoint of the Accountant-General's Department, which then routes the document to the relevant public body.
The government has stated an intention to make InvoiceNow the default channel for all registered business suppliers and eventually replace Vendors@Gov. But that wording remains a plan — "within the next few years" — with no fixed date on which alternative channels close. Vendors@Gov is still in use and its documentation was being updated in June 2026.
An invoice that fails those checks can be rejected by the receiving agency's system. That is a procurement and business validation outcome — not IRAS tax clearance, which does not exist here. The two failure modes look similar in a support ticket and need to be diagnosed differently.
In B2B, a buyer without a Peppol ID does not release a connected supplier from its reporting duty — but it does not make the commercial transaction impossible either. Send the document by whatever channel works and report the data.
There is no consumer e-invoice delivery mandate. A consumer may receive an ordinary receipt, a simplified tax invoice, a POS receipt, a PDF or a paper document, and needs no Peppol ID. In the records submitted to IRAS, the name and UEN fields for a private individual may be filled with NA in the cases provided for.
POS receipts, simplified invoices and small purchases may be aggregated under IRAS rules rather than transmitted as individual full Peppol transactions. So what B2C creates is a supplier GST reporting obligation — not an obligation to hand the customer a structured invoice.
In February 2024 the earlier Singapore Peppol BIS Billing 3.0 specification was replaced by PINT-SG — the Peppol International Invoice, Singapore. It is the mandatory profile for GST InvoiceNow, and the official syntax is OASIS UBL 2.1 Invoice and CreditNote.
On EN 16931. The former Singapore Peppol BIS Billing 3.0 used the Peppol Billing semantic model and carried an EN 16931 conformance identifier. Today's PINT-SG is based on the international Peppol PINT model and adapted to Singapore GST rules — and Singapore does not establish EN 16931 as a mandatory national standard in the legal sense EU member states do. High semantic compatibility with the Peppol ecosystem, yes; but the binding profile is PINT-SG.
UN/CEFACT CII is not published as a mandatory or equivalent InvoiceNow profile. A service provider may convert a client's internal formats — CII, CSV, JSON, ERP structures — but the document travelling on the Singapore Peppol profile must be PINT-SG in UBL.
A PDF emailed to the buyer is not an InvoiceNow e-invoice, because it carries no structured machine-readable data. But PDF is not prohibited: it can be the commercial document for a buyer who is not on InvoiceNow, provided the data is captured in an InvoiceNow-ready solution and reported. In B2G a PDF, JPEG or PNG may be attached to the structured Peppol invoice — the attachment never replaces the PINT-SG XML.
IMDA has flagged one practice specifically: an Access Point must not present a simple conversion of a received PDF into a Peppol invoice as genuine network exchange on the original supplier's behalf. Off-network documents belong in the solution-extracted data flow. Any product design that quietly "upgrades" PDFs into Peppol traffic is on the wrong side of that line.
Singapore participants are addressed under Electronic Address Scheme 0195, using SGUEN plus the entity's Unique Entity Number.
The UEN is also how the Singapore supplier is identified in the data submitted to IRAS — which matters where an overseas shared service centre transmits on a Singapore entity's behalf. That is technically permitted, but the transmission must run through an IMDA-accredited Access Point and must correctly identify the Singapore supplier by its UEN.
Peppol is the principal infrastructure for structured exchange in InvoiceNow. But GST InvoiceNow reaches further than the network itself: transactions delivered to the buyer outside Peppol are still captured, because their data can be reported to IRAS through the same accredited Access Point.
The Infocomm Media Development Authority (IMDA) is the national Peppol Authority. It holds the agreement with OpenPeppol, defines the Singapore Peppol Authority Specific Requirements, and accredits Access Point and SMP providers.
There is no separate cross-border mandate. The obligation follows the Singapore taxpayer's own phase. If the overseas buyer is on Peppol and its national or international profile is PINT-compatible, the invoice can travel over the network; if not, send it by email or another channel and report the data where the transaction goes into the GST return.
For imported goods the import permit may remain the primary document for input GST, rather than invoice data reported through InvoiceNow. Purchases from a supplier not registered for Singapore GST may fall outside the ordinary purchase-invoice reporting category, with reverse charge and Overseas Vendor Registration rules applying separately.
Some wholly foreign companies are excluded from the mandate, including certain Overseas Vendor Registration entities and companies registered solely because of reverse charge. But a foreign company with a Singapore branch or local establishment is not automatically excluded, and a Singapore company with an overseas branch remains covered in respect of its Singapore business.
Singapore is not an EU member state, so the ViDA timings and rules for intra-EU B2B digital reporting are not a Singapore legal mandate. For a Singapore company, transactions with the EU are ordinary cross-border exports or imports under Singapore GST law.
An existing European Peppol accreditation is not sufficient. A provider wishing to offer Access Point services in Singapore must comply with the Peppol Authority Specific Requirements and obtain the Peppol Service Provider Accreditation instituted by IMDA. IMDA publishes accreditation guides for both Access Point providers and InvoiceNow-Ready Solution Providers.
The architectural point that decides project scope: your solution must handle far more than sent and received Peppol invoices. It needs at least four additional categories — off-network sales, off-network purchases, POS and B2C aggregation, and the export and import tax scenarios. In the Singapore model the measure of compliance is the completeness of the GST return data, not the number of Peppol documents moved.
To ease onboarding and encourage early adoption, the government introduced transitional funding to offset onboarding costs:
This is worth raising with a client early rather than late: the funding is framed around transition, and a business that waits until its own phase begins in 2028 or beyond is not obviously better placed than one that moves now.
InvoiceNow changes nothing about record-keeping, and the point deserves emphasis because the five-corner model invites the opposite assumption. Data received by IRAS through InvoiceNow does not replace the taxpayer's own accounting records.
Because off-network transactions are common by design in Singapore, the archive has to hold two shapes of evidence at once: the PINT-SG XML for network invoices, and the PDF, paper or POS document plus the extracted data for everything else.
IRAS has published no single fixed penalty — no set amount per invoice not transmitted through InvoiceNow. It describes a phased and "calibrated" approach to enforcement, particularly in the early stages, where an error is made in good faith, is not the result of negligence, can be explained and evidenced from the accounting records, and is corrected by the taxpayer.
The absence of a fixed sum does not make the obligation voluntary.
The sharpest consequence is not a fine. For businesses registering voluntarily for GST and caught by the mandate, the GST registration application may not be approved — and a registration already granted may be cancelled or withdrawn if the InvoiceNow conditions are not met. That is the most concrete consequence IRAS names, and since 1 April 2026 it reaches every voluntary registrant.
Once the rollout is complete, IRAS may also act against businesses that fail to onboard on time, systematically fail to transmit, transmit materially incomplete or inaccurate data, do not remedy breaches, or fail to keep supporting documents. Ordinary tax penalties apply alongside for an incorrect GST return, understated output tax, an unjustified input tax claim or inadequate record-keeping.
No. To claim input GST the buyer needs proper support — a valid tax invoice, a customer accounting tax invoice where applicable, an import permit for imported goods, or another prescribed GST document. The invoice does not have to exist as PINT-SG XML: a paper or PDF tax invoice can support the claim if it carries the required particulars and the other GST Act and Regulations conditions are met.
IRAS also confirms that a Peppol invoice can be a valid tax invoice even without the literal words "Tax Invoice", provided the other mandatory details are present and the general conditions for deduction are met. Reporting through InvoiceNow is a separate digital reporting obligation — not the sole legal basis for input GST deduction.
Singapore is a Peppol market, which makes it more familiar than most — but GST InvoiceNow is a reporting project as much as an exchange project:
0195:SGUEN, with the Singapore supplier correctly identified in IRAS submissionsSingapore runs decentralised Peppol exchange with a tax reporting corner bolted on — four corners for the invoice, a fifth for IRAS, and no clearance anywhere. The mandate binds GST-registered businesses in phases running from November 2025 to full coverage on 1 April 2031, with the band for existing registrants already fixed by their 2025 supplies.
The design principle worth carrying into every conversation: what Singapore requires is complete GST data at IRAS, not that every invoice travel over Peppol. Off-network sales, off-network purchases, POS aggregation and the export and import scenarios are not edge cases here — they are core scope.
For a European Access Point this is a familiar architecture with an unfamiliar accreditation. IMDA accreditation is required and does not follow from a European one; PINT-SG, the central SMP and the IRAS C5 interface all have to be implemented and tested locally. The compensations are real, though — S$10,000 minimum capital, no local entity requirement in the published rules, and government funding on the client side.