GSTR-2B reconciliation, and why it is the one that pays for itself
If you claim input tax credit, this is the check that decides whether you keep it.
GSTR-2B is a statement the portal generates for you each month, listing the input tax credit available from what your suppliers actually filed. Your books, meanwhile, list the credit you think you have. Reconciliation is putting those two side by side - and the gap between them is real money.
2B is a statement, not a return
You do not file GSTR-2B. The portal generates it, and it is static: once generated for a period, it does not change. That is the point - it is the fixed record of what was available to you as of that date, which is what makes it something you can reconcile against rather than a moving target.
It is generated after the deadline for suppliers' GSTR-1 for the period, so it reflects what they filed on time.
Why the gap matters
Input tax credit is broadly restricted to what appears in your 2B. So a purchase bill you have, entered correctly, with tax you genuinely paid, is credit you may not be able to claim if your supplier has not filed it.
Nothing anywhere tells you this has happened. Your books look right, the bill is in your file, and the credit simply is not there. The only way to find out is to compare - and to find out this month, while the supplier still remembers the invoice and can correct it, rather than at the year end.
Doing the reconciliation
- 1Download GSTR-2B for the period from the portal, in JSON or Excel.
- 2Pull your own purchase register for the same period.
- 3Match on GSTIN plus invoice number plus date. Amounts will match too, but the identity is those three.
- 4Sort what falls out into: in 2B but not in your books, in your books but not in 2B, and in both but with different figures.
- 5Chase the second group. Those are the suppliers who have not filed, or who filed against a wrong GSTIN.
- 6Investigate the third group before claiming - a difference in taxable value or in the tax split is a real disagreement about the invoice.
What to do about a supplier who has not filed
Contact them with the invoice details and ask when they are filing. Most cases are ordinary - a bill missed, or your GSTIN typed wrong so the credit went to nobody.
Keep the correspondence. If it becomes a habit with a particular supplier, that is commercial information about them as much as it is a tax problem, and it is worth knowing before the next order.
How Zembook handles it
Download the portal's own 2B and Zembook matches it against the purchase entries you already made, producing exactly the three lists above. What comes out is the one that matters: which supplier has not filed your bill, and therefore which credit you are about to claim and lose.
Reviewed August 2026. This describes general GST practice and is not tax advice. Thresholds, due dates and rules change by notification, and several vary by state — confirm anything that decides a filing on gst.gov.in or with your accountant.
Questions people ask
- What is the difference between GSTR-2A and GSTR-2B?
- 2A is dynamic - it keeps changing as suppliers file, including for old periods. 2B is static: generated once for a period and fixed after that. Reconciliation is done against 2B precisely because it does not move.
- Can I claim credit that is not in my 2B?
- Credit is broadly restricted to what appears in 2B, and claiming outside it invites a demand with interest. The practical answer is to get the supplier to file rather than to claim and hope.
- How often should I reconcile?
- Every month, as soon as 2B is generated. The whole value of doing it is that a missing invoice is fixable while it is recent - a year-end reconciliation finds the same problems when nothing can be done about them.
Zembook does this part for you
GSTR-1 and GSTR-3B as portal-ready JSON computed from your own vouchers, GSTR-2B reconciliation against your purchases, reverse charge reported separately, e-Way Bill and e-Invoice files.