You raised an invoice for ₹50,000 and the client accepted it. Then you realise you charged the wrong rate — it should have been ₹58,000. Or you agreed to pass on a freight cost that wasn’t on the original invoice. Or additional work was done after the invoice was closed. You can’t edit the original invoice. You issue a debit note for the difference.
Fill in the original invoice details below, enter the additional amount as the line item, and download.
What a debit note does
A debit note increases the taxable value and the corresponding GST from a previous invoice. From the supplier’s side, it means more tax is owed to the government on that supply. From the buyer’s side, their input tax credit goes up — they can claim more ITC because the supplier is now charging more.
The word “debit” refers to the buyer’s account being debited — the buyer now owes more. The supplier issues the note to formally document the upward revision.
When to issue a debit note
The most common situations:
Undercharge on original invoice — You quoted ₹40 per unit but invoiced at ₹38 by mistake. The debit note covers the ₹2 per unit difference across all units supplied.
Additional services rendered — After closing an invoice, additional work was done. Rather than raising a fresh invoice for a continuing engagement, a debit note against the original invoice keeps the paper trail clean.
Price revision post-supply — Commodity prices or input costs increased and the revised price was agreed after the goods were delivered. The debit note formalises the increase.
Freight or insurance charges not billed — Commonly happens in goods supply when freight is paid by the supplier and then charged back. If the original invoice didn’t include it, a debit note covers it.
Debit note vs credit note: the core difference
Both adjust a previous invoice. The direction is the difference.
A credit note reduces what the buyer owes. Goods returned, overcharge corrected, post-sale discount applied.
A debit note increases what the buyer owes. Undercharge corrected, additional charges added, price revision upward.
Under GST, both are issued by the supplier. The buyer cannot unilaterally issue a debit note to the supplier as a formal GST document (though some businesses do it for internal accounting — that’s a different thing and doesn’t affect GST filings).
Time limit for debit notes under GST
Unlike credit notes, GST law has no deadline for issuing debit notes. A credit note for FY 2025-26 must be issued before September 30, 2026 (or the annual return date, whichever is earlier). A debit note has no such restriction — you can issue one at any time. The tax impact takes effect in the return period when the debit note is issued and reported in GSTR-1.
What to put on a GST debit note
The required fields mirror a tax invoice: your GSTIN, the buyer’s GSTIN, the debit note number (sequential, separate series from invoices), date, original invoice number it relates to, reason for the revision, the additional taxable value, GST rate and amount (CGST+SGST or IGST, matching the original invoice’s mode), and revised total.
In the generator above, use the notes field to reference the original invoice: “Debit note against Invoice #INV-2026-087 dated 01-Aug-2026 — price correction for 200 units at revised rate of ₹42/unit.”
Related: credit note template for downward adjustments, and the GST invoice template for the original invoice format.