What is the difference between a credit note and a debit note in GST?

A credit note reduces the value of an original invoice — you issue it when goods are returned, discounts are given post-sale, or excess tax was charged. It reduces your output tax liability and the customer must reverse the corresponding ITC. A debit note increases the value — you issue it when additional charges apply, the original invoice understated the price, or the tax rate was too low. It increases your output tax and gives the customer additional ITC to claim. Both are governed by Section 34 of the CGST Act and must be reported in GSTR-1 Table 9.

Is there a time limit for issuing credit notes under GST?

Yes. Under Section 34(2) of the CGST Act, a credit note must be issued no later than November 30 following the end of the financial year in which the original invoice was issued, or the date of filing the annual return for that year — whichever is earlier. For example, for an invoice issued in January 2026 (FY 2025-26), the credit note must be issued by November 30, 2026 or the annual return filing date for FY 2025-26. Missing this deadline means you cannot reduce your output tax liability for that supply and must absorb the excess tax as a cost.

How do I report credit notes in GSTR-1?

Credit notes are reported in Table 9A of GSTR-1. For B2B credit notes, include the original invoice number, date, customer GSTIN, and the tax amounts being reversed. For B2C credit notes, report as consolidated adjustments by tax rate. Each credit note must have its own unique serial number separate from your invoice series. The credit note reduces your total outward supply figures in GSTR-1. When your customer sees the credit note in their GSTR-2B, they know to reverse the corresponding ITC from their records. myBillPlease auto-populates Table 9A from your credit notes.

Can a buyer issue a credit note under GST?

No, under GST only the supplier can issue a credit note. This is a common confusion. The supplier issues a credit note to reduce the invoice value. The buyer or recipient can issue a debit note to the supplier to request a price increase or additional payment. However, for GSTR-1 reporting purposes, credit notes are always reported by the supplier. If a buyer wants to reduce the amount they owe, they request the supplier to issue a credit note rather than issuing one themselves.

Does a credit note need an HSN code?

Yes, credit notes and debit notes must include HSN codes for the items being adjusted, just like regular tax invoices. The HSN code requirement follows the same turnover-based rules — 4 digits for turnover up to Rs 5 crore, 6 digits for above Rs 5 crore, and 8 digits for exports. Using incorrect or missing HSN codes on credit notes attracts the same penalty as on invoices — Rs 50 per document under Section 125 of the CGST Act, up to Rs 25,000 per year. Use the HSN code directory at mybillplease.com/hsn to verify codes.

How does a credit note affect input tax credit?

When a supplier issues a B2B credit note, the buyer must reverse the ITC they previously claimed on the original invoice — proportionate to the credit note amount. For example, if the original invoice had Rs 18,000 GST and the credit note reverses Rs 3,000 GST, the buyer must reduce their ITC by Rs 3,000 in their next GSTR-3B. This reversal appears automatically in the buyer's GSTR-2B when the supplier reports the credit note in their GSTR-1. Not reversing the ITC creates a mismatch that the GST system flags during reconciliation.

Can I create credit notes in myBillPlease?

Yes, myBillPlease fully supports credit notes as one of the 8 GST document types. To create a credit note, go to Documents, click New, select Credit Note, and choose the original invoice you are issuing the note against. Select the items being returned or adjusted, enter the return quantity or adjustment amount, and the system calculates the correct tax reversal automatically. The credit note gets its own sequential number in a separate series, includes all mandatory fields per Rule 53, and feeds into your GSTR-1 Table 9A report. For Shopify sellers, credit notes for refunded orders are created automatically.

Invoicing & Formats

Credit Note vs Debit Note in GST: When to Issue, Format, and Rules 2026

Credit notes reduce invoice value. Debit notes increase it. Both affect your GST returns, input tax credit, and GSTR-1 filing. Here is the complete guide with examples.

Himanshu23 March 2026 · 6 min read · updated 6 September 2026

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Key takeaways

A credit note reduces an invoice's value and your output tax; a debit note increases both. Never edit the original invoice.
Credit notes must be issued by November 30 following the financial year of the invoice or the annual return date, whichever is earlier.
Report credit notes in GSTR-1 Table 9A and debit notes in Table 9B, referencing the original invoice number and customer GSTIN.
Both need a separate sequential series, HSN codes, and an IRN if you are above the Rs 5 crore e-invoicing threshold.

What Are Credit Notes and Debit Notes Under GST?

In the world of GST billing, not every transaction goes as planned. A customer returns goods. You overcharged on an invoice. A discount was agreed after the invoice was issued. The tax rate applied was wrong. We see this all the time with our users. In all these situations, you cannot simply edit the original invoice — that is illegal under GST. Instead, you issue a credit note or debit note.

A credit note is issued when you need to reduce the value of an original invoice. It credits the customer — they owe you less, or you owe them a refund. A debit note is issued when you need to increase the value — the customer owes you more than the original invoice stated.

Both documents are governed by Section 34 of the CGST Act. They must be reported in your GSTR-1 (Table 9) and affect your output tax liability in GSTR-3B. Getting them wrong can cause ITC mismatches for your customer and GST notices for you.

This guide explains when to issue each, the mandatory format requirements, how they affect your GSTR-1 filing, and how to create them in myBillPlease. You can also download a free credit note format template to see the structure.

Credit Note vs Debit Note: Key Differences

Quick comparison to understand when to use which document

	Credit Note	Debit Note
Purpose	Reduce invoice value	Increase invoice value
Effect on supplier	Reduces output tax liability	Increases output tax liability
Effect on customer	Reduces ITC (must reverse)	Increases ITC (can claim more)
Common reasons	Returns, overcharging, discounts, rate errors	Undercharging, additional services, rate corrections upward
GST section	Section 34(1) CGST Act	Section 34(3) CGST Act
GSTR-1 table	Table 9A — Credit Notes	Table 9B — Debit Notes
Time limit	By Nov 30 of next FY or annual return date	No specific time limit mentioned
Issued by	Supplier (seller)	Supplier (seller) or buyer
Impact on GSTR-3B	Reduces output tax in Table 3.1	Increases output tax in Table 3.1

When to Issue a Credit Note

Section 34(1) of CGST Act specifies these situations

Goods returned by the customer — full or partial return of goods previously invoiced
Goods found deficient or defective — quality issues after delivery
Overcharging on the original invoice — wrong rate, wrong quantity, or calculation error
Post-sale discount or rebate — discount agreed after the original invoice was issued
Wrong GST rate applied — for example, charged 18% when the item is actually 5% after GST 2.0
Excess tax collected — any situation where the customer was charged more GST than applicable
Services not provided as agreed — partial non-performance of services invoiced
Shopify refund — when a customer returns an order and you process a refund in Shopify, myBillPlease auto-creates the credit note

When to Issue a Debit Note

Debit notes are less common than credit notes but equally important. You issue a debit note when the original invoice understated the value. Common situations include:

Undercharging: You invoiced Rs 10,000 but the agreed price was Rs 12,000. Issue a debit note for Rs 2,000 plus applicable GST to cover the shortfall.

Additional services: You provided extra services beyond the original scope. Rather than editing the invoice, issue a debit note for the additional amount.

Rate correction upward: If you charged 5% GST but the correct rate is 18%, issue a debit note for the GST difference. This is especially relevant after GST 2.0 where some items moved from lower to higher slabs.

Price escalation clause: In contracts with price escalation provisions, the additional amount after escalation is documented through a debit note.

Debit note timing still matters

Unlike credit notes, debit notes do not have a strict time limit for issuance. However, your customer can only claim additional ITC on a debit note within the time limit prescribed for ITC claims: by November 30 of the next financial year.

Mandatory Format: What Must Be Included

Credit notes and debit notes must contain specific fields as per Rule 53 of CGST Rules. Missing any field makes the document non-compliant:

For both credit notes and debit notes:

1. Name, address, and GSTIN of the supplier. 2. Nature of the document — clearly marked as Credit Note or Debit Note. 3. A unique sequential serial number (separate series from invoices). 4. Date of issue. 5. Name, address, and GSTIN of the recipient (for B2B). 6. Original invoice number and date being referenced. 7. Taxable value of the supply. 8. Rate and amount of tax — CGST, SGST, or IGST. 9. Signature of the supplier or authorised representative.

The credit note number must be unique and sequential — just like invoice numbers. Use a separate series like CN-001, CN-002 to distinguish from invoices. In myBillPlease, credit notes get their own auto-incrementing series. When you create a credit note, you select the original invoice, specify the return items or adjustment amount, and the system calculates the correct tax reversal automatically.

Download a free credit note format template to see the exact layout. For debit notes, use the same structure but mark it as Debit Note and ensure the additional amounts are positive.

How Credit and Debit Notes Affect Your GST Returns

GSTR-1 Reporting

Credit notes go in Table 9A. Debit notes go in Table 9B. For B2B notes, include the original invoice number and customer GSTIN. For B2C, report as consolidated adjustments.

GSTR-3B Output Tax

Credit notes reduce your output tax in Table 3.1. Debit notes increase it. The net effect changes your tax payable for the month. Credit notes effectively give you a tax refund.

Customer ITC Impact

When you issue a B2B credit note, your customer must reverse the ITC they claimed on the original invoice. The reversal appears in their GSTR-2B. Not reversing it causes ITC mismatch.

Time Limit

Credit notes must be issued by November 30 following the financial year of the original invoice, or the date of filing the annual return — whichever is earlier. Miss this deadline and you cannot reduce your tax liability.

E-Invoice for Credit Notes

If your turnover exceeds Rs 5 crore and you are required to generate e-invoices, credit notes and debit notes also need IRN from the IRP portal. The process is the same as for regular invoices.

HSN Code Requirement

Credit and debit notes must include HSN codes for the items being adjusted — same requirement as regular invoices. Use 4 or 6 digit codes based on your turnover threshold.

Practical Examples

Example 1 — Customer returns goods: You sold 100 units at Rs 500 each plus 18% GST. Total invoice: Rs 59,000 (Rs 50,000 + Rs 9,000 GST). The customer returns 20 units. Issue a credit note for Rs 11,800 (Rs 10,000 + Rs 1,800 GST). Your GSTR-3B output tax reduces by Rs 1,800. The customer reverses Rs 1,800 from their ITC.

Example 2 — Post-sale discount: You offered a 10% discount to a customer after invoicing Rs 1,00,000 + 18% GST. Issue a credit note for Rs 11,800 (Rs 10,000 + Rs 1,800 GST). This is cleaner than modifying the original invoice and maintains a proper audit trail.

Example 3 — Wrong GST rate after GST 2.0: You invoiced an item at 12% GST before September 22, 2025. After GST 2.0, the item moved to 5%. For any sales of this item from September 22 onwards that were incorrectly invoiced at 12%, issue a credit note for the 7% GST difference. This corrects the tax charged and keeps your GST 2.0 compliance clean.

In myBillPlease, creating a credit note takes 30 seconds. Select the original invoice, choose the items being returned or adjusted, and the system calculates the correct tax reversal. The credit note feeds into your GSTR-1 Table 9 automatically. No manual math, no format errors.

Create Credit Notes and Debit Notes — Free

myBillPlease supports all 8 GST document types including credit notes and debit notes. Select the original invoice, specify the adjustment, and the system handles the rest — correct tax calculation, proper format, auto-incrementing series number, and GSTR-1 reporting.

For Shopify sellers: when a customer returns an order and you process the refund in Shopify, myBillPlease automatically creates the corresponding credit note. No manual intervention needed. The credit note links to the original invoice and the tax reversal flows into your GSTR-1 and GSTR-3B reports.

Start free — create invoices, credit notes, debit notes, and all other GST documents. No credit card, no trial period.

Frequently asked questions

What is the difference between a credit note and a debit note in GST?: A credit note reduces the value of an original invoice — you issue it when goods are returned, discounts are given post-sale, or excess tax was charged. It reduces your output tax liability and the customer must reverse the corresponding ITC. A debit note increases the value — you issue it when additional charges apply, the original invoice understated the price, or the tax rate was too low. It increases your output tax and gives the customer additional ITC to claim. Both are governed by Section 34 of the CGST Act and must be reported in GSTR-1 Table 9.
Is there a time limit for issuing credit notes under GST?: Yes. Under Section 34(2) of the CGST Act, a credit note must be issued no later than November 30 following the end of the financial year in which the original invoice was issued, or the date of filing the annual return for that year — whichever is earlier. For example, for an invoice issued in January 2026 (FY 2025-26), the credit note must be issued by November 30, 2026 or the annual return filing date for FY 2025-26. Missing this deadline means you cannot reduce your output tax liability for that supply and must absorb the excess tax as a cost.
How do I report credit notes in GSTR-1?: Credit notes are reported in Table 9A of GSTR-1. For B2B credit notes, include the original invoice number, date, customer GSTIN, and the tax amounts being reversed. For B2C credit notes, report as consolidated adjustments by tax rate. Each credit note must have its own unique serial number separate from your invoice series. The credit note reduces your total outward supply figures in GSTR-1. When your customer sees the credit note in their GSTR-2B, they know to reverse the corresponding ITC from their records. myBillPlease auto-populates Table 9A from your credit notes.
Can a buyer issue a credit note under GST?: No, under GST only the supplier can issue a credit note. This is a common confusion. The supplier issues a credit note to reduce the invoice value. The buyer or recipient can issue a debit note to the supplier to request a price increase or additional payment. However, for GSTR-1 reporting purposes, credit notes are always reported by the supplier. If a buyer wants to reduce the amount they owe, they request the supplier to issue a credit note rather than issuing one themselves.
Does a credit note need an HSN code?: Yes, credit notes and debit notes must include HSN codes for the items being adjusted, just like regular tax invoices. The HSN code requirement follows the same turnover-based rules — 4 digits for turnover up to Rs 5 crore, 6 digits for above Rs 5 crore, and 8 digits for exports. Using incorrect or missing HSN codes on credit notes attracts the same penalty as on invoices — Rs 50 per document under Section 125 of the CGST Act, up to Rs 25,000 per year. Use the HSN code directory at mybillplease.com/hsn to verify codes.
How does a credit note affect input tax credit?: When a supplier issues a B2B credit note, the buyer must reverse the ITC they previously claimed on the original invoice — proportionate to the credit note amount. For example, if the original invoice had Rs 18,000 GST and the credit note reverses Rs 3,000 GST, the buyer must reduce their ITC by Rs 3,000 in their next GSTR-3B. This reversal appears automatically in the buyer's GSTR-2B when the supplier reports the credit note in their GSTR-1. Not reversing the ITC creates a mismatch that the GST system flags during reconciliation.
Can I create credit notes in myBillPlease?: Yes, myBillPlease fully supports credit notes as one of the 8 GST document types. To create a credit note, go to Documents, click New, select Credit Note, and choose the original invoice you are issuing the note against. Select the items being returned or adjusted, enter the return quantity or adjustment amount, and the system calculates the correct tax reversal automatically. The credit note gets its own sequential number in a separate series, includes all mandatory fields per Rule 53, and feeds into your GSTR-1 Table 9A report. For Shopify sellers, credit notes for refunded orders are created automatically.