Avoid IRAS Penalties: A Simple Guide to GST Filing in Singapore

Published on: 16 Oct, 2025

A Comprehensive Guide to Filing GST Returns in Singapore (Form F5)

Navigating the intricacies of tax compliance is a crucial aspect of running a successful business in Singapore. One of the key obligations for many companies is the Goods and Services Tax (GST). Understanding the deadlines and procedures for filing GST returns is essential to avoid penalties and ensure your business remains in good standing with the Inland Revenue Authority of Singapore (IRAS). This article provides a detailed guide to filing your GST returns, specifically focusing on Form F5.

Who Needs to File a GST Return?

In Singapore, any business registered for GST is required to file regular GST returns. GST registration is mandatory for businesses with a taxable turnover exceeding S$1 million in a 12-month period, or for those who anticipate their taxable turnover to exceed this amount. Businesses that do not meet this threshold may also voluntarily register for GST. Once registered, a business must charge GST on its supplies of goods and services and can, in turn, claim a refund for the GST it has paid on its own business purchases.

It is important to note that even if there is no business activity and no tax to be paid for a specific accounting period, a GST-registered business must still file a ‘nil’ return. Failure to do so can result in penalties.

Understanding GST Form F5

The primary document for reporting your GST transactions to IRAS is the GST Form F5. This form is an electronic return that must be submitted through the myTax Portal. The GST F5 provides a summary of your company’s sales, purchases, and the corresponding GST amounts for a specific accounting period.

The form includes several boxes where you will need to declare:

  • Total value of standard-rated supplies
  • Total value of zero-rated supplies
  • Total value of exempt supplies
  • Total value of taxable purchases
  • Output tax due (the GST you have collected from your customers)
  • Input tax and refunds claimed (the GST you have paid on your business purchases)

Accurate completion of this form is vital, as any errors could lead to delays in processing your return, requests for clarification from IRAS, or even an audit.

Deadlines for Filing GST Returns

GST returns must be filed quarterly, although some businesses may be approved for monthly filing. The deadline for filing your GST F5 return and paying any tax due is one month after the end of your accounting period.

The quarterly accounting periods are determined by your company’s financial year-end. For example:

  • For the accounting period of January to March, the filing deadline is 30th April.
  • For the accounting period of April to June, the filing deadline is 31st July.
  • For the accounting period of July to September, the filing deadline is 31st October.
  • For the accounting period of October to December, the filing deadline is 31st January of the following year.

Businesses that pay their GST through the GIRO scheme have an extended deadline for payment, typically until the 15th of the month following the filing deadline. However, the GST return itself must still be filed by the end of the month.

Step-by-Step Guide to Filing Your GST Return (Form F5)

Filing your GST return is a straightforward process when done through the myTax Portal. Here’s a step-by-step guide:

  1. Gather Your Documents: Before you begin, ensure you have all the necessary documents, including your sales invoices, purchase receipts, and records of all GST collected and paid during the accounting period.
  2. Calculate Your GST: Calculate your total output tax and the total input tax you are eligible to claim. Using accounting software can help streamline this process and minimize errors.
  3. Log in to myTax Portal: Access the myTax Portal using your company’s CorpPass credentials.
  4. Navigate to GST Filing: Once logged in, select the option to “File GST Return/Edit Past Return.”
  5. Complete GST Form F5: Enter the calculated figures into the respective boxes on the GST F5 form. Double-check all entries for accuracy. If you have no transactions to report, enter ‘0’ in all the required fields to file a nil return.
  6. Submit and Save Acknowledgment: After you have reviewed and confirmed the information, submit the return. Be sure to save a copy of the acknowledgment page as proof of your submission.

Navigating these compliance requirements can be complex. If you require assistance or tailored advice for your business, the experienced team at Raffles Corporate Services Pte Ltd is here to help.

Penalties for Non-Compliance

IRAS takes the timely and accurate filing of GST returns seriously. Failure to comply with the regulations can result in significant penalties:

  • Late Filing Penalty: A penalty of S10,000 per return.
  • Late Payment Penalty: A 5% penalty is levied on the unpaid tax. If the tax remains unpaid after 60 days, an additional 2% penalty per month will be imposed on the outstanding amount, up to a maximum of 50% of the tax outstanding.
  • Estimated Assessments: If you fail to file your return, IRAS may issue an estimated assessment of your tax liability, which you will be required to pay.

Conclusion

Filing GST returns is a non-negotiable responsibility for GST-registered businesses in Singapore. By understanding the requirements, adhering to the deadlines, and ensuring the accuracy of your GST Form F5, you can avoid unnecessary penalties and maintain a healthy relationship with the tax authorities. Staying organized with your record-keeping and utilizing the myTax Portal will make the process smoother and more efficient.

For further assistance or inquiries, you can contact the Raffles Corporate Services team via email at mailto:[email protected].

Yours sincerely,

The editorial team at Raffles Corporate Services