Summary: The GST Invoice Management System (IMS) allows recipients to review supplier-uploaded documents and record permitted actions before finalising input-tax-credit positions. As businesses prepare September 2026 returns, the GST Network’s October 2025 changes remain especially relevant: specified credit notes and downward amendments may be kept pending for a limited period, recipients can state the actual input tax credit to be reduced when accepting qualifying records, and remarks can accompany certain actions. The GST Network has expressly clarified that GSTR-2B generation and the auto-population of ITC into GSTR-3B have not been withdrawn; a taxpayer may still take IMS action after the normal GSTR-2B generation date and recompute the statement before filing GSTR-3B. This guide explains document-specific rules, timing, controls, supplier disputes, and the distinction between portal treatment and substantive eligibility under the CGST Act, 2017.
Why IMS needs attention before the September 2026 return
The period immediately before filing a GST return is when purchase ledgers, supplier documents and credit notes should be reconciled. For monthly taxpayers, September 2026 GSTR-3B is ordinarily due on 20 October 2026, subject to any applicable extension or taxpayer-specific condition. GSTR-2B is generally generated on the 14th of the succeeding month. The Invoice Management System (IMS) gives recipients an additional document-level workflow, but it does not replace the statutory tests for input tax credit (ITC). An invoice appearing in a statement does not by itself establish receipt of goods or services, possession of prescribed documents, business use, supplier tax-payment compliance or absence of blocked credit.
The central operational question is not whether every invoice must be clicked “Accept” before ITC can be claimed. The GST Network (GSTN) clarified on 8 October 2025 that GSTR-2B still generates automatically and eligible ITC continues to auto-populate from GSTR-2B into GSTR-3B. Recipients can take permitted IMS actions after GSTR-2B generation until the relevant GSTR-3B is filed, and can recompute GSTR-2B where appropriate. Any article or internal instruction asserting that auto-population ceased completely from October 2025 should therefore be treated cautiously against this primary-source clarification.
What records enter the IMS workflow?
The system is designed for relevant supplier-reported invoices, debit notes, credit notes and permitted amendments appearing from GSTR-1, GSTR-1A or the Invoice Furnishing Facility (IFF). The applicable action can depend on document type, whether the original document was previously accepted or rejected, and whether the corresponding GSTR-3B has already been filed. Not every record type has every action available. For example, the October 2025 enhancement specifically extended the pending option to credit notes and certain amendments for which pending had previously been unavailable. Import-related documents and other portal modules may follow their own operating rules and should not be treated as interchangeable with ordinary supplier invoices.
Accept, reject, pending and no action: four different outcomes
| IMS state | Broad portal consequence | Compliance control |
|---|---|---|
| Accept | Record considered accepted for statement processing | Verify invoice, supply and ITC eligibility |
| Reject | Record excluded or adjusted as per portal rules | Document the mismatch and coordinate with supplier |
| Pending | Specified record held for permitted limited period | Track expiry; not available for every document |
| No action | Record may be treated as deemed accepted | Never treat silence as proof of statutory eligibility |
Accept is an affirmative processing action; it does not override section 16 or section 17 of the Central Goods and Services Tax Act, 2017. Reject is a serious action because it can affect the supplier-recipient reconciliation and, in certain credit-note cases, the supplier’s tax-liability adjustment. Pending is a temporary status rather than an indefinite hold. No action may lead to deemed acceptance in the system; that mechanism is an administrative default, not a statutory warranty that every condition for ITC has been met. Businesses should maintain a reason code and supporting document for material rejections, including duplicate invoice, wrong GSTIN, wrong place of supply, unreceived goods or an unrecognised credit note.
The special pending facility from October 2025
GSTN’s official FAQ identifies the records for which the enhanced pending option was introduced: credit notes or upward amendments to credit notes; downward amendments to a credit note where the original credit note was rejected; downward amendments to invoices or debit notes where the original was accepted and the relevant GSTR-3B was filed; and certain downward amendments to e-commerce-operator documents after acceptance and filing. The eligibility is record-specific. It is incorrect to state that every credit note or every amendment can be kept pending without conditions, or that an unaccepted invoice may always be held indefinitely.
How long can a credit note remain pending?
The official GSTN FAQ describes one specified tax period: one month for a monthly recipient and one quarter for a quarterly recipient. The outer point is tied to the due date of GSTR-3B for the tax period following the GSTR-2B period to which the source document belongs. The relevant GSTR-2B period is determined by the supplier’s filing and the portal record, not merely the printed date on a credit note. After the permitted period expires, the pending action is disabled and the record is treated according to the system’s default processing rules. Finance teams should therefore record the source period, current pending date, expiry date and responsible reviewer for each held document.
| Recipient filing pattern | Permitted enhanced pending duration | Illustrative control |
|---|---|---|
| Monthly GSTR-3B | One following monthly tax period | Record GSTR-2B period and next month’s GSTR-3B due date |
| Quarterly GSTR-3B under QRMP | One following quarter | Use the correct state-wise 22nd/24th deadline |
| Record outside specified enhanced category | Do not assume pending is available | Inspect portal action eligibility and source document |
Illustration: if a qualifying credit note belongs to the September 2026 GSTR-2B period for a monthly recipient, the “one following tax period” approach points to the October 2026 GSTR-3B due date in November 2026 as the relevant outside limit, subject to the exact portal implementation and any valid deadline change. This is a workflow illustration, not a substitute for checking the actual IMS dashboard. For quarterly filers, the corresponding calculation is quarter-based and the due date depends on the principal place of business. The correct approach is to save the portal’s record-level status and due-date evidence rather than rely on a static spreadsheet alone.
Partial ITC reversal when a credit note is accepted
One practical improvement is the ability to declare the “Amount of ITC to be reduced” for specified records. Under the earlier rigid processing described in GSTN’s advisory, accepting a credit note could cause the entire GST amount of that document to be treated as a reduction even where the recipient had never taken the corresponding ITC or had already reversed part of it. The enhanced facility permits a recipient to enter the amount of credit that actually needs to be reduced, within the system’s constraints. This is a reconciliation tool; the figure must be supported by original invoice, credit note, ITC register and prior GSTR-3B reversals.
Consider an original taxable purchase carrying ₹18,000 GST. Suppose the recipient never availed any ITC on that invoice and the supplier later issues a valid credit note reducing GST by ₹9,000. The recipient should not mechanically record a second ₹9,000 ITC reversal if no corresponding ITC was ever taken. The portal’s enhanced declaration can be used to reflect the actual reversal required, supported by a clear ledger trail. Conversely, if the entire original credit was claimed and the credit note legitimately reduces tax by ₹9,000, the recipient must evaluate the corresponding ₹9,000 reversal. Both examples assume the credit note is valid and ignore other adjustments; they do not authorise retention of credit that must legally be reversed.
Why accounting and GST return figures can differ
A commercial credit note may relate to a rate reduction, quantity dispute, quality claim or a post-supply discount. The accounting entry may reduce inventory cost or expense, while the GST effect depends on the legal conditions for a tax credit note and whether tax is actually adjusted. Section 34 addresses credit notes and the statutory time limit for reporting them; section 15(3) contains conditions relevant to specified discounts. A financial credit note without GST adjustment is not necessarily the same as a GST credit note. Finance teams should classify each document and ensure the general ledger, supplier tax document, GSTR-1 record, IMS status and GSTR-3B adjustment agree.
GSTR-2B recomputation and GSTR-3B filing sequence
The GSTN clarification is clear that the normal GSTR-2B generation mechanism remains in place. If the recipient makes an IMS change after GSTR-2B has been generated, the statement may need to be recomputed so that the return preparation reflects the latest permitted action. The recomputed statement should be downloaded and reconciled with purchase registers and ITC working papers before GSTR-3B submission. Filing GSTR-3B is a significant cut-off for relevant IMS actions. Internal procedures should therefore require a pre-filing sign-off by accounts payable and GST compliance personnel, not merely an automated export from the ERP.
For September 2026, the practical timeline is to reconcile the supplier-uploaded documents already available, review the normal GSTR-2B generated around 14 October, take eligible IMS actions and recompute if necessary, then complete the GSTR-3B review before the statutory filing date. Quarterly filers have different return-period and state-specific dates. The GSTN clarification on IMS and auto-population is particularly important because incorrect assumptions about mandatory manual acceptance can create avoidable operational work or lead to an inaccurate return.
Statutory ITC conditions still govern
Section 16 of the CGST Act sets the principal eligibility conditions, including possession of prescribed tax documents, receipt of supply, conditions concerning supplier reporting and payment of tax, and filing of the return, subject to the exact statutory language and applicable amendments. Section 17(5) blocks credit for specified goods and services even if an invoice appears in GSTR-2B. Rules 37 and 37A can require reversals in defined supplier-payment or recipient-payment circumstances; Rules 42 and 43 concern attribution and reversal for common inputs, input services and capital goods. IMS does not override any of these provisions. The statutory deadline for claiming prior-year ITC is a separate issue and must be tracked independently.
The most useful monthly control is a five-way reconciliation: (1) purchase and credit-note ledger, (2) supplier tax invoices and amendments, (3) IMS actions and remarks, (4) GSTR-2B or recomputed GSTR-2B, and (5) GSTR-3B ITC and reversal tables. Differences should be coded as timing, missing supplier filing, duplicate, blocked credit, wrong GSTIN, tax-rate error, commercial dispute or already reversed. The reviewer should distinguish a mere timing mismatch from a genuine ineligible credit. A documented reconciliation reduces the risk of incorrect claims, duplicate reversals and disputes with vendors.
Supplier disputes and internal control responsibilities
When a recipient rejects a document, the supplier should receive a reasoned reconciliation request containing invoice number, date, GSTIN, taxable value, tax amount and exact issue. For credit notes, a rejection may affect the supplier’s ability to reduce output tax in the relevant period, so the commercial team should not use IMS rejection as a bargaining tool without understanding the tax consequences. Pending should be reserved for eligible records requiring genuine verification and monitored to expiry. Large businesses can establish exception dashboards by vendor and ageing; smaller businesses can use a controlled monthly register with evidence of approvals. The GSTN FAQ on enhanced credit-note pending and reversal features gives the source document categories and examples.
Primary sources and verification
- GSTN: official FAQ on IMS changes from October 2025 (PDF)
- GSTN: official GST portal and taxpayer services
- CBIC: CGST Act and Rules portal
Frequently Asked Questions
1. Must every inward invoice be manually accepted in IMS before GSTR-3B?
No. GSTN clarified that the GSTR-2B auto-generation and GSTR-3B auto-population mechanism continues. “No action” can lead to deemed acceptance, but this does not establish legal eligibility for ITC.
2. Can a September 2026 credit note be kept pending indefinitely?
No. Only qualifying records have the enhanced pending option, ordinarily for one following tax period: a month for monthly filers and a quarter for quarterly filers. The actual deadline is linked to the relevant GSTR-2B period and GSTR-3B due date.
3. What if a credit note relates to ITC never claimed?
The enhanced IMS feature allows declaration of the amount of ITC actually to be reduced for qualifying documents. Maintain the original invoice, credit note and prior ITC records to substantiate a zero or partial reversal.
4. Can I act in IMS after GSTR-2B is generated?
Yes, GSTN says permitted actions may be taken until filing the relevant GSTR-3B. If changes are made after statement generation, recompute GSTR-2B as applicable and retain the updated working.
5. Does acceptance in IMS override blocked-credit rules?
No. Section 17(5) and all other statutory ITC conditions remain applicable. IMS is a portal processing mechanism and cannot make legally ineligible credit allowable.
6. Does a supplier’s commercial credit note always require GST ITC reversal?
Not automatically. The nature of the document, whether it adjusts GST, the original ITC position, section 34 requirements and any section 15(3) discount conditions must be examined before determining the tax adjustment.
7. What records should be retained before filing September GSTR-3B?
Keep supplier invoices and credit notes, the purchase ledger, IMS action history, original and recomputed GSTR-2B, reversal calculations, exception approvals and the final GSTR-3B reconciliation.
Key Takeaways
- GSTN has not withdrawn GSTR-2B generation or ITC auto-population into GSTR-3B.
- The enhanced pending option covers specified credit notes and amendments for only one following tax period.
- The “ITC to be reduced” field can prevent duplicate or excessive reversal when supported by records.
- Section 16, section 17(5), section 34 and applicable CGST Rules govern the substantive tax position regardless of IMS status.
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Disclaimer: This article is prepared for general educational and editorial purposes from publicly available GST law and GST Network guidance reviewed as of 12 October 2026. Portal features, due dates, eligibility conditions, system validations and statutory interpretations can change, and each taxpayer must verify its own GST registration, filing pattern, state, document type and actual IMS dashboard. The examples are simplified and do not determine the correct treatment of any particular invoice, credit note, discount or tax adjustment. Readers should obtain professional advice before filing or reversing credit. TaxGuru accepts no responsibility for any tax demand, interest, penalty, vendor dispute, credit loss, filing error or other consequence arising from reliance on this publication.
