InvoiceNow Singapore: Get Your Invoicing and ERP Ready for E-Invoicing

PDF invoices are not e-invoices

Emailing a PDF is not InvoiceNow. The network transmits structured invoice data machine-to-machine, and most homegrown invoicing tools cannot produce it.

Unclear what the GST timeline means for you

IRAS has begun phasing in GST InvoiceNow requirements, starting with new voluntary GST registrants, and has announced an extension to all GST-registered businesses in stages. Many owners are unsure when their business is affected.

Legacy invoicing cannot map to Peppol

Older systems store line items, GST treatment, and party details in formats that do not translate cleanly into the structured invoice format Peppol requires.

GST categories are inconsistent

Standard-rated, zero-rated, and exempt supplies are labelled differently across quotes, invoices, and accounting exports, which breaks validation.

Double entry between systems

Staff key the same invoice into the operations system, the accounting software, and sometimes a customer portal, so errors and delays multiply.

No status visibility after sending

Once an invoice leaves your system, nobody knows if it was delivered, rejected, or stuck, so finance chases payments blind.

A nationwide e-invoicing network

InvoiceNow is Singapore's national e-invoicing initiative, built on the international Peppol framework, that lets businesses send invoices as structured data directly between finance systems.

• Invoices move between systems, not inboxes
• Structured data rather than a PDF
• Receiver validates automatically

Built on Peppol

Peppol is an open standard for exchanging business documents. Your software produces the invoice in the required format, and accredited Access Point providers deliver it across the network.

• An international standard, not a local format
• Access points route the documents
• Your ERP maps its fields once

Why IRAS cares

IRAS has begun phasing in the use of InvoiceNow for GST-registered businesses, starting with new voluntary GST registrants, so invoice data can be transmitted in a structured, consistent way. Check the latest IRAS announcements for the requirements and dates that apply to your registration.

• Structured data is machine-checkable
• Reduces manual GST reporting error
• Direction of travel for SG business

What InvoiceNow-ready means

Your invoicing or ERP software can generate compliant structured invoices, validate them, and hand them to an accredited Access Point for transmission, without staff re-keying data.

• You can emit a compliant structured invoice
• Your GST categories map correctly
• Delivery status is visible after sending

What it is not

Emailing PDFs, sharing spreadsheets, or using a portal to retype invoices is not e-invoicing. The value comes from system-to-system structured data.

• Not simply emailing a PDF
• Not a replacement for your accounting system
• Not automatic just because you have an ERP

Where Digital 9 Labs fits

We are a software builder, not an Access Point. We have built an e-invoicing web app with InvoiceNow-ready workflows, and we design invoicing and ERP systems that connect to accredited providers for transmission.

• We map your existing invoices to the format
• We connect the access point
• You keep raising invoices the way you do

Mapping your fields

Your invoice already has the data. The work is mapping it to the standard: party identifiers, tax categories, line descriptions and totals.

• Party IDs mapped to the register
• Tax categories mapped per line
• Descriptions standardised once

Cleaning GST categories

Most legacy invoicing has drifted: zero-rated, exempt and standard-rated applied inconsistently across similar items.

• Audit the categories you actually use
• Correct the ones applied by habit
• Lock them to the product record

Connecting the access point

Transmission runs through an access point. Connecting it is a configuration exercise, not a rebuild.

• One connection, then it routes
• Test transmissions before go-live
• Delivery status returned to you

The volume argument

At 300 invoices a month, even two minutes each of manual handling is 10 hours a month, or about S$4,800 a year at a loaded S$40 an hour.

• 300 x 2 minutes = 10 hours a month
• Roughly S$4,800 a year
• Before any error correction

What does not change

You keep raising invoices the way your team already does. The structured document is emitted from what you already enter.

• Same screen, same workflow
• PDF still available for customers who want it
• No parallel invoicing process

What to confirm

Timelines and obligations are set by IRAS and evolve. Confirm your own dates and scope with IRAS or your tax adviser rather than relying on a vendor page.

• Check your GST registration status
• Check the applicable phase for your business
• Re-check before committing to a date

Confirm your own position

Obligations depend on GST registration status and the applicable phase. Confirm yours rather than relying on a vendor summary.

• Check GST registration status
• Check which phase applies to you
• Re-confirm before committing to a date

Audit your GST categories

Most legacy invoicing has drifted across standard-rated, zero-rated and exempt. Fix this before mapping anything.

• List the categories actually in use
• Correct the ones applied by habit
• Lock them to the product record

Standardise party identifiers

Structured invoices need the receiver identified correctly. Cleaning your customer register is usually the longest task.

• UEN captured for business customers
• Duplicates merged before mapping
• Register cleaned once, then maintained

Map the fields once

Your invoice already holds the data: line description, quantity, unit price, tax category and totals. Mapping is configuration, not a rebuild.

• Roughly 15 to 20 fields to map
• Mapped once, reused every invoice
• Validated before first transmission

Test before you switch

Send test documents through the access point and confirm they validate before anything customer-facing changes.

• Test transmissions first
• Confirm validation passes
• Keep PDF fallback during transition

Count the manual handling you remove

At 300 invoices a month and two minutes of handling each, that is 10 hours a month, or roughly S$4,800 a year at a loaded S$40 an hour.

• 300 x 2 minutes = 10 hours a month
• Roughly S$4,800 a year
• Before any error correction

Phase one, the proving module

Budget S$3,500 to S$12,000 for one workflow solved end to end, live in 4 to 8 weeks on a fixed quote.

• S$3,500 entry, fixed after review
• 4 to 8 weeks to live
• One workflow, fully solved

Phase two, the department

Once phase one is in daily use, a departmental build covering 3 to 4 linked workflows typically runs S$25,000 to S$60,000.

• 3 to 4 linked workflows
• S$25,000 to S$60,000 typical
• Scoped from evidence, not a wish list

Phase three, the operation

Sales, stock, finance, approvals and reporting together is a six-figure programme and should run across 12 to 18 months, not one quarter.

• 12 to 18 months, phased
• Each phase funds the next
• No single big-bang go-live

Internal time to reserve

Budget 8 to 15 hours of your own team's time per module for interviews, testing and training. This is the line most plans omit.

• 8 to 15 hours per module
• Spread across 6 to 8 weeks
• Mostly the person who does the work

Running cost after go-live

Hosting for an SME system commonly runs S$50 to S$300 a month billed at cost to your own account, plus optional care quoted by scale.

• S$600 to S$3,600 a year hosting
• Billed to you at cost
• Care optional, quoted by scale

The comparison to run

Against a 20-seat licence at S$120 a month, five years is S$144,000 before implementation. Run both numbers over 5 years before deciding.

• 20 x S$120 x 12 = S$28,800 a year
• S$144,000 over 5 years, licence only
• Compare 5-year totals, not monthly

Grant treatment

EDG can support up to 50% of qualifying costs for eligible local SMEs on a custom build, on reimbursement, and the project must not start before applying. PSG does not cover custom work.

• Up to 50% of qualifying cost
• Reimbursement, not upfront
• Apply before starting
• Confirm with Enterprise Singapore

ERP

Enterprise resource planning: one system holding the records that several departments share, so a customer, job or stock item exists once rather than in five files.

• One record, many departments
• Replaces reconciliation with a shared source
• Scope is a choice, not all-or-nothing

Module

A functional area such as quoting, stock or payroll. A custom build means choosing three or four rather than buying twelve.

• Buy or build only what you use
• Modules share one data model
• Added when the last one is adopted

Master data

The reference records everything else points at: customers, suppliers, products, staff, cost codes.

• Cleaned once, maintained forever
• Duplicates here corrupt every report
• Owned by a named person

Transactional data

The events: quotes, orders, receipts, invoices, payments, timesheets. Volume grows daily; master data does not.

• Grows with trading volume
• Immutable once posted
• Corrections by reversal, not edit

Source of truth

The system everyone agrees to believe when two numbers disagree. Naming it is a management decision, not a technical one.

• Named explicitly, in writing
• Other systems reconcile to it
• Ambiguity here causes most disputes

Integration

A connection letting two systems exchange records automatically instead of by export and import.

• API or scheduled file exchange
• Direction matters: push, pull or both
• Failure handling is the hard part

API

An interface letting software talk to software. If a vendor has none, every future connection is manual.

• Ask before you buy
• REST is the common standard
• Rate limits and auth are the details

Audit trail

The record of who changed what and when. The difference between an explanation and an argument.

• Every change attributed
• Retained, not overwritten
• Required for most audits

Role-based access

Permissions granted by job function rather than by trust, so leavers are offboarded in one action.

• Permission by role, not person
• Sensitive screens hidden
• Revoked centrally

Cost code

The label that puts a cost against the job, department or project it belongs to.

• Applied at purchase, not month end
• Drives job profitability
• Kept short and stable

Committed cost

Money promised but not yet invoiced, usually at purchase order. The figure spreadsheets almost never capture.

• Visible at PO, not at invoice
• Early warning on overruns
• Distinct from actual cost

Reconciliation

Checking two records agree. Most of it exists because data was entered twice.

• Symptom of duplicate entry
• Removed by integration
• Never fully eliminated

Data migration

Moving existing records into the new system, usually the longest and least glamorous task.

• Cleaning is the larger half
• Archive rather than import everything
• Agree a cutoff date

Parallel run

Operating old and new together for one cycle so outputs can be compared before switching.

• One full cycle minimum
• Compare, do not assume
• Rollback stays available

Go-live

The point the new system becomes the record. Best done one module at a time.

• Never on a Friday
• One module, not twelve
• Support present for week one

User acceptance testing

The client testing that the system does what was agreed, using real scenarios rather than a script.

• Real cases, not happy paths
• Done by the people who will use it
• Sign-off before go-live

Change request

Work outside the agreed scope. Named and priced openly so it does not become an argument.

• Written, not verbal
• Priced before it is built
• Scope baseline retained

Technical debt

Shortcuts that make the next change slower. Sometimes worth taking deliberately, never worth taking silently.

• Recorded when taken
• Repaid before it compounds
• Invisible debt is the dangerous kind

Uptime

The share of time the system is available. Ask what it is measured against and who reports it.

• Measured, not promised
• Excludes planned maintenance
• Meaningless without monitoring

Backup and restore

Copies of your data, and the tested ability to bring them back. Only the second one matters.

• Automated and frequent
• Restore actually tested
• Recovery time measured

SSO

Single sign-on: one login across systems, so access is granted and revoked in one place.

• Central control of access
• Faster offboarding
• Fewer shared passwords

Two-factor authentication

A second proof of identity beyond the password. The cheapest security improvement available.

• Enabled for all admin users
• App-based beats SMS
• Recovery codes stored safely

PDPA

Singapore's Personal Data Protection Act, governing how personal data is collected, used and kept.

• Applies to staff and customer data
• Consent and purpose matter
• Breach obligations exist

GST

Goods and services tax, applied per line with the correct category. Errors here are a filing problem.

• Category per product, not per invoice
• Tax invoice timing matters
• Credit notes must reverse cleanly

Peppol

The international network standard behind structured e-invoicing, used by InvoiceNow in Singapore.

• Documents routed, not emailed
• Validated before acceptance
• Each participant has an identifier

CPF

Central Provident Fund: statutory contributions varying by age band and residency status.

• Rates change; confirm with CPF Board
• PR rates step up over two years
• Computed by the payroll run

SDL

Skills Development Levy, payable on top of CPF and computed in the same run.

• Applies alongside CPF
• Part of the payroll computation
• Not an optional extra

EDG

Enterprise Development Grant: supports up to 50% of qualifying costs for eligible local SMEs, on reimbursement.

• Custom builds may qualify
• Apply before the project starts
• Confirm with Enterprise Singapore

PSG

Productivity Solutions Grant, which funds pre-approved packaged solutions rather than custom work.

• Packaged solutions only
• Custom builds do not qualify
• Check the approved list first

SaaS

Software as a service: rented software, priced per user per month, hosted by the vendor.

• Recurring, not one-off
• Cost scales with headcount
• Vendor owns the roadmap

On-premise

Software running on a server you own and maintain, with the costs and control that implies.

• Hardware refresh every 4 to 5 years
• You own patching and backups
• Full control of the data

Total cost of ownership

Licence plus implementation plus migration plus training plus upgrades, over five years rather than one.

• Five years, not monthly
• Include internal time
• The only fair comparison

Vendor lock-in

The cost of leaving. Measured by whether you can export your data and who owns the code.

• Ask about export before buying
• Code ownership in writing
• Proprietary formats are the trap

Scalability

Whether the system copes as volume grows, and what it costs when it does.

• Load versus headcount pricing
• Test at 3x current volume
• Ask what breaks first

Workflow

The sequence of steps and approvals a piece of work passes through, and who owns each.

• Mapped before it is built
• Handoffs are where cost hides
• Encoded once, applied always

Approval threshold

The value above which something needs a second person to agree. Enforced by the system rather than by habit.

• Set by role and by value
• Auditable
• Prevents surprise discounts

Dashboard

A live view of the numbers management asks for, computed from records rather than assembled monthly.

• Live, not monthly
• Same data the team uses
• Few numbers, chosen deliberately

Reporting period

The window a report covers. Agreeing it prevents two people producing different truths.

• Defined and consistent
• Cutoff time stated
• Comparable period on period

Prerendering

Serving fully-formed HTML so crawlers and AI assistants read the content without running JavaScript.

• Content visible without JS
• Faster first paint
• Essential for search visibility

Agentic automation

Software that acts on records rather than only reporting on them, with human approval on anything consequential.

• Acts, not just reports
• Approval gates on money and messages
• Only as good as the data

Ask for the five-year total

Licence times sixty months plus implementation, migration and training. One number, comparable across vendors.

• 60 months, not one
• All one-off costs included
• Written, not verbal

Ask who owns the code

This single answer determines whether you can ever leave.

• Ownership in writing
• Repository access
• Another developer could take over

Ask about data export

A system you cannot export from is a system you cannot leave.

• Full export on demand
• Readable formats
• Scheduled exports you control

Ask what happens in week one

A vendor who starts with observation is scoping from your problem, not their product.

• Who they interview
• Whether they walk a real job
• What they hand back

Ask what they will refuse to build

A vendor who says yes to everything has not understood the problem.

• Where they recommend off-the-shelf
• What they push back on
• Out of scope on principle

Ask to see it running

Screenshots are not a system. Ask for a populated live environment.

• Live, not slides
• Populated, not empty states
• Someone using it

Ask about the second module

The first is a project; the second tests whether the architecture extends.

• Shared data model
• What clients added later
• How long it took

Ask for the support commitment in hours

Response time in hours, business days defined, escalation path named.

• Hours, not adjectives
• Business days defined
• Named escalation

Ask who maintains statutory logic

CPF, GST and e-invoicing rules change. Someone must own keeping them current.

• Named owner
• In the contract
• Update mechanism stated

Ask about the parallel run

One full cycle with both systems live is what turns confidence into evidence.

• One cycle minimum
• Outputs compared
• Rollback available

Ask what training is included

Two to five days by role, with a follow-up after real use begins.

• Days stated
• Per role
• Follow-up included

Ask how change requests are priced

Scope will change. How that is handled is worth agreeing before it happens.

• Priced openly
• Baseline retained
• Written approval

Ask for a reference you choose

Not the reference they offer. One you pick from their portfolio.

• You pick, not them
• Same size and sector
• Ask what went wrong

Ask what the system will not do

Every system has limits. A vendor who names them is a vendor who understands theirs.

• Named limits
• Workarounds explained
• No magic claims

Ask about hosting and who is billed

Hosting billed at cost to your account avoids a reseller margin you cannot see.

• Billed to you at cost
• Your account, your access
• No hidden margin

Do we have to replace everything at once

No, and you should not. One module, adopted, beats four half-built. Everything else keeps running.

• One workflow first
• Existing tools stay
• Integrate rather than replace

What if we outgrow it

A build extends at the cost of the work. That is the argument for owning the code rather than renting seats.

• Extended, not replaced
• Your priority order
• No tier upgrade pricing

How do you handle our data

It stays in a database you own, in a region you choose, exportable in full at any time.

• Your database, your region
• Full export on demand
• Access documented and auditable

What if the project stalls

Fixed scope, fixed quote and weekly working builds mean a stall is visible in week three, not month six.

• Weekly working build
• Visible early
• Fixed scope baseline

Can our own developer take it over

Yes. Standard stack, documented handover, and the repository is yours.

• Standard technologies
• Handover documentation
• Repository ownership

What ongoing cost should we budget

Hosting at cost plus optional care quoted by scale. No per-seat component at all.

• Hosting S$600 to S$3,600 a year
• Care optional
• No per-seat fee

How do you price changes after go-live

Openly, against the written scope baseline, with approval before anything is built.

• Priced before built
• Baseline retained
• Written approval

What happens if we stop working with you

You keep the code, the data and the hosting accounts. That is the point of ownership.

• Code and data yours
• Hosting on your accounts
• Another developer can continue

Do you work with our existing accountant

Yes, and we usually ask to. They know where the numbers have to land.

• Accountant involved early
• Statutory treatment confirmed
• Reports built to their format

How do we measure whether it worked

Against the hours you measured before we started. That is why we measure them in week one.

• Baseline measured first
• Same measure after
• Module two argued from it