Since GST came into force in 2017, one provision quietly caused enormous grief for manufacturers, distributors, and traders across India — Section 15(3)(b) of the CGST Act.

The rule said this: if you want to deduct a post-sale discount from your taxable value, you must have agreed to it in a contract before or at the time of supply, and you must link that discount specifically to the original tax invoice. No prior agreement? No GST benefit. End of discussion.

In theory, that sounds reasonable. In practice, it was completely disconnected from how Indian businesses actually operate.

Volume rebates decided at the end of the quarter. Year-end settlement schemes. Additional discounts offered to push slow-moving inventory. Special incentives passed to a dealer based on how a market performed — none of these fit neatly into a pre-agreed, invoice-linked framework. Most businesses either didn't claim the GST reduction at all, or issued non-GST financial credit notes to avoid a litigation risk. That meant ITC piled up incorrectly in the supply chain, and tax paid on discounts that were never real income stayed with the government.

The 56th GST Council Meeting, held on 3 September 2025, recommended fixing this. The Finance Act, 2026, enacted on 30 March 2026, has now done so.

What the Finance Act, 2026 Actually Changed

The amendment operates through two provisions working together.

In Section 15(3)(b) of the CGST Act, the sub-clause requiring a pre-existing agreement and invoice linkage — Section 15(3)(b)(i) — has been omitted entirely. The law no longer asks whether the discount was agreed upon before supply or whether it is traceable to a specific invoice.

In Section 34, a corresponding amendment explicitly covers credit notes issued for post-supply discounts under Section 15(3)(b). Earlier, Section 34 listed only three grounds for issuing a GST credit note — deficient supply, incorrect tax charged, and return of goods or services. Post-sale discounts not covered by a prior agreement were a grey area. That ambiguity has been removed.

Additionally, Circular No. 212/6/2024-GST dated 26 June 2024 — which had laid out a specific compliance mechanism for establishing that the conditions under Section 15(3)(b)(ii) were met — is being rescinded. That circular was essentially administrative scaffolding around a condition that no longer exists.

What This Means for Your Business

If you give distributors, dealers, or buyers a retrospective discount — after the invoice has been raised and GST has been charged — you can now issue a GST credit note for that discount and reduce your output tax liability accordingly.

You do not need a written agreement that predates the supply. You do not need to link the credit note back to specific original invoices. The commercial reality of how you negotiate and pass on discounts now has a legal home under GST.

This matters most for:

• FMCG and consumer goods businesses that run quarterly or annual rebate schemes based on purchase volumes
• Manufacturers who pass back price corrections or market support funds to distributors after the sale
• Traders who offer year-end settlement discounts to loyal buyers
• Any business that has been issuing non-GST commercial credit notes to avoid the earlier compliance trap, and accumulating ITC incorrectly in the hands of the recipient

The One Condition That Remains — Non-Negotiable

The amendment did not remove all conditions. It removed the agreement requirement. The other condition stays firmly in place and is, if anything, more explicitly worded now:

The recipient of the supply must reverse the Input Tax Credit attributable to the discount.

This is the mechanism that keeps the tax chain clean. If you, as a supplier, reduce your output tax liability through a credit note, your buyer must correspondingly reduce the ITC they claimed on the original invoice. The GST benefit flows only when both sides act.

In practice, this means two things you need to operationally plan for:

1. When you issue a GST credit note for a post-sale discount, communicate immediately to your buyer that they need to reverse ITC in their GSTR-3B (or accept the credit note through IMS on the GST portal so the reversal is captured).
2. Do not assume the credit note alone closes the loop on your end. If the recipient does not reverse, you remain exposed.

A Note on Timing — Critical

The Finance Act, 2026 has been enacted. However, this specific amendment to Sections 15 and 34 is effective from a date to be notified in the official Gazette. As of the date of this article, that notification has not yet been issued.

What this means practically: do not restructure your entire credit note process yet. Watch for the notification. Once it is issued, the new mechanism operates — and any credit note issued after that date for a post-sale discount can follow the simplified route without worrying about agreement documentation.

For credit notes issued before the notification date, the old conditions technically continue to apply. Keep your documentation in order for those.

What About the Credit Note Deadline?

This has not changed. All GST credit notes — including those for post-sale discounts — must be issued by the earlier of:

• 30 September of the following financial year (previously 30 November; verify the applicable deadline for your period), or
• The date of filing the annual return for the year in which the original supply was made.

Miss this window, and the credit note cannot carry a GST adjustment regardless of what the amendment says.

Two Open Questions Worth Watching

Industry experts have flagged two interpretational gaps the amendment has not fully closed:

First, the term "discount" itself has not been defined or changed. Earlier case law and pre-GST era jurisprudence tied the concept of a discount to some form of pre-agreed arrangement. Whether unannounced, surprise, or stock-clearance discounts will qualify under the amended provision is not fully settled yet.

Second, the question of what constitutes a third-party consideration — particularly in cases where discounts are passed through a distributor to an end consumer — continues to be contested. If you run three-tier distribution schemes involving such arrangements, watch for further CBIC guidance.

What You Should Do Right Now

Watch for the gazette notification that operationalises the Section 15 and 34 amendments. Once it is out, review every instance where you have been issuing non-GST commercial credit notes for post-sale discounts and assess whether those can now move to proper GST credit notes. Speak to your dealer network about the ITC reversal requirement — they need to know this is coming and what it means for their GSTR-3B.

If you have pending matters with the department involving denial of post-sale discount deductions under the old Section 15(3)(b)(i), the amendment is a significant development in your favour — though its retrospective application will depend on how cases are framed.

The law has moved closer to commercial reality. That is worth recognising — and acting on.

CA Praneeth Thunuguntla | Thunuguntla & Associates | Income Tax & GST Advisory