Guide · E-invoicing
InvoiceNow and the GST InvoiceNow requirement: a guide for Singapore businesses
What is InvoiceNow?
InvoiceNow is Singapore's nationwide e-invoicing network, run by IMDA (Infocomm Media Development Authority) on the open Peppol standard. Invoices travel directly between businesses' finance systems as structured data — no PDFs, no re-typing.
Because the invoice arrives as data, the buyer's system can match it to the purchase order and post it without anyone typing it in. Peppol carries more than invoices: credit notes, purchase orders and order responses travel the same way.
What is the GST InvoiceNow requirement?
Under IRAS's GST InvoiceNow requirement, GST-registered businesses send their invoice data to IRAS (Inland Revenue Authority of Singapore) through InvoiceNow, using an InvoiceNow-ready solution connected to an IMDA-accredited Access Point. It is being phased in from November 2025, reaching every GST-registered business by April 2031.
In practice, your InvoiceNow-ready solution sends a copy of your invoice data to IRAS through your Access Point as part of normal invoicing — there is no separate upload. Your GST returns stay as they are.
When does my business need to comply?
IRAS is phasing the requirement in by how and when a business registered for GST, and for existing businesses by their total annual supplies:
| From | Who |
|---|---|
| 1 May 2025 | Any GST-registered business may start voluntarily |
| 1 Nov 2025 | Newly incorporated companies registering for GST voluntarily within 6 months of incorporation |
| 1 Apr 2026 | Every new voluntary GST registration |
| 1 Apr 2028 | New compulsory GST registrants, and existing GST-registered businesses with total annual supplies of S$200,000 or less |
| 1 Apr 2029 | Existing GST-registered businesses with total annual supplies of S$1 million or less |
| 1 Apr 2030 | Existing GST-registered businesses with total annual supplies of S$4 million or less |
| 1 Apr 2031 | All remaining GST-registered businesses (annual supplies above S$4 million) |
What do I need to comply?
- A Peppol IDYour business is registered on the InvoiceNow network, usually under its UEN.
- An InvoiceNow-ready solutionSoftware that creates and reads Peppol e-invoices and transmits invoice data to IRAS.
- An IMDA-accredited Access PointThe gateway that carries your documents on the network — HeyInvoice uses SESAMi.
- Invoice data to IRASOnce GST InvoiceNow submission is switched on, invoice data goes to IRAS through the Access Point as invoices are sent.
Key terms: Peppol, Access Point, IRSP, PINT SG and C5
The words you'll meet when you get ready for InvoiceNow:
| Term | What it means |
|---|---|
| Peppol (Peppol network) | The international open standard and network for exchanging e-invoices and other business documents between companies' systems. InvoiceNow is Singapore's Peppol network. |
| IMDA (Infocomm Media Development Authority) | The Singapore government agency that runs InvoiceNow as the country's Peppol Authority. It accredits Access Points and InvoiceNow-Ready Solution Providers. |
| IRAS (Inland Revenue Authority of Singapore) | Singapore's tax authority. Under the GST InvoiceNow requirement it receives invoice data through the InvoiceNow network. |
| Peppol Access Point (Access Point (AP)) | An IMDA-accredited gateway that sends and receives documents on the InvoiceNow network for you. HeyInvoice runs on SESAMi, an IMDA-accredited Access Point. |
| InvoiceNow-Ready Solution Provider (IRSP) | IMDA's accreditation for software connected to InvoiceNow through an accredited Access Point that supports the GST InvoiceNow requirement. HeyInvoice's IRSP accreditation is in progress. |
| Peppol ID | Your business's address on the InvoiceNow network — for Singapore companies usually built from the UEN (for example 0195:SGUEN…). |
| PINT SG (Peppol BIS) | The document formats used on InvoiceNow: PINT SG (Peppol International Invoice, Singapore) and SG Peppol BIS 3.0. HeyInvoice sends both. |
| C5 (fifth corner) | In Peppol's five-corner model the tax authority is the fifth corner. "C5 submission" is how invoice data reaches IRAS through your Access Point. |
| UEN (Unique Entity Number) | The registration number ACRA gives every Singapore business. It identifies you on InvoiceNow and fills in company details automatically in HeyInvoice. |
Do I have to replace my accounting or ERP system?
No. Many businesses keep their accounting, ERP or POS system and add an InvoiceNow-ready solution beside it — connected through an API or a file import — so invoices still start where they do today.
What matters is that every invoice you issue, and the supplier invoices you record, reach InvoiceNow and IRAS in the right format with the right GST treatment on each line.
How to get ready — a five-step plan
- Check your dateFind your phase in the table above from your GST registration type and total annual supplies.
- Map your invoicesList where sales invoices, credit notes and supplier invoices are created today — accounting system, ERP, POS, spreadsheets.
- Choose a solutionPick an InvoiceNow-ready solution that connects to those systems and to an IMDA-accredited Access Point.
- Register and testGet your Peppol ID, connect your systems, and send test documents before your start date.
- Switch on IRAS submissionTurn on GST InvoiceNow submission and check the data IRAS receives against your GST records.
Sources
- IRAS — GST InvoiceNow Requirement
- IRAS — FAQs for GST InvoiceNow Requirement (PDF)
- IMDA — InvoiceNow
Checked 7 October 2026. Rules change — confirm what applies to your business with the official source.
FAQ
Common questions.
What is InvoiceNow?
InvoiceNow is Singapore's nationwide e-invoicing network, run by IMDA (Infocomm Media Development Authority) on the open Peppol standard. Invoices travel directly between businesses' finance systems as structured data — no PDFs, no re-typing.
What is the GST InvoiceNow requirement?
Under IRAS's GST InvoiceNow requirement, GST-registered businesses send their invoice data to IRAS (Inland Revenue Authority of Singapore) through InvoiceNow, using an InvoiceNow-ready solution connected to an IMDA-accredited Access Point. It is being phased in from November 2025, reaching every GST-registered business by April 2031.
When does my business need to comply with GST InvoiceNow?
It depends on how and when you registered for GST. 1 Nov 2025: Newly incorporated companies registering for GST voluntarily within 6 months of incorporation. 1 Apr 2026: Every new voluntary GST registration. 1 Apr 2028: New compulsory GST registrants, and existing GST-registered businesses with total annual supplies of S$200,000 or less. 1 Apr 2029: Existing GST-registered businesses with total annual supplies of S$1 million or less. 1 Apr 2030: Existing GST-registered businesses with total annual supplies of S$4 million or less. 1 Apr 2031: All remaining GST-registered businesses (annual supplies above S$4 million). Check iras.gov.sg for the rules that apply to you.
What is a Peppol Access Point?
An IMDA-accredited gateway that sends and receives documents on the InvoiceNow network for you. HeyInvoice runs on SESAMi, an IMDA-accredited Access Point.
What is an InvoiceNow-Ready Solution Provider (IRSP)?
IMDA's accreditation for software connected to InvoiceNow through an accredited Access Point that supports the GST InvoiceNow requirement. HeyInvoice's IRSP accreditation is in progress.
Is InvoiceNow the same as Peppol?
InvoiceNow is Singapore's name for its national e-invoicing network, which runs on the international Peppol standard. A Singapore business on InvoiceNow can exchange e-invoices with Peppol users in other countries.
Can I still email PDF invoices?
A PDF emailed to a customer is not an InvoiceNow e-invoice. Once the GST InvoiceNow requirement applies to you, invoice data has to reach IRAS through InvoiceNow, so your invoicing needs to run through an InvoiceNow-ready solution.
How does HeyInvoice help with InvoiceNow?
HeyInvoice sends and receives e-invoices, credit notes and purchase orders over InvoiceNow through SESAMi, an IMDA-accredited Access Point, and transmits invoice data to IRAS once GST InvoiceNow submission is switched on. It connects to your accounting system or ERP through its API. HeyInvoice's own IMDA IRSP accreditation is in progress.