GST Section 31: Tax Invoice Rules, Timelines, Formats & Exceptions Explained

Section 31 of the CGST Act, 2017 outlines the legal requirements for issuing tax invoices, bills of supply, and other related documents under the GST regime. It specifies the timing, content, and exceptions for invoices in cases of goods, services, continuous supply, advances, refunds, and reverse charge mechanisms.

The section is supported by several GST rules (46 to 55A) and forms such as GST INV-01, receipt vouchers, and payment vouchers. Proper compliance with Section 31 ensures accurate tax reporting, Input Tax Credit eligibility, and avoidance of penalties. AUBSP emphasizes the importance of understanding these provisions for seamless GST operations.

GST Section 31: Tax Invoice Explained in Detail

As a registered taxpayer under the Goods and Services Tax (GST) regime in India, the issuance of a Tax Invoice is a critical compliance obligation. This is where Section 31 of the CGST Act, 2017 comes into the picture. In this detailed guide, we will walk you through every clause, condition, and scenario covered under Section 31, along with associated rules and notifications.

Let’s decode this important section in a simple yet professional manner so that you can ensure full compliance with GST invoicing norms.

Introduction to Section 31: Understanding the Need for Invoicing

Section 31 of the CGST Act lays down the requirements, timing, and manner in which a registered person must issue a tax invoice, bill of supply, or other relevant documents.

AUBSP emphasizes that proper issuance of invoices is not just a compliance formality, but it plays a vital role in availing Input Tax Credit (ITC), tax calculation, and audit validations.

Section 31(1): Tax Invoice for Goods

A registered person supplying taxable goods must issue a tax invoice:

• Before or at the time of:
  • (a) Removal of goods, where supply involves movement.
  • (b) Delivery or making available the goods in other cases.

The invoice must include:

1. Description of goods
2. Quantity
3. Value
4. GST charged
5. Other prescribed details

AUBSP Note: Timing of issuance is crucial. Any delay may lead to non-compliance penalties.

Section 31(2): Tax Invoice for Services

In the case of taxable services, the invoice must be issued before or after the provision of service but within the prescribed time.

Government may notify:

• Specific categories of services requiring tax invoice.
• Alternate documents that can act as tax invoices.
• Services where invoicing is exempted.

Section 31(3): Special Situations and Exceptions

This clause provides for exceptions and special types of documents to be issued in specific scenarios.

AUBSP Tip: Keep all voucher formats handy for situations involving advance or refund transactions.

Section 31(4): Continuous Supply of Goods

If the supply is continuous and involves successive payments or accounts, then:

Invoice should be issued before or at the time of each statement or payment.

Section 31(5): Continuous Supply of Services

Here’s how the invoice timing works for services:

Section 31(6): Premature Termination of Service Contracts

If the service contract ceases before full supply, then invoice must be issued at the time of cessation, covering the services rendered till then.

Section 31(7): Goods Sent on Approval for Sale or Return

When goods are sent on approval, the tax invoice must be issued:

• Before or at the time of supply, or
• Within 6 months from the date of removal, whichever is earlier.

Explanation: Meaning of Tax Invoice

For the purposes of this section, “tax invoice” includes revised invoices issued for earlier supplies.

Associated Rules and Prescribed Forms

Important Notifications Timeline

In conclusion, Section 31 of the CGST Act, 2017, is more than just a compliance rule—it’s a pillar of GST documentation and tax accountability. From issuing a standard tax invoice to managing vouchers in unique scenarios like advances, refunds, and reverse charges, a registered person must understand the scope and exceptions clearly.

AUBSP recommends maintaining clear documentation and referring to relevant rules while issuing any invoice or document under GST. Whether you’re a supplier of goods, provider of services, or a composite dealer, Section 31 applies in different capacities.

FAQs on Section 31 of the CGST Act

What is the purpose of Section 31 of the CGST Act?
Section 31 specifies when and how registered persons must issue tax invoices, bills of supply, and related documents under the GST law.

When should a tax invoice be issued for goods?
For goods, a tax invoice must be issued before or at the time of removal (if movement is involved) or at delivery (if no movement).

When should a tax invoice be issued for services?
For services, a tax invoice must be issued either before or after the provision of service but within the prescribed time limit.

What are the mandatory contents of a tax invoice?
It must include details like description, quantity, value, tax charged, supplier and recipient information, and any other particulars as prescribed under Rule 46.

Can the government notify exceptions for issuing tax invoices?
Yes, the government may notify specific goods or services for which tax invoices may be issued differently or not required at all.

What is a revised invoice under Section 31(3)(a)?
A revised invoice is issued within one month from the registration date for supplies made between the effective registration date and certificate issuance.

Is a tax invoice required for small value transactions?
No, if the value is less than ₹200 and certain conditions are met, a tax invoice may not be issued.

What is a bill of supply and when is it used?
A bill of supply is issued instead of a tax invoice when supplying exempted goods/services or under the Composition Scheme.

What document is issued for advance payments?
A receipt voucher must be issued on receiving advance payment for any goods or services.

What happens if no supply is made after advance payment?
A refund voucher should be issued to the customer if no supply follows an advance payment.

What is the requirement for reverse charge invoices?
A registered person receiving goods or services under reverse charge must issue a self-invoice and a payment voucher.

What is continuous supply of goods or services?
It refers to supplies made over a period under a contract, with successive payments or statements involved.

When should invoices be issued for continuous supply of goods?
Invoices must be issued before or at the time each statement of account is issued or payment is received.

How is invoice timing determined for continuous supply of services?
It depends on the contract—based on due date, payment receipt, or completion of an event.

What if service supply ends before completion?
An invoice should be issued at the time supply ceases, covering the portion of service rendered.

How are invoices handled for goods sent on approval?
The invoice must be issued at the time of supply or within six months from the date of removal, whichever is earlier.

Is a tax invoice required during transportation of goods?
Yes, either a tax invoice or bill of supply must accompany goods in transit as per Rule 55A.

What are the relevant rules under CGST for tax invoices?
Rules 46 to 55A of the CGST Rules govern tax invoices, bills of supply, vouchers, and special cases.

Which form is used for e-invoicing under GST?
FORM GST INV-01 is used for reporting invoices under the e-invoicing system.

What happens if a taxpayer fails to issue a tax invoice?
Non-issuance or delay in issuing a tax invoice can attract penalties and affect Input Tax Credit for the recipient.

Can a tax invoice be digitally signed and issued electronically?
Yes, tax invoices can be issued electronically and signed digitally, especially under the e-invoicing system.

Is there a provision for invoice-cum-bill of supply?
Yes, Rule 46A allows invoice-cum-bill of supply for registered persons supplying both taxable and exempt goods or services to unregistered recipients.

Can an invoice be amended after issuance?
Yes, a revised invoice or credit/debit note can be issued as per Rule 53 to reflect any changes.

What is the latest amendment to Section 31?
The Finance (No. 2) Act, 2024 amended Section 31(3)(f) and added an explanation to include suppliers registered only under TDS as unregistered for invoice purposes.

What is the effective date of Section 31?
Section 31 came into force on 1st July, 2017 through Notification No. 9/2017-Central Tax.