Overview
What is a Debit Note under GST?
A debit note is issued by a supplier to a buyer when the taxable value or tax shown on the original tax invoice was lower than what should have been charged. Section 34 of the CGST Act allows a debit note (also called a supplementary invoice) to top up the original invoice for price escalation, additional supply found post-issue, or correction of an undercharge.
Unlike a credit note, a debit note increases the supplier's output GST liability. The buyer can claim additional ITC on the debit note subject to the normal ITC time-limit (30th November of the next financial year or annual-return filing date, whichever is earlier).
A debit note must reference the original invoice number and date, and is reported in Table 9B of GSTR-1 alongside credit notes.
Use Cases
When to issue a Debit Note
- Price escalation — the contracted price increased after the original invoice was issued.
- Additional supply made on top of the original order.
- Original invoice undercharged GST (wrong rate, miscalculation, missed line).
- Adjustment for differential tax (e.g. revised classification).
Fields
Mandatory fields on a Debit Note
"DEBIT NOTE" heading
Mandatory document title.
Debit note number & date
Unique sequential, DN- prefix recommended.
Original invoice reference
Original tax invoice number and date — mandatory.
Reason for issue
Price escalation, undercharge, additional supply, etc.
Place of supply
Same as original invoice.
Additional taxable value & GST
Per-line top-up with CGST/SGST/IGST split.
How it works
Generate in 3 simple steps
Fill in details
Reference the original invoice, pick a reason code, and add the additional value being charged.
Preview live
Tax split matches the original invoice. The debit note declaration prints automatically.
Download PDF
Send to the buyer and report the debit note in Table 9B of GSTR-1.
FAQ
Frequently asked questions
Everything you need to know about debit note generation.
How is a debit note different from a fresh tax invoice?+
A debit note is a supplementary document tied to a specific earlier invoice — it adjusts that invoice. A fresh tax invoice is for an independent new supply. Use a debit note only when topping up an existing transaction.
Where do I report a debit note in GSTR-1?+
Table 9B (Credit/Debit notes — registered) for B2B and Table 9B/9C for B2C. Same place as credit notes — direction (positive value) tells the system it's a debit.
Does the buyer have to accept a debit note?+
Practically, yes — the buyer will only claim the additional ITC if they accept the debit note. If they refuse, you still owe the additional GST but they won't get the ITC.
Is there a time limit to issue a debit note?+
No statutory upper limit for issuance, but the buyer's ITC on the debit note is time-barred by 30th November of the following financial year. Issue promptly.
Can I issue a single debit note for multiple invoices?+
Yes — from 2021, a consolidated debit note covering multiple invoices is allowed, provided each original invoice reference is listed. Our PDF supports multi-invoice references.
What is the difference between a debit note and a credit note?+
A credit note reduces value/tax (return, discount, overcharge). A debit note increases value/tax (escalation, additional supply, undercharge). They're mirror images.
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