What this March 2026 edition covers
The second edition, dated 9 March 2026, explains the GST InvoiceNow requirement across 85 PDF pages. Certain requirements identified in paragraphs 3.2, 3.3 and 3.5 have force of law. The guide distinguishes the conditions for voluntary GST registration already being implemented from the legislative changes then planned for later phases. Read later IRAS updates alongside this dated edition; examples and proposed implementation details are not a substitute for a subsequent clarification.
InvoiceNow, Peppol and the IRAS data connection
InvoiceNow uses structured electronic invoices transmitted through the Peppol network. An InvoiceNow-Ready Solution Provider (IRSP) supplies compatible software; an accredited Access Point (AP) connects it to the network. An invoice exchanged between supplier and customer follows the four-corner model, with IRAS receiving required tax data as the fifth corner. PINT-SG, introduced in February 2024, provides the Singapore invoice specification. An emailed PDF is not itself a structured InvoiceNow submission. Peppol identification, UEN registration and network discovery are separate from deciding the tax treatment of the transaction.
The six implementation phases
For covered voluntary applicants, compliance is a registration condition and non-compliance can lead to revocation. The first two phases depend on the application and the effective registration arrangements. The later phases were announced in this edition with further legislative implementation to follow. A Singapore branch of a foreign company is not excluded merely because the head office is overseas.
| Phase start | Businesses covered |
|---|---|
| 1 November 2025 | Newly incorporated companies applying for voluntary registration within six months of incorporation |
| 1 April 2026 | All new voluntary GST registrants, irrespective of business structure or incorporation age |
| 1 April 2028 | New compulsory registrants and existing registrants with annual supplies of S$200,000 or less |
| 1 April 2029 | Existing registrants with annual supplies above S$200,000 and up to S$1 million |
| 1 April 2030 | Existing registrants with annual supplies above S$1 million and up to S$4 million |
| 1 April 2031 | Remaining existing registrants with annual supplies above S$4 million |
How existing businesses determine their phase
Use annual total supplies reported in Box 4, comprising Boxes 1, 2 and 3, for GST accounting periods ending in calendar year 2025. A non-calendar year-end does not mean using only January to December transactions. The guide gives quarterly totals of S$100,000, S$800,000 and S$2 million leading respectively to April 2028, 2029 and 2030. Annualise a registration period shorter than a year: registration on 7 February 2025 with S$1.5 million over 328 days becomes S$1,669,207 using 365/328, placing the business in April 2030. Examples 1–3 distinguish a newly incorporated November 2025 voluntary applicant, an older April 2026 voluntary applicant and an April 2028 compulsory applicant.
Excluded overseas and reverse-charge businesses
The exclusions cover specified overseas businesses, including relevant Overseas Vendor Registration and section 33(1) arrangements, and businesses registered solely because of reverse charge on imported services or low-value goods. A locally incorporated business with an overseas branch remains within the ordinary rules. Reverse-charge registration alone does not give a permanent exclusion if ordinary taxable supplies later exceed the normal registration threshold.
Annex D: test reverse-charge exclusions separately
For a new applicant, compare imported services/LVG and ordinary taxable supplies separately. Example 29 treats S$1.1 million of imports with S$10,000 of local sales as excluded, but S$1.2 million of imports with S$1.3 million of local sales as not excluded. Prospectively, S$1.5 million of imports and S$20,000 of local sales are excluded; S$1.9 million and S$1.8 million are not. Existing excluded businesses must monitor other taxable supplies. Exceeding S$1 million retrospectively at calendar year-end or prospectively triggers notification to IRAS within 30 days and onboarding. Example 30 gives 30 January 2032 for liability on 31 December 2031 and 19 October 2032 for liability on 19 September 2032. Reverse-charge supplies are not added to the ordinary supplies test to defeat the exclusion.
Four routes for transmitting sales and purchases
Type 1A covers a supplier’s invoice sent through InvoiceNow, with data transmitted through its AP. Type 1B covers a buyer’s data extracted from an InvoiceNow invoice into its purchase records. Type 2 covers sales invoiced outside the network; Type 3 covers purchases received outside it. Credit notes follow the corresponding routes. A successful commercial invoice exchange and a successful IRAS tax-data submission are separate operational events, so monitor acknowledgements and rejected transmissions.
Sales and purchases that must be transmitted
The scope covers reportable standard-rated, zero-rated and relevant exempt sales, and applicable standard-rated or zero-rated purchases. It also covers invoices under special schemes: underlying goods handled in ACMT rather than disregarded overseas processing charges, AMFT and GMS transactions, discounted-price sales, customer accounting and marketplaces’ underlying OVR supplies. Relevant exempt non-financial transactions, including residential property and investment precious metals, are included. Do not decide scope merely from whether GST appears on the invoice.
Transactions outside the mandatory scope
The exclusions include deemed supplies, reverse-charge output, exports without an actual sale, exempt financial services and digital payment token supplies even where zero-rated, import permits and reverse-charge purchase records. Purchases from an overseas head office or branch, non-GST-registered suppliers, blocked expenses, exempt purchases and relevant out-of-scope transactions are also outside mandatory transmission. Other examples include regulatory fees, qualifying transfers of a business as a going concern, carbon credits and third-country sales. Annex E accepts more codes than the mandatory scope requires: optional transmission is possible with software/AP support.
Mixed invoices and partially business purchases
If an invoice has at least one in-scope line, transmit the whole invoice, including its out-of-scope lines. Example 8 includes rent and a refundable deposit on one invoice. For a S$7,000 phone purchase with S$630 GST and business use of four-sevenths, Example 9 allows S$4,000 plus S$360 GST for the business portion or the full S$7,000 plus S$630, provided the adopted approach is consistent. Transmission does not by itself make the full input tax deductible.
Permitted aggregation and batch limits
Aggregation is restricted to qualifying point-of-sale (POS) sales, simplified tax invoice (STI) sales and petty cash purchases (PCP). POS takes precedence if both POS and STI descriptions apply. Daily POS and weekly employee-claim aggregates are illustrated; ordinary invoices are not freely aggregated. For POS/STI, use the specified customer defaults in the customer name, UEN, endpoint and address fields; PCP uses the prescribed supplier defaults including supplier GST number. Bulk submission is limited to ten documents of the same type and 10 MB.
Submission deadlines and transaction dates
Submit no later than the earlier of the actual GST return filing date and the statutory filing deadline for the relevant accounting period. Supply transaction dates generally follow the issued invoice, or the accounting posting where there is no invoice. Purchases use invoice dates or the processing/posting basis adopted for the input claim. A 20 March invoice with a return actually filed on 20 April is due by 20 April, even if the statutory deadline is 30 April. Filing late on 15 May does not extend the 30 April data deadline.
Pre-registration, deregistration and advance payments
Pre-registration input claims are outside the data requirement although supporting records remain necessary. Example 14 excludes the pre-registration portion claimed in the first return. Examples 15–16 show a 20 June supply or purchase invoiced on 5 July after 1 July deregistration: the invoice is outside transmission scope even though final-return tax accounting may still arise. Do not manufacture a tax invoice merely to match an advance payment. Example 17 separates a 12 June 2031 pro forma/payment from the 10 July tax invoice; its July-period data deadline is 20 October where that is the actual filing date.
The mandatory data elements
Map document identity and currency, supplier/customer identity and addresses, line-level quantities and GST treatment, category subtotals and invoice totals. Software normally generates the customization/profile identifiers, scheme identifiers and document UUID. The supplier’s GST number and tax scheme must be correct; the buyer must be identified accurately. Entity customers use their UEN or relevant foreign registration number. For individuals, this edition describes using the individual’s name and NA where the prescribed identity/address details are unavailable, without collecting an NRIC simply to populate the XML. Follow the latest field specifications for implementation.
| Data group | Principal fields |
|---|---|
| Document | IBT-024 customization; 023 profile; 001 number; BT-SG-003 UUID; 002 date; 003 type; 005 currency |
| Supplier | IBT-034 endpoint; 034-1 scheme; 030 UEN; 031 GSTN; 031-1 tax scheme; 027 name; 035 address; 038 postcode; 040 country |
| Customer | IBT-049 endpoint; 049-1 scheme; 047 UEN; 044 name; 050 address; 053 postcode; 055 country |
| Lines | IBT-126 identifier; 153 item; 130 unit; 129 quantity; 146 net price; 131 net amount; 151 GST code; 152 rate; 167 tax scheme |
| Category totals | IBT-116 taxable amount; 117 tax; 118 code; 118-1 tax scheme; 119 rate |
| Document totals | IBT-106 net lines; 109 total excluding GST; 110 total GST; 112 total including GST; 115 amount due |
Validation, tax invoices and rejected records
The schema and Schematron rules validate required fields and arithmetic. Handle rounding differences consistently and investigate rejected records rather than assuming submission succeeded. GST registration checks through available APIs can help verify the supplier/customer status. A valid Peppol invoice need not display the words Tax Invoice if it otherwise satisfies regulation 11. For a solution-extracted submission, the underlying tax invoice must still meet the ordinary requirements; the XML data does not replace an invalid supporting document.
Credit notes issued and received
Submit issued credit notes even where the credit note does not adjust GST, using the proper category and conditions. Cancellation credits should match the cancelled invoice; record preceding invoice number/date in IBT-025/026 when known, and retain other linkage evidence when not available. For received credits, either record the original purchase and the credit separately or the net purchase if the original has not yet been processed. Examples 18–19 distinguish returned/defective work and a S$9,000 purchase reduced by S$1,000: net S$8,000 is possible before original processing; otherwise preserve the S$9,000 purchase and S$1,000 credit trail.
Correcting data and preserving document identity
A correction to an existing record is resubmitted using the same document UUID, so the latest submission replaces the previous one. A newly issued credit note has its own document identity and is not an overwrite of the invoice. Examples 20–22 cover address and item-description corrections and changing an incorrectly assigned TX code to ZP. This March edition discusses buyer handling of an unprocessed original/revised invoice; later FAQ instructions should be used to settle current resubmission practice. Keep the accounting change, source document and IRAS transmission aligned.
Foreign currency and mixed GST categories
Use an approved exchange-rate method for Singapore-dollar GST amounts. In Example 23, US$1,000 converts to S$1,350; US$90 GST equals S$121.50 and US$1,090 gross equals S$1,471.50. Transmit the required document-currency and SGD totals even though an exchange-rate field itself is not mandatory. Example 24 combines five S$20 hats and eight S$25 shirts at 9%, with ten S$40 shoes at 0%: standard-rated subtotal S$300/GST S$27, zero-rated subtotal S$400, net total S$700 and gross/amount due S$727. Do not assign one tax category to the whole mixed invoice.
Which entity identifiers to use
For a company, use the company’s sender and supplier UEN even where it owns sole proprietorship businesses. Partnerships use the invoicing partnership’s UEN and the relevant partnership GST number. Sole proprietors use the business UEN where available, otherwise the prescribed GST-number arrangement. GST groups use the sending member’s UEN, supplying member’s UEN and group GST number. Divisional registration uses the parent UEN and division GST number. Section 33(2) agent arrangements use the agent’s prescribed UEN/GST identifiers. Do not substitute the group representative’s identity indiscriminately for every supplier.
Discounted sales, GMS and AMFT schemes
Under the Discounted Sales Price Scheme, the invoice note should identify the scheme and software must accommodate tax calculated on the permitted basis. Under the Gross Margin Scheme, do not display GST as a separately claimable amount: supplier uses NA/0 and buyer TXNA/0 with an identifying note. AMFT similarly uses the required NA/0 and TXNA/0 entries with the prescribed payment-of-GST explanation. Transmission does not remove the special invoicing and return rules in each scheme’s own guide.
Self-billing and customer accounting
Self-billing requires the approved arrangement and prescribed buyer-created invoice wording; supplier and customer identities must remain in their correct roles. Example 25 shows both parties’ UEN/GST fields: the buyer submits purchase Type 3/TX, and supplier sales Type 2/SR, with records traceable even when the seller uses a different internal receivable number. For customer accounting, the supplier uses SRCA-S with rate 0 and the buyer’s GST number; the buyer uses TXCA at 9%. Example 26 for S$10,500 of memory modules shows supplier GST zero and total S$10,500, while the buyer accounts for S$945 tax and S$11,445 including the accounted GST. The different totals are intentional scheme treatment.
Groups, divisions and partial exemption
This edition flags separate arrangements for the joining date of members in GST groups or divisions; Example 27 illustrates a new voluntary member joining an existing group and refers to further communication. Do not infer an unconditional exemption from that example. For partially exempt businesses, transmit relevant purchases using the attribution code at processing, including taxable, regulation 33, non-regulation 33 and residual categories. Subsequent longer-period input adjustments generally do not require retroactive rewriting of invoice data. Example 28 distinguishes legal underwriting costs attributable to non-regulation 33 exempt supplies. This special attribution treatment must be considered alongside the general exclusions for purchases on which no input is claimed.
Reconcile returns without forcing artificial matches
Invoice data and GST returns need not match exactly because of payment-based time-of-supply rules, deemed supplies, reverse charge, apportionment, pre-registration input claims and later return adjustments. An F7 correction does not mean every original invoice must be overwritten. Maintain a reconciliation explaining the differences and the correct return treatment. Mere mismatch is not, by itself, a penalty trigger or permission to change valid underlying invoices.
Records, interruptions and implementation preparation
Retain XML and underlying source records for at least five years under the applicable record-keeping rules. During AP/API or system failure, activate a continuity plan, retain failed submissions and retry after recovery; commercial invoicing can continue independently of the IRAS connection. Extensions require IRAS consideration rather than arising automatically from a technical incident. Prepare by selecting a ready solution/AP, registering the Peppol/UEN identity and activating/testing IRAS submission. The guide warns that ERP projects may need three to twelve months. Use the AP’s specifications, APEX and the technical playbook for implementation details.
Annexes A and B: invoice and aggregation examples
The annexes compare network invoices with extracted sales/purchase records field by field. Invoice type 380 is illustrated with INV001 dated 30 November 2024: one laptop at S$1,945, GST S$175.05 and total S$2,120.05. The POS and employee-claim examples use one LOT aggregate of S$10,000, GST S$900 and total S$10,900, with POS/STI customer defaults or PCP supplier defaults. Customer endpoint formats differ between a network Peppol ID and the prescribed C5UID plus UEN format for extracted data. Customization/profile URNs are software-populated and differ for billing and payables. These are illustrative data, not genuine counterparties; the PCP text references January 2029 while its sample document date is November 2024, and a sample postcode is inconsistent. Do not copy those inconsistencies into live invoices.
Annex C: complete credit-note fields and an arithmetic warning
Issued and received credit-note examples use type 381, CN001, an explanatory note for a return against INV001, and the same identity, line, subtotal and total field families as an invoice. The supplier-side category is SR and the buyer-side line category TX. The illustrated speaker credit is S$500 with S$45 GST at 9%. The received-credit example correctly totals S$545.00; the issued-credit table prints S$545.50 for total and amount due, inconsistent with its own S$500/S$45 figures. This discrepancy is present in the rendered PDF, not an extraction artefact. Use the arithmetic-consistent S$545 calculation and validation rules rather than treating S$545.50 as a special tax rule. Sample repeated UUIDs do not authorise reusing an invoice UUID for a newly created credit note.
Annex E: all accepted supply codes
Acceptance of a code is not a finding that the transaction must be transmitted. NA is a permitted category code and also appears in the rate column to mean not applicable; it must not be confused with an ordinary 9% or 0% rate. Special-scheme software must allow tax amounts that do not equal 9% of the apparent standard-rated value. The non-registered business code NG does not create a GST registration or filing obligation.
| Code | Rate | Meaning |
|---|---|---|
| SR | 9% | Standard-rated goods/services |
| SRCA-S | NA | Supplier-side customer accounting |
| SRCA-C | 9% | Customer accounts for supplier’s GST |
| SRLVG | 9% | Own low-value goods supplies |
| NA | NA | Special-scheme treatment, including AMFT/A3PL/GMS/discounted-price basis |
| SRRC | 9% | Imported services/LVG under reverse charge |
| SROVR-RS | 9% | Marketplace accounts for third-party remote services |
| SROVR-LVG | 9% | Marketplace/redeliverer accounts for third-party LVG |
| DS | 9% | Deemed supplies |
| ZR | 0% | Zero-rated supplies |
| ES33 | NA | Regulation 33 exempt supplies |
| ESN33 | NA | Non-regulation 33 exempt supplies |
| OS | NA | Out-of-scope supplies |
| NG | NA | Supplies by non-GST-registered businesses |
Annex E: all accepted purchase codes
Attribution codes distinguish taxable, regulation 33 exempt, other exempt and residual input. Residual input covers expenditure benefiting taxable and exempt activities or the business generally. OP includes no-claim purchases such as non-business use, invalid tax invoices or a decision not to claim prudentially. NR covers both purchases from a non-registered supplier and purchases by a non-registered business. Import, reverse-charge, blocked and other non-reportable codes remain accepted for optional data but are not all mandatory invoice submissions.
| Code | Rate | Meaning |
|---|---|---|
| TX | 9% | Standard-rated taxable purchases |
| IM | 9% | Goods imports with GST paid to Customs |
| ME | 0% | MES/A3PL/other approved imports reportable in Box 9 |
| IGDS | 9% | Import GST Deferment Scheme imports |
| TXCA | 9% | Prescribed goods under customer accounting |
| TXNA | NA | Purchases under special schemes/bases |
| TXRC-TS | 9% | Reverse-charge imports attributable to taxable supplies |
| TX-ESS | 9% | Local purchases attributable to regulation 33 exempt supplies |
| TXRC-ESS | 9% | Reverse-charge imports attributable to regulation 33 exempt supplies |
| IM-ESS | 9% | Customs-taxed imports attributable to regulation 33 exempt supplies |
| TX-N33 | 9% | Local purchases attributable to non-regulation 33 exempt supplies |
| TXRC-N33 | 9% | Reverse-charge imports attributable to non-regulation 33 exempt supplies |
| IM-N33 | 9% | Customs-taxed imports attributable to non-regulation 33 exempt supplies |
| TX-RE | 9% | Residual local input for taxable/exempt supplies or general operations |
| TXRC-RE | 9% | Residual reverse-charge imports |
| IM-RE | 9% | Residual Customs-taxed imports |
| ZP | 0% | Zero-rated purchases |
| BL | 9% | Disallowed expenses |
| EP | NA | Exempt purchases |
| OP | NA | Out-of-scope purchases from registrants or input not claimed |
| NR | NA | Purchases from non-registrants or by non-registered businesses |
Official source
This article independently explains the substantive contents of the official PDF, including the relevant conditions, procedures and annexes. The linked document remains the authoritative source for its original wording, and later changes should be checked separately.
Read the official PDF ↗