The Inland Revenue Authority of Singapore (IRAS) published the Sixth Edition of its GST: Time of Supply Rules e-Tax Guide on 18 August 2026.
The latest edition makes a limited technical update to the guide, revising footnotes 25 and 27 to reflect the renumbering of Regulations 16 and 20 under the Goods and Services Tax (General) Regulations.
The revision concerns statutory cross-references rather than a substantive change to the GST time of supply framework.
Key Update
1. Revision of Regulatory References
The Sixth Edition updates two footnotes to align the guide with the renumbered provisions of the GST (General) Regulations.
The changes are intended to ensure that references in the guide correspond with the current legislative numbering.
Based on the stated scope of the revision, there is no indication that IRAS has introduced new time of supply rules or changed the underlying GST treatment through this update.
2. Existing Time of Supply Principles Continue to Apply
The time of supply determines when a taxable supply is treated as taking place for GST purposes and, consequently, the accounting period in which output GST must generally be reported.
Under the general time of supply rules, the time of supply is ordinarily triggered by the earlier of:
- The issuance of an invoice; or
- The receipt of payment.
Special rules may apply to particular transactions and circumstances.
Businesses should continue applying the relevant statutory provisions and IRAS guidance when determining the correct GST accounting period.
Practical Implications
Although the latest revision is administrative in nature, businesses and tax professionals should ensure that their technical references remain current.
In particular:
- GST compliance manuals: Update references to the affected regulations where necessary.
- Accounting procedures: Continue applying the existing time of supply principles to determine the appropriate GST reporting period.
- Training materials: Ensure that references in internal GST guidance and staff training materials reflect the latest legislation.
- Tax reviews and advisory work: Refer to the Sixth Edition when preparing GST technical analyses and compliance documentation.
Recommended Action
GST-registered businesses do not need to change their existing time of supply accounting procedures solely because of this update. However, finance and tax teams should review their internal documentation and technical references to ensure consistency with the current GST (General) Regulations.
The Sixth Edition should be used as the current reference when interpreting and applying IRAS guidance on GST time of supply.
Technical Verification
IRAS’ e-Tax Guide listing confirms the publication date of 18 August 2026. The current GST legislation and IRAS guidance also confirm that the general time of supply rule remains based on the earlier of invoice issuance or receipt of payment, subject to applicable exceptions.
This article provides general technical information and does not constitute specific GST advice. The applicable time of supply depends on the transaction and relevant statutory provisions.
Source: IRAS, 18 August 2026