A reliable GST reconciliation starts before the return is prepared. Keep the purchase register, supplier documents, receipt records and portal downloads organised by period. Then work through exceptions rather than treating one total as proof that every invoice is correct.
Current portal context to keep in mind
GSTN’s FAQs introduced changes in IMS from the October 2025 tax period, including pending treatment for specified credit-note records and a facility to declare the ITC reversal amount in relevant cases. The exact document category and conditions matter. Use the official FAQ for the record you are reviewing rather than assuming every IMS entry offers the same options.
GSTR-2B is built from specified supplier and other filed information within applicable cut-offs. GSTN’s GSTR-2B FAQ explains those source records and the portal’s cut-off guidance. A difference can therefore require checking the reporting period as well as the amount.
Official reference: GSTN: IMS changes from October 2025 · GSTN: GSTR-2B FAQs
Build a repeatable monthly file
Keep the original purchase register and portal downloads unchanged. Create a separate matching worksheet using supplier GSTIN, invoice number, invoice date, taxable value and tax amount. Normalise invoice-number formatting in a working column while preserving the original reference.
Record the extraction time and the person performing the review. This small discipline helps when two team members are looking at downloads obtained on different dates.
Review exceptions with the right evidence
- Missing record: confirm the invoice and ask the supplier about reporting status.
- Value difference: compare the invoice, any amendment and your ledger posting.
- Credit note: connect it to the original transaction and document the treatment being considered.
- Duplicate record: check whether it is a duplicate or a genuinely different document.
- Period difference: identify the purchase-booking period and the portal reporting period separately.
Assign an owner and follow-up date to each exception. An unassigned mismatch often reappears in the next month without any new evidence.
An illustrative credit-note review
Suppose a supplier issues a credit note while your accounts team is still resolving a pricing dispute. Keep the original invoice, credit note, correspondence and ledger history together. Check the applicable IMS options and their conditions against the official guidance. Document why the selected action reflects the transaction; do not choose an action only to force a preferred return total.
This example is an internal review workflow, not a conclusion about credit eligibility or reversal in a particular case.
Close the review with a reconciliation note
Prepare a short bridge between the purchase register, portal information and the return working paper. List unresolved items, any separate eligibility questions and the person approving each treatment. Matching a record is only one check; a separate review of the applicable ITC conditions is still needed.
Retain the final worksheet, supporting documents and reasons for adjustments. If a notice later questions an amount, this file makes it easier to reconstruct the decision rather than relying on staff recollection. Recheck official advisories when the portal workflow changes.
Common questions
Should every difference be treated as missing credit?
No. First investigate document identity, values, reporting periods and the underlying transaction. Eligibility requires its own review.
What should the monthly exception log contain?
The document reference, difference, evidence needed, person responsible, action taken and next review date.
Official sources & review note
References checked 26 September 2026. This article is general information, not case-specific tax or legal advice. Confirm subsequent notifications and the facts of your matter before acting.
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