Wholesalers, distributors, and manufacturers frequently provide post supply incentives. These include volume targets, prompt payment rebates, special dealer schemes, and year-end performance bonuses. When an incentive is granted after goods are delivered, accounts departments face a recurring question: does the buyer need to reverse proportionate input tax credit, or can they retain the entire credit originally claimed in their books?
The answer hinges on whether the supplier issues a statutory GST tax credit note under Section 34 or an internal commercial credit note without tax adjustment. Knowing this distinction protects your business from unnecessary tax reversals while ensuring full compliance during audit scrutiny.
Statutory framework under Section 15(3)(b)
Under the Central Goods and Services Tax Act, the taxable value of any supply is the transaction value under Section 15(1). Discounts are excluded from taxable value either upfront on the invoice under Section 15(3)(a) or post supply under Section 15(3)(b) of the CGST Act.
For a supplier to reduce output tax liability on a post supply discount, three cumulative legal conditions must be satisfied:
- Pre-existing agreement: The discount must be established in terms of an agreement entered into at or before the time of supply.
- Invoice linkage: The discount must be specifically linked to relevant original tax invoices.
- ITC reversal by buyer: Input tax credit attributable to the discount must be reversed by the recipient based on the document issued by the supplier.
When all three conditions are satisfied, the supplier issues a GST credit note under Section 34 of the CGST Act. That credit note reduces the supplier output tax liability in Table 9B of Form GSTR-1 and auto-populates into the buyer Form GSTR-2B. In turn, the buyer must reduce input tax credit accordingly. You can read our detailed breakdown of financial credit note vs GST credit note Section 34 for procedural differences between these documents.
Common mistake: Reversing input tax credit automatically whenever a credit note arrives from a vendor. If the document is labelled commercial credit note or financial credit note and lists zero GST adjustment, reversing input tax credit creates double taxation, because the vendor has already paid full GST to the government.
Commercial credit notes and circular 92 clarification
In routine trade, many post supply discounts do not meet Section 15(3)(b) criteria. For example, a manufacturer may grant a discretionary price protection rebate or an unexpected festive volume discount that was not written into an agreement before the original dispatch. In other instances, suppliers miss the statutory deadline of 30 November under Section 34(2) to issue a tax credit note.
To settle market confusion, the Central Board of Indirect Taxes and Customs issued explicit instructions in CBIC Circular No. 92/11/2019-GST. Paragraph 2(D) clarifies the operational rules for secondary and post supply discounts:
“It is clarified that financial or commercial credit note(s) can be issued by the supplier even if the conditions mentioned in clause (b) of sub-section (3) of section 15 of the said Act are not satisfied. Since no tax has been adjusted by the supplier, the recipient will not be required to reverse the input tax credit attributable to such discount, provided the entire tax liability has been discharged by the supplier on the original invoice.” CBIC Circular No. 92/11/2019-GST, Paragraph 2(D)
Because the supplier pays full GST on the original invoice without claiming a deduction, the government exchequer has received the entire tax. Requiring the recipient to reverse input tax credit would result in the tax department collecting tax twice on the same commercial value. For broader context on input tax credit entitlement and eligibility conditions, review our guide to ITC claim rules under GST.
Why Rule 37 and 180 days non payment do not apply
A frequent challenge raised by tax officers during departmental audits stems from the second proviso to Section 16(2) read with Rule 37 of the CGST Rules. Auditors often argue that if a buyer pays an invoice value minus a commercial credit note, the buyer has failed to pay the full consideration within 180 days, triggering mandatory ITC reversal with 18% interest under Section 50.
This interpretation is incorrect under the law for two distinct reasons:
- Mutual reduction of contract debt: The second proviso to Section 16(2) applies only when the recipient fails to pay the amount payable towards the value of supply. A failure to pay denotes default or non-payment of a legally enforceable debt. When both contracting parties mutually agree to settle an account at a discounted figure, the debt itself is extinguished.
- Discharge of consideration: Under Section 2(31) of the CGST Act, consideration includes any payment or non-monetary forbearance agreed between parties. When a commercial credit note is credited to the buyer ledger, that accounting adjustment constitutes valid consideration discharging the underlying invoice.
High Court rulings across multiple jurisdictions and appellate tribunals have consistently upheld that post supply commercial discounts adjust agreed pricing rather than creating a default under Section 16(2). As long as the recipient pays the supplier the net invoice amount plus the full original tax charged on the invoice, the mandate of Section 16(2) is fully honoured.
Trade schemes note: When suppliers run promotional schemes such as free products or volume bundles alongside commercial rebates, check ITC on promotional items buy one get one to separate product discounts from free sample adjustments.
Worked numerical example: wholesaler volume rebate
Let us examine a practical transaction between Bharat Machinery Private Limited (the supplier) and Zenith Engineering Works (the buyer). Both entities are registered under GST in Maharashtra.
On 10 July 2026, Zenith buys industrial equipment worth ₹5,00,000 plus 18% GST (₹45,000 CGST and ₹45,000 SGST), resulting in a total invoice value of ₹5,90,000. Bharat Machinery deposits ₹90,000 tax in Form GSTR-3B, and Zenith avails ₹90,000 input tax credit.
On 15 August 2026, Bharat Machinery offers an unexpected post supply volume rebate of ₹50,000. Because this incentive was not established before supply, Section 15(3)(b) conditions are not met. Bharat Machinery issues a commercial credit note for ₹50,000 without tax adjustment.
| Document / Transaction | Original invoice | Commercial credit note | Net settled amount |
|---|---|---|---|
| Taxable value in ledger | ₹5,00,000 | (₹50,000) | ₹4,50,000 |
| Central GST (9%) | ₹45,000 | ₹0 | ₹45,000 |
| State GST (9%) | ₹45,000 | ₹0 | ₹45,000 |
| Total accounting value | ₹5,90,000 | (₹50,000) | ₹5,40,000 |
| Tax reported in GSTR-1 / GSTR-3B | ₹90,000 paid | No reporting | ₹90,000 intact |
| Buyer ITC in Table 4(A)(5) | ₹90,000 claimed | No reversal | ₹90,000 retained |
Zenith Engineering Works pays ₹5,40,000 via bank transfer to Bharat Machinery, completely settling the vendor ledger. The ₹90,000 tax charged by the supplier is fully recovered by the exchequer, and Zenith retains the complete ₹90,000 input tax credit.
Accounting entries in buyer books (Zenith Engineering Works)
When recording the receipt of goods on 10 July 2026:
- Debit: Purchases / Equipment Account: ₹5,00,000
- Debit: Input CGST Account: ₹45,000
- Debit: Input SGST Account: ₹45,000
- Credit: Bharat Machinery (Vendor): ₹5,90,000
When recording the commercial credit note on 15 August 2026:
- Debit: Bharat Machinery (Vendor): ₹50,000
- Credit: Discount Received / Other Income: ₹50,000
When discharging vendor payment on 20 August 2026:
- Debit: Bharat Machinery (Vendor): ₹5,40,000
- Credit: Bank Account: ₹5,40,000
Notice that the Input CGST and Input SGST accounts remain untouched throughout. No adjustment is made to tax ledgers.
GST return reporting and portal mechanics
Because commercial credit notes adjust only commercial debt, their treatment in GST return filing differs entirely from statutory tax credit notes:
Taxpayers must follow these reporting rules:
- Form GSTR-1: The supplier must not declare commercial credit notes in Table 9B. Table 9B is reserved solely for statutory credit and debit notes issued under Section 34 containing GST components.
- Form GSTR-2B: Because the commercial credit note is omitted from the supplier GSTR-1, it never auto-populates in the buyer Form GSTR-2B.
- Invoice Management System: The document does not appear on the GST portal IMS dashboard. No action such as Accept, Reject, or Pending is required.
- Form GSTR-3B: The buyer leaves Table 4(B)(1) and Table 4(B)(2) unaffected. Under CBIC Circular No. 170/02/2022-GST, Table 4(B) captures statutory reversals, whereas commercial credit notes carry no tax adjustment and require no reversal entry, preserving your net eligible credit in Table 4(C).
Audit preparation and handling scrutiny notices
During routine audits under Section 65 or scrutiny under Section 61, GST officers often examine discrepancies between total purchase turnover recorded in financial statements and total taxable turnover declared in Form GSTR-2B or Form GSTR-9. A company profit and loss account will show purchase expenditure net of discounts received, whereas Form GSTR-2B shows gross invoice figures.
To reply effectively to an ASMT-10 or DRC-01A query, maintain a dedicated reconciliation file containing the following documentation:
Requesting a simple written confirmation or vendor declaration stating that the supplier has not reduced output tax liability in Form GSTR-1 eliminates scrutiny objections quickly.
Related guides
- Pharma expired medicine ITC reversal: circular rules and procedure
- Debit note received from supplier: time limit to claim ITC under GST
- Credit note after 30th November: time limit and ITC impact
- How to calculate input tax credit and the order in which it is set off
Frequently asked questions
Does a recipient have to reverse input tax credit upon receiving a commercial credit note?
No. Under paragraph 2(D) of CBIC Circular 92/11/2019-GST, when a supplier issues a commercial or financial credit note without adjusting tax, the supplier deposits full tax on the original invoice. Consequently, the recipient is not required to reverse input tax credit.
What conditions must be met to adjust tax on a post supply discount under Section 15(3)(b)?
Section 15(3)(b) permits tax reduction only if the discount was agreed in terms of an agreement entered into at or before the supply, specifically linked to relevant invoices, and proportionate input tax credit has been reversed by the recipient.
Does receiving a post supply discount trigger the 180 days payment reversal rule under Rule 37?
No. The second proviso to Section 16(2) and Rule 37 penalise failure to pay agreed consideration. When a commercial credit note reduces the payable amount by mutual consent, paying the net invoice amount plus full original tax discharges total liability.
Should commercial credit notes be reported in Form GSTR-3B Table 4(B)?
No. Because commercial credit notes carry no GST component and the supplier does not reduce output tax liability in Form GSTR-1, no reversal entry is entered in Table 4(B)(1) or Table 4(B)(2) of Form GSTR-3B.
Do commercial credit notes show up in Form GSTR-2B or the Invoice Management System?
No. Form GSTR-2B and the Invoice Management System pull data exclusively from supplier statements in Form GSTR-1 or Form GSTR-1A. Commercial credit notes are purely internal accounting adjustments and never appear on the GST portal.
Check your own GSTR-2B
Our tool matches your purchase register against Form GSTR-2B in your browser, identifying genuine Section 34 tax credit notes while isolating commercial accounting entries. Your GSTR-2B and purchase register files are read in your browser and never uploaded to any server.
Last checked: 19 October 2026. Sources: Section 15 CGST Act, CBIC Circular 92/11/2019-GST, GSTN Portal GSTR-3B Guide.