Why your ITC doesn't match GSTR-2B: 12 common reasons and how to fix each

A reconciliation that throws up hundreds of "mismatches" usually has a dozen root causes. Fix the cause, not each line.

1. Supplier filed GSTR-1 late. The invoice will appear in a later month's 2B. Defer the ITC; claim it then.
2. Supplier didn't file at all. Follow up in writing. If it stays missing, the ITC is at risk - consider holding payment until they file.
3. Wrong GSTIN - the supplier used your other branch's GSTIN, or a typo. Ask them to amend in their next GSTR-1 (B2BA).
4. Invoice reported as B2C. It won't appear in your 2B at all. Ask for an amendment to B2B.
5. Invoice number formats differ. "INV/458" vs "458" - normalise before matching.
6. Date differences. Supplier's invoice date vs your booking date - match across adjacent months.
7. Amendments (B2BA). The amended invoice appears in the month of amendment, not the original month.
8. Credit / debit notes. They appear in the CDNR section; net them against the original.
9. Imports. IGST on imports appears through the ICEGATE data (IMPG section), sometimes with a delay; the bill of entry is the document.
10. Reverse charge (RCM). You pay the tax and claim the ITC yourself; these won't be supplier invoices in 2B.
11. ISD distributions. Come through the ISD section, not B2B.
12. Blocked credits. Items under Section 17(5) (motor vehicles in most cases, food and beverages, club memberships, personal use) appear in 2B but are not claimable - exclude them.

A monthly routine that prevents most of this

• Run the reconciliation before filing 3B, after 2B is generated on the 14th.
• Use IMS to reject wrong invoices.
• Send each problem supplier one consolidated email with the list of their missing or wrong invoices.
• Keep a deferred-ITC register.

Reconcile free in your browser - the tool groups mismatches by cause and drafts the supplier emails.