How to File GSTR-1A: Add or Amend Invoices Before Filing GSTR-3B

GSTR-1A is an optional facility for eligible regular GST taxpayers to add or correct outward-supply details for a tax period after filing GSTR-1 and before filing GSTR-3B for the same period.

Use it if you discover an invoice that was omitted from GSTR-1 or find an error in details already filed. The changes are auto-populated in your GSTR-3B liability details.

Who Can Use It and When?

The GST Portal provides this facility to regular taxpayers, including normal, SEZ and casual taxpayers. It is available to both monthly filers and quarterly filers under the QRMP scheme.

QRMP taxpayers can also amend records reported through the Invoice Furnishing Facility (IFF) for the first or second month of the quarter in GSTR-1A for that quarter.

There is no separate fixed due date for GSTR-1A. The practical deadline is before filing the corresponding GSTR-3B. GSTR-3B due dates depend on filing frequency, taxpayer location and any applicable notification, so check the GST Portal.

What Can You Correct?

You can use GSTR-1A to:

• Add outward-supply details omitted from GSTR-1 for the same period;
• Amend details already reported in that period’s GSTR-1; and
• Add or amend debit or credit notes in the relevant tables.

You cannot use it to change records from an earlier period. The recipient’s GSTIN also cannot be amended through GSTR-1A; use the prescribed process for that correction.

Input tax credit on a supply added or amended through GSTR-1A appears in the recipient’s next open GSTR-2B. The tax period in which it appears depends on when the supplier files GSTR-1A and the applicable GSTR-2B cut-off.

How to File GSTR-1A

Check the sales register and books for differences in invoices, credit notes and debit notes before filing. Verify the tax rate, place of supply, recipient details and tax amounts.

Then:

1. Log in to the GST Portal and go to Services → Returns → Returns Dashboard.
2. Select the financial year, quarter and month for the tax period.
3. Open the GSTR-1A tile when it becomes available.
4. Add missing records or amend the relevant details from the same period’s GSTR-1.
5. Review the summary and preview the statement.
6. File GSTR-1A using an available verification method, such as DSC or EVC.

Portal screens may change. Follow the instructions shown for your GSTIN and tax period.

Check the updated GSTR-3B details before filing. If the correction increases your tax liability, pay the additional tax through the applicable return process.

Important Limits and Common Errors

• GSTR-1A can be filed only once for a tax period, even if GSTR-3B has not yet been filed.
• You cannot file it after GSTR-3B for that period.
• If you save a GSTR-1A record but do not file it, the portal may prevent you from filing GSTR-3B. File GSTR-1A or delete/reset the saved record before proceeding.
• GSTR-1A cannot be filed as a nil statement.
• Do not use it to amend an earlier period. Amend that period through a later GSTR-1 within the statutory time limit.

Compare corrections with your accounting records and the customer’s invoice details. TaxClear’s GST reconciliation guide explains how to compare GST returns with books. For filing support, see TaxClear’s GST services.

Frequently Asked Questions

Is GSTR-1A mandatory?

No. It is an optional facility for adding or correcting details before filing GSTR-3B for the same period.

Can I file GSTR-1A after filing GSTR-3B?

No. GSTR-1A is available only until GSTR-3B for that tax period is filed.

Can I file GSTR-1A more than once?

No. It can be filed once for each tax period.

Will a GSTR-1A correction appear in the buyer’s same-period GSTR-2B?

It appears in the recipient’s next open GSTR-2B. The applicable period depends on filing and portal cut-off dates.

What if I find an error after filing GSTR-3B?

GSTR-1A is no longer available for that period. Correct the details through a later GSTR-1, subject to the statutory time limit.