GST Time of Supply: When Liability Arises Under Sections 12, 13 and 14

Summary: Time of supply determines when GST liability arises and the tax period in which the liability must be discharged. Sections 12 and 13 of the CGST Act contain the principal rules for goods and services respectively, while Section 14 applies where there is a change in the rate of tax. The determination generally depends on statutory events involving invoices, receipt of payment, supply or prescribed time limits, with separate rules applying to reverse-charge transactions and continuous supplies. The concept also affects advances, invoicing, return reporting, applicable tax rates and potential interest liability. Businesses should therefore determine the nature of the supply, identify whether forward or reverse charge applies, examine invoice and payment dates, consider continuous-supply rules and separately apply Section 14 whenever there is a GST rate change.

When Does GST Liability Arise? The Legal Significance of Time of Supply

Introduction

GST is a destination-based indirect tax on supply of goods and services. However, the identification of a taxable supply does not answer the question: when does the liability to pay GST arise?

The answer is provided by the concept of “time of supply”. The time of supply provisions determine the point at which the liability to pay GST arises and consequently the tax period with respect to which the supplier is liable to discharge the tax. The provisions also have an important bearing on the rate of tax, invoicing, reporting and interest liabilities in case of delayed payment.

The principal framework is contained in Sections 12 and 13 of the Central Goods and Services Tax Act, 2017 (“CGST Act”) dealing respectively with time of supply of goods and services. Section 14 deals with determination of the time of supply where there has been a change in the rate of tax.

1. Meaning and Legal Significance of Time of Supply

“Time of supply” is essentially a mechanism for determining the point at which the liability to pay GST becomes due. It removes ambiguity by linking the tax liability to specific events such as issuance of an invoice, receipt of payment or completion of the prescribed period from the relevant supply.

This is particularly significant as GST is not determined by merely the date on which a commercial transaction is negotiated or agreement signed. The statutory rules determine what event fixes the tax point.

Having located the relevant time of supply, the supplier can identify the appropriate tax period during which the outward supply is to be reported and the corresponding tax discharged, subject to specific provisions and exceptions under the CGST Act.

2. Time of Supply of Goods — Section 12

For normal supply of goods where tax is payable under forward charge, the basic rule is set out in Section 12(2) of the CGST Act. The time of supply is the earlier of:

(a) the date of issue of invoice by the supplier, or the last date on which the supplier is required to issue the invoice; and

(b) the date on which the supplier receives the payment.

The framework, therefore, focuses attention on the timing of invoice and payment.

Example:

Suppose a supplier delivers goods on 5 October. The invoice is issued on 7 October and payment is received on 20 October. Assuming the invoice is issued within the prescribed period, the time of supply would ordinarily be 7 October as the invoice date precedes receipt of payment.

The rule must however be read in conjunction with special provisions applicable to supplies where the recipient is required to pay tax under reverse charge.

3. Time of Supply under Reverse Charge for Goods

Section 12 provides a separate mechanism for supplies of goods liable to tax under reverse charge. In such cases, the recipient rather than the supplier is responsible for paying GST.

The time of supply is determined by the statutory events specified in Section 12 including the date of receipt of goods, the date of payment as reflected in the recipient’s books or bank account and the date immediately following the prescribed period from the date of invoice, depending on the circumstances.

4. Time of Supply of Services — Section 13

The time of supply of services is primarily governed by Section 13 of the CGST Act.

In relation to services supplied under forward charge, Section 13(2) broadly applies the earlier-of-two-events principle but with a detailed structure in comparison to goods. Where an invoice is issued within the prescribed period, time of supply is generally the earlier of the invoice date or date of receipt of payment. Where the invoice is not issued within the prescribed period, the time of supply is generally linked to the date of provision of service or date of receipt of payment, as specified by the statute.

Example:

A consultant completes a service on 10 November and issues the invoice within the prescribed period on 15 November. If payment is received on 30 November, the time of supply will ordinarily be 15 November, subject to the statutory provisions applicable to the transaction.

5. Reverse Charge in Respect of Services

Section 13 also provides for special rules in relation to services on which GST is payable under reverse charge.

In such cases, the time of supply is determined with reference to the events specified by the CGST Act including the date of payment and the date following the prescribed period from the date of receipt of the invoice, as applicable.

6. Continuous Supply of Goods and Services

GST law also recognises the fact that certain supplies are completed through multiple events.

In the case of continuous supply of goods, specific rules are provided in Section 12 linked to successive statements of account or payments and other circumstances.

For continuous supply of services, rules are provided based on the due date for payment, issuance of invoices, performance of an event where payment is linked to such performance and other events as contemplated by the statute.

7. Change in Rate of Tax — Section 14

One of the most legally significant applications of the time-of-supply concept occurs where the rate of GST changes between the relevant dates.

Section 14 provides special rules for determining the time of supply where there is a change in the rate of tax. The analysis is based on the relationship between three events:

• supply of goods or services;
• issuance of the invoice; and
• receipt of payment.

Essentially, the provision creates different outcomes based on the question of whether the supply occurred before or after the rate change and whether the invoice and payment occurred before or after that change.

Accordingly, businesses should not assume that the rate of GST applicable on the date of invoice will always be decisive. Section 14 must be examined where a rate change occurs.

8. Time of Supply and Advances

The treatment of advances is another area where businesses must examine the statutory framework rather than commercial intuition.

For services, the receipt of payment can be relevant to determining the time of supply under Section 13. Consequently, an advance received for a taxable service can carry GST implications even though the underlying service is performed later.

For goods, the CGST framework has undergone important legislative changes in respect of the treatment of advances and the current statutory provisions should therefore be examined for the particular transaction before determining the tax point.

9. Time of Supply, Invoice and Tax Period

The legal significance of time of supply extends to the tax period during which the transaction is reported and tax is paid.

An incorrect determination can have the following consequences:

• payment of GST in the wrong tax period;
• interest consequences if tax is paid late;
• incorrect return reporting;
• reconciliation differences between books and GST returns; and
• disputes relating to the applicable rate of tax.

Accordingly, accounting teams should keep a clear trail of the relationship between the purchase/sales contract, delivery/performance records, invoice, payment records and GST return.

10. Illustrative Case Study

Consider a company providing annual maintenance services under a contract. The service is performed continuously from April to March. The contract provides for monthly payments, each becoming due on the 10th of the following month.

In such a situation the supplier cannot simply treat the entire annual contract as one GST event. The continuous-supply provisions must be applied to determine the time of supply for each relevant period.

Now assume that the GST rate changes during the contract period. The supplier must examine Section 14 separately and determine the rate of tax by considering the date of supply, invoice and payment in accordance with the statutory rule.

The example is illustrative of the fact that “when GST is payable” is a legal rather than a commercial question, requiring an analysis of statutory events and not merely the commercial date appearing on a contract.

11. Practical Compliance Checklist

Businesses can reduce time-of-supply errors by following a few basic steps:

1. Identify whether the transaction is a supply of goods or services.

2. Determine whether forward charge or reverse charge applies.

3. Check whether the supply is a continuous supply.

4. Verify the statutory invoice-issuance requirement.

5. Identify the relevant payment date and documentary evidence.

6. Apply Sections 12 or 13, as applicable.

7. If there has been a GST rate change, separately apply Section 14.

8. Ensure the transaction is reported in the correct GST return period.

9. Reconcile invoices, payments and books of account.

10. Check current amendments and notifications before finalising the tax treatment.

Conclusion

The concept of time of supply is central to the architecture of GST as it identifies the fundamental question of when a taxable transaction enters the GST liability cycle. Sections 12 and 13 of the CGST Act provide the principal rules in respect of goods and services while Section 14 addresses circumstances involving a change in the rate of tax.

The practical importance of these provisions cannot be emphasised. While a transaction may be commercially simple, its GST treatment can depend upon the precise sequence of invoicing, payment and supply. For businesses, correct determination of the time of supply aids timely tax payment, correct return reporting and reduced exposure to interest and compliance disputes.

Ultimately, time of supply should not be treated as a mere accounting date but as a statutory concept that determines the legal point at which GST liability is triggered. Careful examination of the applicable provision, invoice requirements, payment events, reverse-charge rules and rate-change provisions is therefore essential for sound GST compliance.

Key Statutory References

• Central Goods and Services Tax Act, 2017 — Section 12: Time of supply of goods.
• Central Goods and Services Tax Act, 2017 — Section 13: Time of supply of services.
• Central Goods and Services Tax Act, 2017 — Section 14: Change in rate of tax in respect of supply of goods or services.
• Central Goods and Services Tax Act, 2017 — Section 31: Tax invoice and related provisions.
• Central Goods and Services Tax Act, 2017 — Section 50: Interest on delayed payment of tax.