Published Quick answer — the GST Invoice Management System (IMS) in 2026:
| Action in IMS | What happens |
|---|---|
| Accept | The record goes to the "ITC Available" section of GSTR-2B and the credit auto-populates in GSTR-3B. |
| Reject | The record goes to "ITC Rejected" in GSTR-2B; no credit flows to GSTR-3B. |
| Pending | The record stays on the IMS dashboard and out of GSTR-2B and GSTR-3B. Credit notes can be kept pending for one tax period only (one month, or one quarter for QRMP filers). |
| No action | Deemed accepted when GSTR-2B is generated on the 14th of the following month. |
The Invoice Management System (IMS) is the screen on the GST portal where a buyer sees every invoice, debit note and credit note that its suppliers have reported, and decides what to do with each one before the month's input tax credit is worked out. GSTN made it available from 1 October 2024. For most businesses it has quietly become the place where the month-end ITC reconciliation now happens.
What is the Invoice Management System under GST?
When a supplier reports a B2B document in GSTR-1, IFF or GSTR-1A, the record appears in the recipient's IMS. The recipient can accept it, reject it or keep it pending. Those actions decide what goes into the recipient's GSTR-2B, and GSTR-2B decides the credit that auto-populates in GSTR-3B.
IMS does not change the law on who may take credit. A credit is still allowed only if the conditions in section 16 of the CGST Act are met and it is not blocked by section 17(5). Accepting an invoice in IMS records your agreement with the supplier's data; it is not proof that the credit is eligible.
How accept, reject and pending work
- Accept: the record is shown under "ITC Available" in GSTR-2B and its tax auto-populates in GSTR-3B as eligible credit.
- Reject: the record is shown under "ITC Rejected" and does not reach GSTR-3B. Reject when the invoice is wrong, is not yours, or the goods or services were never received.
- Pending: the record stays on the IMS dashboard and does not reach GSTR-2B or GSTR-3B until you act on it. Use it for invoices where the goods are in transit or the invoice is under dispute.
- No action: GSTN treats the record as deemed accepted when GSTR-2B is generated.
The monthly IMS timeline
- During the month: supplier records appear in IMS as suppliers file GSTR-1 or IFF. You can act on them as they arrive.
- 14th of the following month: the draft GSTR-2B is generated. Anything you have not acted on is deemed accepted.
- After the 14th and before filing GSTR-3B: you can still change actions, but you must recompute GSTR-2B on the portal so that GSTR-3B picks up the change.
- After GSTR-3B is filed: no further action is possible for that period.
What does not go through IMS
Two categories bypass IMS and flow directly to GSTR-3B: inward supplies on reverse charge that the supplier reported in Table 4B of GSTR-1, IFF or GSTR-1A; and records where credit is not available because of the time limit in section 16(4) or the place-of-supply rules.
What changed from the October 2025 tax period
Two changes took effect from the October 2025 tax period (GSTN advisory of 17 October 2025).
- Pending option for credit notes. A recipient can keep a credit note (and certain amendments) pending, but only for one tax period: one month for monthly filers and one quarter for QRMP filers. After that window, the record must be accepted or rejected; if nothing is done, it is deemed accepted.
- Declaring the ITC to be reduced. When accepting a credit note, the recipient answers whether credit needs to be reduced and can enter the actual amount to be reversed. Leaving the amount blank means the full amount is reversed. This helps when the credit was never taken in full.
GSTN also clarified on 8 October 2025 that GSTR-2B will continue to be generated and to auto-populate GSTR-3B, so manual acceptance of every record is not compulsory.
These changes sit alongside the amendment to section 34(2) of the CGST Act, in force from 1 October 2025 (Notification No. 16/2025-Central Tax dated 17 September 2025). A supplier's output tax can be reduced through a credit note only if the registered recipient has reversed the matching credit. A recipient who rejects or ignores a valid credit note therefore affects the supplier's GST position as well as its own.
A practical monthly IMS routine
- Download the IMS records in the first week of the month and match them against your purchase register.
- Accept records that match, are received and are eligible under sections 16 and 17.
- Keep pending the invoices for goods in transit or under query, and note why.
- Reject records that are not yours, are duplicated or are wrong, and tell the supplier the same day so it can amend through GSTR-1A.
- For credit notes, decide within the one-period window and enter the correct reduction amount.
- After the 14th, recompute GSTR-2B if you changed any action, then file GSTR-3B.
- Keep the working file with the month's GSTR-3B papers. It is what an officer will ask for in a scrutiny or audit.
Frequently asked questions
Is it compulsory to accept invoices in IMS?
No. Records you do not act on are deemed accepted when GSTR-2B is generated. The risk is in the opposite direction: deemed acceptance can carry an ineligible or wrong invoice into GSTR-3B, so the review is worth doing.
Can I keep an invoice pending indefinitely?
Invoices can be kept pending while you resolve them, but credit is still subject to the time limit in section 16(4): 30 November following the end of the financial year, or the date you file the annual return, whichever is earlier. Credit notes can be kept pending for one tax period only.
Does rejecting an invoice reduce my supplier's liability?
Rejecting an invoice does not reduce the supplier's liability; the supplier must correct its own return. Rejecting a credit note can, after the section 34(2) amendment, stop the supplier from reducing its output tax.
What happens to reverse charge invoices?
Supplies on reverse charge reported in Table 4B of GSTR-1 or IFF do not go through IMS; they go directly to GSTR-3B.
Related guides
- Input tax credit under GST: conditions, time limit and the 30 November 2026 deadline
- GST return due dates for FY 2026-27
- How to handle GST and income-tax notices
Sources
- CGST Act, 2017 — sections 16, 17(5), 34 and 38 (cbic-gst.gov.in)
- Notification No. 16/2025-Central Tax dated 17 September 2025 (commencement of Finance Act, 2025 amendments from 1 October 2025)
- GSTN advisory on the Invoice Management System (tutorial.gst.gov.in)
- GSTN advisories of 8 October 2025 and 17 October 2025 on IMS changes (gst.gov.in — News and Updates)
Regi Tom Antony & Associates helps businesses in Kochi and across Kerala set up a monthly IMS and ITC reconciliation that holds up in scrutiny and audit. See our GST compliance services and GST audits, or contact us.