Credit Notes and Debit Notes Under GST: Rules, Timing and the September Deadline

Which document, and when

Section 34(1) provides for a credit note where the taxable value or tax charged in an invoice exceeds what was actually payable, where goods are returned, or where the goods or services are found deficient. Section 34(3) provides for a debit note in the opposite case, where the value or tax charged falls short.

Both must reference the original invoice. Neither replaces it — the original stands, and the note adjusts it.

The 30 November deadline

A credit note reduces your output tax liability only if it is declared in a return by the thirtieth of November following the end of the financial year to which the original invoice relates, or the date of furnishing the annual return, whichever is earlier.

Miss it and you may still issue a commercial credit note to settle the account with your customer, but you cannot recover the GST. You have paid tax on revenue you never received, permanently. For businesses with year-end settlements and volume rebates, this deadline is the single most expensive one in the GST calendar.

Debit notes carry no such limit, for the obvious reason that they increase the tax collected.

Your reduction depends on the recipient's reversal

The proviso to Section 34(2) is the part businesses overlook. Your output liability reduces only if the recipient has correspondingly reduced their input tax credit. If they have claimed credit on the full original invoice and never reverse it, the adjustment fails at their end and the department can deny yours.

In practice this means a credit note is a two-party event. Issuing it and filing it is not enough; it has to be communicated and reconciled with the customer, which is exactly the kind of follow-up that falls through when invoices and corrections live in different systems.

What the note must contain

Rule 53 requires a credit or debit note to carry the supplier's name, address and GSTIN; the nature of the document stated prominently; a consecutive serial number unique within the financial year, not exceeding sixteen characters; the date of issue; the recipient's details; the serial number and date of the original tax invoice; the taxable value, rate of tax and the amount of tax credited or debited; and a signature.

The serial number series for credit and debit notes is separate from the tax invoice series, and each must be internally consecutive.

One note can cover many invoices

Since the 2020 amendment, a single credit or debit note may be issued against multiple invoices, which simplifies quarterly rebate settlements considerably. The note must still identify the invoices it relates to, but you no longer need one note per invoice.

Where e-invoicing applies, credit and debit notes are reportable to the Invoice Registration Portal and carry their own IRN, exactly as invoices do.

Frequently asked questions

### What is the time limit for issuing a GST credit note?

You may issue a commercial credit note at any time, but to reduce your output tax liability it must be declared in a return by 30 November following the end of the financial year of the original invoice, or the date of filing the annual return, whichever is earlier. After that the tax cannot be recovered.

### Is there a time limit for a debit note?

No. Debit notes increase the tax payable, so the law places no deadline on them. The recipient's ability to claim credit against the debit note does have a limit, which runs from the date of the debit note itself rather than the original invoice.

### Can I issue one credit note against several invoices?

Yes. Since the amendment effective February 2020, a single credit or debit note may cover multiple tax invoices, which makes period-end discount and rebate settlements far simpler. The note must still identify the invoices to which it relates.

### What if the customer refuses to reverse their input credit?

Your reduction in output liability can be denied. The proviso to Section 34(2) conditions the supplier's adjustment on a corresponding reversal by the recipient. This is why credit notes need to be agreed rather than merely issued, and why the reconciliation should be documented.