Amending Sales Information in GSTR-1: A Guide to Form GSTR-1A

Form GSTR-1A enables taxpayers to modify details of sales invoices initially declared in GSTR-1. This form, initially suspended shortly after GST's introduction in 2017, was reinstated in 2024. This article explores the purpose, filing deadlines, specific details, and structure of GSTR-1A.

Latest Updates on GSTR-1A

As of June 7, 2025, the GSTN announced plans to introduce hard-locking for auto-filled sales liability data in GSTR-3B, starting from the July 2025 tax period (to be filed in August 2025). This update means taxpayers will no longer be able to manually adjust values in Table 3 of GSTR-3B, which are automatically populated from GSTR-1, GSTR-1A, or IFF. Suppliers are therefore required to act swiftly and consistently via GSTR-1A on any documents that their B2B purchasers reject through the Invoice Management System (IMS).

Additionally, the GSTN, through a separate advisory, imposed a new filing deadline: taxpayers cannot submit GSTR-1, GSTR-3B, GSTR-4, GSTR-5, GSTR-5A, GSTR-6, GSTR-7, GSTR-8, and GSTR-9 returns more than three years after their respective due dates. This regulation will become effective on the GST portal from the July 2025 tax period.

On April 11, 2025, the GST Network rolled out Phase-III for Table 12 of GSTR-1 and GSTR-1A, starting with the April 2025 return period. This update mandates separate HSN-wise classification for B2B and B2C supplies within Table 12 of GSTR-1. Manual HSN code entry is no longer permitted, with taxpayers required to select HSN codes from a provided dropdown menu, as outlined in the advisory issued on the same date.

The GSTN released an advisory on January 9, 2025, concerning the compulsory inclusion of HSN codes in GSTR-1 and GSTR-1A.

Phase 3 for HSN code reporting in Table 12 of GSTR-1 and GSTR-1A went live on the GST portal starting with the January 2025 return period. This phase replaced manual HSN entry with a dropdown selection for accurate codes. A custom description from the HSN master will automatically populate a new field, 'Description as per HSN Code'. Table 12 has also been divided into B2B and B2C tabs for separate reporting of these supplies. New validations for supply values in Table 12 include: ensuring B2B supply values align across various tables (e.g., 4A, 4B, 6B, 6C, 8, 9A, 9B, 9C, 15, 15A for registered recipients) and verifying B2C supply values against other relevant tables (e.g., 5A, 6A, 7A, 7B, 8, 9A, 9B, 9C, 10, 15, 15A for unregistered recipients or exports). For amendments, only the differential value is considered for validation.

Initially, these validations operate in 'warning mode,' meaning taxpayers will receive alerts for value discrepancies but can still proceed with filing GSTR-1. Moreover, if B2B supplies are reported in other sections of GSTR-1, the B2B tab of Table 12 must not be left blank.

On July 10, 2024, the CBIC issued Notification No. 12/2024, which reintroduced Form GSTR-1A by adding a proviso to Rule 59(1). This allows for GSTR-1 amendments before GSTR-3B filing. CGST Rule 59(4A) specifies the data required in GSTR-1A. Additionally, an amendment to Rule 21(f) states that a taxpayer's GST registration may be canceled or suspended if the sales reported in GSTR-1 (including GSTR-1A amendments) exceed the sales declared in GSTR-3B.

The GST Council approved the implementation of Form GSTR-1A on June 22, 2024.

On June 18, 2024, the GST Network released GSTR-1A APIs, signaling the potential reintroduction and upcoming deployment of the GSTR-1A form on the GST portal.

What is GSTR-1A

Form GSTR-1A permits a registered taxpayer to update previously submitted sales data for GSTR-1 within the same tax period. It does not allow for amending the recipient's GSTIN. Any error in a GSTR-1 transaction can be corrected, or a missed transaction can be added, in the corresponding GSTR-1A for the same period. GSTR-1A can only be filed once per tax period.

For example, if a taxpayer files GSTR-1 for May 2025 on June 10, 2025, and identifies errors or omissions, GSTR-1A becomes active on June 11, 2025 (the later of the filing date or due date of GSTR-1). The taxpayer can then amend or add details in GSTR-1A until the GSTR-3B for May 2025 is filed on June 20, 2025. The corrected values will automatically flow into GSTR-3B.

This form, inactive since 2017, was reintroduced in July 2024 through CBIC Notification 12/2024 dated July 10, 2024, which added a proviso to Rule 59(1) to enable GSTR-1 amendments before GSTR-3B filing. CGST Rule 59(4A) further specifies the required details for GSTR-1A.

How is GSTR-1A Different from GSTR-1?

GSTR-1 serves as a comprehensive return for all sales details, filed by the selling taxpayer. While data from a seller's GSTR-1 appears in their buyer's GSTR-2B, where some information might be altered, GSTR-1A is specifically designed to accommodate amendments to GSTR-1 details for the identical month.

How Does GSTR-1A Work?

The input tax credit associated with sales reported or amended by suppliers through GSTR-1A will become accessible to recipients in the GSTR-2B of the subsequent tax period.

Consider this illustration: Ajay, a retailer, purchases 1,000 pens worth Rs. 5,000 from Vijay Wholesale Stationery. Vijay Wholesale Stationery mistakenly records this as Rs. 500 sales in their GSTR-1 for May 2025. This erroneous data then appears in Ajay's GSTR-2B. Vijay Wholesale Stationery corrects the amount to Rs. 5,000 using GSTR-1A for May 2025. Subsequently, Ajay's GSTR-2B for June 2025 reflects this alteration, which also updates Vijay Wholesale Stationery's GSTR-3B.

When is GSTR-1A to be Filed?

GSTR-1A becomes active after the filing date or the due date of GSTR-1 (whether monthly or quarterly), whichever occurs later. It can be filed at any point before the submission of GSTR-3B for the same tax period.

Details of GSTR-1A

The updated GSTR-1A format, as outlined by the CBIC, comprises 15 tables. Below, each section and the data it requires are explained:

1. GSTIN: Every taxpayer receives a 15-digit Goods and Services Taxpayer Identification Number (GSTIN) that is PAN-based and state-specific.
2. Taxpayer Name: This field includes both the legal and trade names of the taxpayer.
3. ARN: The 'Application Reference Number' and its corresponding date will be automatically populated by the system.
4. Taxable Outward Supplies to Registered Persons (excluding Table 6 supplies): This section covers amendments to standard sales invoices (not under reverse charge) and sales invoices subject to reverse charge.
5. Taxable Outward Inter-State Supplies to Unregistered Persons (Invoice Value > Rs.1 Lakh): This category includes rate-wise inter-state outward supplies to unregistered individuals, encompassing those facilitated by e-commerce operators.
6. Zero-Rated Supplies and Deemed Exports: This section addresses amendments concerning exports, supplies to SEZ units or developers, and deemed exports.
7. Taxable Supplies to Unregistered Persons (Net of Debit/Credit Notes, excluding Table 5 supplies): This heading records changes to consolidated, rate-wise intra-state supplies (including e-commerce operator supplies subject to TCS) and consolidated, rate-wise inter-state supplies up to Rs. 1 Lakh (including e-commerce operator supplies subject to TCS). If a place of supply with a specific GST rate combination was already declared in GSTR-1, new rates cannot be added via Table-7; instead, the amendment facility in Table-10 must be used.
8. Nil-Rated, Exempted, and Non-GST Outward Supplies: This section captures adjustments to inter-state and intra-state supplies made to both registered and unregistered persons, pertaining to nil-rated, exempted, and non-GST outward supplies.
9. Amendments to Taxable Outward Supply Details (GSTR-1 Tables 4, 5, 6): This includes changes to invoice/shipping bill information, original debit/credit notes, and amended debit/credit notes for the current tax period.
10. Amendments to Taxable Outward Supplies to Unregistered Persons (GSTR-1 Table 7): This section covers rate-wise adjustments to intra-state and inter-state supplies made to unregistered persons, including those handled by e-commerce operators subject to TCS.
11. Consolidated Statement of Advances and Amendments (Net of Refund Vouchers): This includes changes to advance payments received for which invoices are pending (tax added to output liability), categorized by intra-state and inter-state and reported rate-wise. It also covers advance amounts from prior periods adjusted against current supplies (Tables 4, 5, 6, and 7), similarly categorized and reported. Furthermore, it addresses revisions to information submitted in Table 11(1) of the GSTR-1 for the current period. If a specific GST rate and place of supply combination was already declared in GSTR-1, new rates cannot be added through Table-7; the amendment facility in Table-11(II) must be utilized instead.
12. HSN-Wise Summary of Outward Supplies: This table captures modifications to the HSN-wise summary of outward supplies previously reported in the GSTR-1 for the same tax period. As of April 2025, Phase-III of Table 12 for GSTR-1 and GSTR-1A requires separate HSN-wise bifurcation of B2B and B2C supplies in GSTR-1. Manual HSN entry is no longer permitted; codes must be selected from a dropdown. Downward amendments should be indicated using a minus sign for the differential amount.
13. Documents Issued During the Tax Period: This section records adjustments to documents issued within the same tax period, including invoices, revised invoices, debit and credit notes, refund vouchers, and payment vouchers.
14. Details of E-commerce Operator Supplies (Supplier Reporting): This heading records changes related to supplies made via e-commerce operators where they are responsible for tax collection under Section 52 or tax payment under Section 9(5) of the Act. 14A. Amendment to Details of E-commerce Operator Supplies (Supplier Reporting): This section captures any adjustments to supplies where the e-commerce operator is mandated to collect tax under Section 52 or remit tax under Section 9(5).
15. Details of E-commerce Operator Supplies (E-commerce Operator Reporting): This section records changes to supplies facilitated by e-commerce operators where they are liable for tax payment under Section 9(5). This data must be categorized by supplier type: registered or unregistered. 15A (I). Amendment to Details of E-commerce Operator Supplies (E-commerce Operator Reporting, Registered Recipients): This section covers amendments to supplies where the e-commerce operator is responsible for tax collection under Section 52, specifically for registered recipients. 15A (II). Amendment to Details of E-commerce Operator Supplies (E-commerce Operator Reporting, Unregistered Recipients): This section covers amendments to supplies where the e-commerce operator is responsible for tax collection under Section 52, specifically for unregistered recipients.

Format of GSTR-1A

The CBIC formally reintroduced Form GSTR-1A via Notification No. 12/2024, dated July 10, 2024.

For further details on various return types, deadlines, and filing frequencies, refer to articles on GST Returns.