InvoiceNow Mandate for GST Businesses Singapore: Key Dates & What SMEs Must Do

Running a business in Singapore is already tough with rising costs, manpower gaps, and admin work stacking up. Now, GST-registered firms have another firm shift coming: InvoiceNow will no longer be optional.
If you’re still relying on emailed PDFs or the classic printed invoice, it’s time to rethink your workflow.

From Jurong East to Bedok, small businesses have been asking the same question over kopi: “Do I really need to switch?” The short answer? Yes — and the deadlines are real.

Before we go deeper, here’s a quick comparison to help you see why this shift is happening.

InvoiceNow vs Traditional PDF Billing

Feature	PDF / Email Invoice	InvoiceNow (Peppol Network)
Data Entry	Manual typing required	Auto-synced into accounting system
Error Risk	High (human mistakes)	Low (machine-to-machine)
Payment Speed	Often delayed	Typically faster
Compliance with IRAS	Becoming outdated	Future standard
Cost	Higher admin time	Usually included or low-cost

What Is InvoiceNow & Why PDF Isn’t Considered E-Invoicing

Many SMEs assume emailing a PDF counts as “digital invoicing.” But IMDA has clarified repeatedly — a PDF is not an e-invoice.

InvoiceNow uses the Peppol network, which sends invoice data directly between accounting systems, almost like two machines talking without any human touching the numbers.
You could be on Xero and your client could be on SAP — InvoiceNow still connects instantly.

Think of it as the Singpass of invoicing: one standard that works everywhere.

The Mandatory Timeline Every GST Business Must Know

Let’s break it down clearly because this is where most business owners get confused.

1 May 2025 — Soft Launch (Voluntary)

You can start early, and honestly, many firms already have. Early adopters usually get smoother transitions and may enjoy support schemes.

1 November 2025 — New Voluntary GST Registrants

If you apply for GST registration on or after this date, you must use InvoiceNow for B2B transactions.

1 April 2026 — All New GST Registrants

Whether voluntary or compulsory, every new GST-registered business must transmit invoices through InvoiceNow.

What About Existing GST-Registered Businesses?

IRAS hasn’t enforced a hard deadline yet, but the writing is on the wall.
Eventually, all GST-registered companies will be expected to send invoice data through InvoiceNow so IRAS can process tax administration more efficiently.

Why The Government Is Enforcing This

Let’s be honest — SMEs already feel weighed down by compliance tasks. But this shift isn’t just red tape.

Here’s what’s really behind it:

1. GST Fraud Prevention

InvoiceNow helps IRAS detect suspicious patterns instantly, cutting down “carousel fraud” and false GST claims.

2. Faster Payments for SMEs

No more “Sorry, your invoice went to spam.”
Buyers receive the invoice directly inside their system, which speeds up approvals.

3. Lower Operating Costs

A paper invoice can cost $10–$20 in admin time.
InvoiceNow cuts that to almost nothing.

How to Set Up InvoiceNow Without Spending Big

The fear most owners have? “Wah, must buy expensive software again ah?”
Good news — you don’t.

Option A: Free Solutions (Good for Micro-SMEs)

If you’re only sending a few invoices a month, you can use IMDA-approved free portals.

Steps:

1. Go to IMDA’s Pre-Approved Solutions page.
2. Look for providers offering free tiers (e.g., Datapost, LinkFor — check latest list).
3. Verify your UEN using CorpPass.

Option B: Use Your Existing Accounting Software

If you’re using Xero, QuickBooks, ABSS, Deskera, chances are the feature is already included.

Setup usually takes under 10 minutes:

• Open accounting software
• Find “E-invoicing” or “Peppol” settings
• Register using CorpPass
• Receive your Peppol ID

Option C: PSG Support for Software Upgrades

If you need to upgrade your accounting tools, the Productivity Solutions Grant (PSG) may subsidise up to 50% of costs.

What Happens If You Ignore the Mandate

This part has been stressing many owners out, so let’s break it down calmly.

1. Possible GST De-Registration

From 1 Nov 2025, if you register for GST but don’t use InvoiceNow, the Comptroller of GST can cancel your registration.

And if your turnover is above $1 million, operating unregistered is illegal.

2. Penalties Under the GST Act

Failing to keep proper digital records can lead to:

• Fines up to $5,000
• Up to 6 months imprisonment
• Or both

IRAS may also deny your input tax claims if they cannot verify your invoices.

3. Higher Audit Risk

Firms refusing to digitise tend to get flagged for audits because their records are harder to verify.

Simple Action Checklist for SME Owners

You don’t need to overhaul your business — just follow this:

1. Check Your Software

Ask your vendor: “Are we Peppol-ready?”

2. Register for Your Peppol ID

Takes 10 minutes with CorpPass.

3. Send a Test Invoice

Try sending a $1 invoice to a supplier who’s already on InvoiceNow.

4. Collect Peppol IDs From Customers

Add these IDs into your system now for smooth future billing.

Final Thoughts

The shift to InvoiceNow isn’t about making life tough for SMEs. It’s about preparing Singapore’s business ecosystem for a fully digital economy.
Yes, the transition may feel troublesome for businesses used to PDFs and stamps. But once you get the hang of it, the cost savings and faster payments are worth it.