How this template was made: the mandatory reference to the original invoice and the serial-number requirement are taken from Section 34, the same rule explained field by field on credit and debit notes under Section 34 — laid out and the formulas written by us.
A worked example
A Ludhiana printing press invoices a client for 5,000 brochures at ₹8 a unit. The client asks for 600 extra copies after the original invoice is raised, delivered from the same print run. Same state, so CGST/SGST applies.
| Qty | Rate | Taxable value | CGST 9% + SGST 9% | Total | |
|---|---|---|---|---|---|
| Extra brochures | 600 | ₹8 | ₹4,800 | ₹432 + ₹432 | ₹5,664 |
The debit note references the original invoice's number and date, takes its own number from the debit-note series, and adjusts CGST and SGST because the original invoice did. Unlike the credit note a sales return would need, there is no deadline by which this has to be raised — it can be issued whenever the extra copies are confirmed.
What a generic invoice template usually gets wrong
- No reference to the original invoice. Without the original number and date, it is a loose adjustment, not a Section 34 debit note, and GSTR-1 rejects it.
- Numbered from the invoice series. A debit note needs its own consecutive series — mixing it into the invoice numbers leaves a gap the day one gets revised or cancelled.
- A single combined tax column instead of CGST and SGST shown separately when the original invoice was an intra-state sale — the note has to mirror the original's tax heads, not simplify them.
Questions
Why does a debit note have no deadline, unlike a credit note?
Because it increases the tax you owe rather than reduces it — there is no revenue reason to impose a cutoff on paying more. You can raise one any time after you spot the undercharge.
Does a debit note need its own serial series?
Yes — separate from your invoice series and your credit note series, consecutive within the financial year, and restarting on 1 April like the others.
I just undercharged by mistake, with nothing extra supplied — still a debit note?
Yes. A debit note covers any correction that increases the amount payable — an undercharge, a rate applied too low, or genuinely extra goods or services, all use the same document.
Where does it land in GSTR-1?
CDNR if your customer is registered, CDNUR if not — the same tables a credit note uses, just on the increasing side. Full filing mechanics: filing GSTR-1 from your invoices.
Can the customer just refuse to pay it?
That's a collections question, separate from the GST mechanics. The debit note still corrects your return and your liability regardless of whether or when the customer settles it.
How BahiSathi handles it
Raise the note from the invoice it adjusts, not from a blank document — the customer, the lines and the tax heads carry across already matched to the original. The reference to the original number and date is stored, which is what lets the GSTR-1 export place it correctly without you tracking the link by hand.
A plain-language format, not legal advice. Confirm the current position on time limits and reporting with your accountant before relying on this.