Credit Note & Debit Note Format in Excel
Last updated: 27 June 2026
A GST credit note or debit note is the only lawful way to adjust a tax invoice after it has been issued. Under Section 34 of the CGST Act, suppliers must issue a credit note when they have overcharged tax or accepted returned goods, and a debit note when they have undercharged. Both documents carry specific mandatory fields and filing deadlines that differ from a standard invoice.
Key takeaways
- You cannot amend an issued GST invoice — use a credit note (to reduce) or a debit note (to increase) instead.
- Credit notes must be issued before 30 November following the financial year of supply, or the date of filing the annual return, whichever is earlier.
- Debit notes have no upper time limit for the supplier, but the buyer's ITC window closes on the same 30 November deadline.
- Both documents must be reported in GSTR-1 Table 9 (B2B) or Table 10 (B2C large) by the 11th of the following month.
- E-invoicing applies to credit and debit notes if your aggregate turnover exceeds ₹5 crore.
- GST slabs as of June 2026: Nil, 5%, 18%, and 40% (the 12% and 28% slabs were abolished on 22 September 2025).
- An Excel template with sequential CN/DN numbering keeps you audit-ready without specialist software.
What is the difference between a credit note and a debit note under GST?
Both documents adjust a previously issued tax invoice, but they move in opposite directions.
| Scenario | Document | Effect on supplier | Effect on buyer |
|---|---|---|---|
| Tax or value overcharged | Credit note | Reduces output tax liability | Buyer must reverse ITC to the extent of the note |
| Goods returned by buyer | Credit note | Reduces output tax liability | Buyer must reverse ITC |
| Goods or services found deficient | Credit note | Reduces output tax liability | Buyer must reverse ITC |
| Tax or value undercharged (e.g., price revision upward, additional freight) | Debit note | Increases output tax liability | Buyer gets additional ITC (subject to Section 16(4) deadline) |
Fact box. Section 34(1) of the CGST Act 2017 governs credit notes; Section 34(3) governs debit notes. Both must be disclosed in the return for the month in which they are issued, or any earlier return.
What mandatory fields must appear on a GST credit note or debit note?
The CGST Rules prescribe the following fields. Missing even one can invalidate the document for ITC purposes.
- Document heading — "Credit Note" or "Debit Note" printed clearly
- A unique consecutive serial number (e.g., CN/2026-27/001 or DN/2026-27/001)
- Date of issue
- Original tax invoice number and date
- Supplier's name, address, and GSTIN
- Recipient's name, address, and GSTIN (for registered buyers)
- Description of goods or services being adjusted
- Taxable value adjusted (not the gross invoice value)
- Applicable GST rate (Nil / 5% / 18% / 40%)
- CGST, SGST / UTGST, or IGST amount adjusted separately
- Reason for issue (e.g., "Goods returned", "Price revision", "Short supply")
Fact box. For B2C supplies above ₹2.5 lakh, credit notes are reported separately in GSTR-1 Table 10 (B2C large CDN). Below that threshold they roll into Table 7 aggregate data. Always check which table applies before filing.
What are the time limits for issuing a credit note or debit note?
Credit note deadline
A credit note that reduces output tax must be issued by the earlier of:
- 30 November following the end of the financial year in which the original supply was made, or
- The date on which the annual return (GSTR-9) for that year is filed.
If you miss this window, you can still issue a commercial credit note, but you cannot use it to reduce your GST output tax liability.
Example. A supply made in March 2026 (FY 2025-26). The deadline for the credit note is the earlier of 30 November 2026 or the date you file GSTR-9 for FY 2025-26. If you file GSTR-9 on 15 October 2026, the credit note must be raised by 15 October 2026.
Debit note deadline
There is no statutory time limit on when a supplier must issue a debit note. However, the recipient's ITC on that debit note is governed by Section 16(4) — the same 30 November deadline applies to the buyer. Issue the debit note promptly so the buyer can claim ITC before that window closes.
How do you set up a credit note or debit note template in Excel?
A single workbook with a sheet toggle works well for small businesses. Here is a step-by-step approach:
- Create the header block. Place document type ("Credit Note" / "Debit Note"), your serial number, issue date, and the original invoice reference at the top.
- Mirror the invoice line items. Carry forward the original description, HSN/SAC code, quantity, and unit price. Add a column for the adjusted quantity or value.
- Build the tax calculation block. Use named ranges for CGST rate, SGST/UTGST rate, and IGST rate. The formula should reference the adjusted taxable value, not the original.
- Add a reason field. A dropdown list (Data Validation) with common reasons — "Goods returned", "Rate revision", "Deficient supply", "Price correction" — speeds entry and keeps wording consistent.
- Number sequentially. Use a separate tracking sheet with a counter. Your CN number formula:
="CN/"&FY_LABEL&"/"&TEXT(CN_COUNTER,"000"). Reset the counter on 1 April each year. - Reference the original invoice. A lookup against your invoice register can auto-populate supplier and buyer details, reducing re-keying errors.
- Print area and PDF export. Lock the print area to A1:H35 (or equivalent). Use File > Export > PDF so the document is tamper-evident when shared.
How does reporting work in GSTR-1 and GSTR-3B?
| Return | Table | Deadline | What to declare |
|---|---|---|---|
| GSTR-1 | Table 9 (B2B CDN) | 11th of following month | All B2B credit/debit notes by GSTIN of recipient |
| GSTR-1 | Table 10 (B2C large CDN) | 11th of following month | B2C credit notes for supplies > ₹2.5 lakh |
| GSTR-3B | Row 3.1 / 4B | 20th of following month | Net adjusted output tax and ITC reversal |
The recipient's GSTR-2B is auto-populated from the supplier's GSTR-1. Once auto-populated, the buyer must reverse ITC for any credit note received, ideally in the same month. If the buyer has already filed GSTR-3B for that month, the reversal happens in the next month — but interest at 18% per annum accrues on excess ITC from the original filing date until the reversal date.
Important: ITC wrongly availed and not reversed attracts interest at 24% per annum (Section 50(3)), not 18%.
Does e-invoicing apply to credit notes and debit notes?
Yes. If your aggregate annual turnover exceeds ₹5 crore, every credit note and debit note issued to a registered person must be reported to the Invoice Registration Portal (IRP) before or at the time of issuance. The IRP returns an IRN (Invoice Reference Number) and a QR code that must appear on the document.
The free Excel template described in this article includes a dedicated IRN field and QR placeholder so the printed document stays compliant even if your billing is Excel-based.
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Frequently asked questions
Can I cancel a credit note once issued?
No. A credit note cannot be cancelled once it has been issued and the relevant GSTR-1 has been filed. If the credit note was issued in error, issue a debit note for the same amount to neutralise it. Before GSTR-1 is filed you may be able to amend the entry on the portal, but the physical document remains in the record.
What happens if the buyer does not reverse ITC after receiving a credit note?
The buyer is liable for interest at 18% per annum on the ITC not reversed, calculated from the due date of the GSTR-3B in which the reversal should have been made. If the ITC was wrongly availed (i.e., never eligible), the interest rate is 24% per annum under Section 50(3).
Is there a mandatory format for the credit/debit note serial number?
The CGST Rules require numbers to be consecutive and unique within a financial year. The Rules do not mandate a specific prefix format, but using a prefix like CN/2026-27/001 prevents cross-year duplication and is a widely accepted practice in GST audits.
Do credit notes issued for exempt supplies need a GSTIN?
If the original supply was exempt and the recipient is unregistered, the credit note need not carry a GSTIN for the recipient. However, if the recipient is registered, their GSTIN is mandatory regardless of whether the supply itself was taxable or exempt.
Can a debit note increase the tax liability for a prior financial year?
Yes. A debit note can be issued for any prior period supply — there is no statutory time limit for the supplier. However, the buyer can claim ITC on that debit note only if the 30 November deadline (Section 16(4)) for the relevant financial year has not passed.
Is a credit note required for a discount given after invoice?
Yes, if the discount reduces the taxable value. Post-supply discounts that were not established in a pre-supply agreement must be effected via a credit note, and the buyer must reverse the corresponding ITC.
Sources
- CGST Act 2017, Section 34 (credit and debit notes) and Section 16(4) (ITC time limit)
- CGST Rules 2017, Rule 53 (form and manner of credit/debit notes)
- CBIC Notification 18/2022-Central Tax dated 28 September 2022 (e-invoicing threshold)
- GST Council Press Release, 56th Meeting, 3 September 2025; rates effective 22 September 2025 (slab rationalisation removing 12% and 28%)
- GSTR-1 filing instructions, GSTN portal (Tables 9 and 10)
Disclaimer. General information, not professional advice. Verify on the official portal for your case. Reviewed by a Chartered Accountant; last updated 27 June 2026.