For all GST-registered businesses in Singapore, filing and paying GST returns on time is a core compliance requirement. GST returns allow companies to report the output tax collected on sales and the input tax paid on purchases, and to settle the net GST due with the Inland Revenue Authority of Singapore (IRAS) on a regular basis. Timely and accurate filing helps avoid penalties, administrative actions, and cash-flow complications.

Who Must File GST Returns

Any business that is GST-registered in Singapore must file GST returns for each accounting period, whether registration is compulsory (exceeding the S$1 million turnover threshold) or voluntary. Even if the business did not make any transactions during a period, a nil return must be filed to remain compliant.

Filing Frequency and Deadlines

Quarterly Filing (Standard Practice)

Most GST-registered businesses use quarterly accounting periods. Under current IRAS rules:

• GST returns and payments are due one month after the end of each accounting period.

For example:

• A quarter that ends on 31 March requires filing and payment by 30 April
• A quarter that ends on 30 June requires filing and payment by 31 July

Special Accounting Periods

Some businesses operate on special accounting periods that do not align with calendar quarters. In such cases, the GST return and payment deadline is generally one month from the end of the special period, unless IRAS has approved a different arrangement.

If you wish to change your GST accounting period, you may apply to IRAS, subject to approval.

Consequences of Late Filing or Non-Filing

Failing to file or pay GST returns by the due date is considered an offense under Singapore tax law. IRAS can take several actions in response:

• • Late submission penalty
    • A flat penalty (e.g., S$200) is imposed when a return is filed late.
  • Continued lateness penalties 
    • Additional penalties may be added for each month the return remains outstanding, up to prescribed limits.
  • Estimated assessments
    • IRAS can issue estimated GST assessments based on available information and impose a late payment penalty on the estimated tax.
  • Enforcement action
    • Persistent non-compliance may lead to further recovery actions or court proceedings.

Need More Time to File GST? 

If you require additional time to file your GST return, IRAS allows businesses to apply for an extension, although approval is not guaranteed. Extension requests are assessed against specific, acceptable reasons, such as system issues or unforeseen circumstances that prevent timely filing.

Businesses should review IRAS’s list of approved reasons before submitting a request and ensure that any application is properly justified and made before the filing due date, as extensions are granted only in limited and exceptional situations.

Best Practices to Meet GST Deadlines

To ensure timely and accurate GST filing:

• • Mark key dates at the start of each accounting period so your team is aware of upcoming deadlines.
  • Prepare records early, including sales invoices, purchases, and tax invoices to support output and input tax figures.
  • Use accounting software that aligns with IRAS requirements and helps streamline GST calculations.
  • Review returns before submission to minimise errors that could delay processing or trigger audits.
  • File nil returns for periods with no activity. 

Final Thoughts

Understanding your GST return deadlines and how they are calculated is essential for maintaining compliance and avoiding costly penalties. Singapore’s IRAS provides clear timelines and tools to help businesses stay on track.

If you would like support with GST compliance, return preparation, or reviewing your internal processes, our team at Verti is always happy to help. Reach out to us at contactus@verti.sg or +65 6909 5691.

All information accurate as of 15 December 2025