Why the reconciliation matters
Since 1 January 2022, section 16(2)(aa) of the CGST Act, 2017 allows credit only where the supplier has furnished the invoice in its GSTR-1 and the details have been communicated to the recipient. Rule 36(4) of the CGST Rules limits credit to invoices that appear in GSTR-2B. Credit in the books that is not in GSTR-2B cannot be claimed in GSTR-3B for that period.
A monthly routine
- Download GSTR-2B once it is generated for the period.
- Match the purchase register to GSTR-2B by supplier GSTIN, invoice number, date and tax amount.
- Classify differences: missing in GSTR-2B, missing in the books, value or tax mismatches, and credits blocked under section 17(5).
- Follow up suppliers whose invoices are missing, and carry those invoices forward until they appear.
- Claim in GSTR-3B only the credit that the reconciliation supports, and keep the working with the return.
Time limits and reversals
- Credit for a financial year must be claimed by 30 November of the following year, or the date of filing the annual return if earlier (section 16(4)).
- Where a supplier is not paid within 180 days of the invoice date, the credit is reversed, and can be claimed again on payment (section 16(2) and rule 37).
- Where a supplier has not filed GSTR-3B for the period by 30 September following the year end, the recipient reverses the credit by 30 November (rule 37A).
References
- CGST Act, 2017, sections 16 and 17(5)
- CGST Rules, 2017, rules 36(4), 37 and 37A
This note is general information on the law as at October 2026. It is not advice for any specific situation.