Why GSTR-2B decides your ITC
GSTR-2B is the auto-drafted, static statement of input tax credit generated for each recipient every month on the GST portal. It is built from what your suppliers report in their GSTR-1 (or IFF) and other sources such as imports. Unlike the old GSTR-2A, it does not change after it is generated, which makes it the reference document for that month's claim.
Section 16(2)(aa) of the CGST Act allows input tax credit only if the details of the invoice have been furnished by the supplier and communicated to you in the auto-generated statement. From 1 January 2022, rule 36(4) limits the claim to invoices that appear in GSTR-2B. In practice: if an invoice isn't in your 2B, you can't claim it this month.
How the matching works
Each invoice is matched on supplier GSTIN plus a normalised invoice number — spaces, slashes, hyphens and dots are ignored and case doesn't matter, so 'inv/2025-26/023' and 'INV 202526 023' still match. Once matched, taxable value and IGST, CGST and SGST are compared within the tolerance you set. Each line ends up in one of four groups: matched, value mismatch, in books but not in 2B, and in 2B but not in books.
What to do with each group
Matched invoices can be claimed in GSTR-3B. Value mismatches usually mean a typing error at your end or the supplier's — check the original invoice and correct whichever side is wrong. Invoices in your books but not in 2B need supplier follow-up: the supplier may not have filed GSTR-1 or may have used a wrong GSTIN. Keep the ITC pending and claim it in the month it appears in 2B. Invoices in 2B but not in your books may be unrecorded purchases — or invoices that aren't yours, which you should reject.
Invoice Management System (IMS)
Since October 2024 the GST portal has an Invoice Management System where you can accept, reject or keep pending each invoice reported by suppliers before GSTR-2B is generated. Your actions in IMS flow into 2B. A reconciliation like this one helps you decide what to accept, reject or keep pending — doing it before the 2B cut-off saves reversals later.
Time limits to remember
Under section 16(4), ITC for invoices of a financial year can be claimed up to 30 November of the following year or the date of filing the annual return, whichever is earlier. Separately, if you do not pay the supplier within 180 days from the invoice date, the credit must be reversed with interest and can be re-claimed when you pay. Running this reconciliation every month keeps both deadlines under control.
Written by Prakash Bagchi, finance professional and founder of PB Lab. Last reviewed .