GSTR-2B vs purchase register: how ITC reconciliation works

Input Tax Credit (ITC) is the GST a registered business has paid on its purchases and can set off against the GST it collects on sales. Since the auto-drafted statement GSTR-2B became the reference for eligible credit, a monthly reconciliation between GSTR-2B and the business’s own purchase register is the control that keeps a GSTR-3B claim defensible.

What GSTR-2B actually is

GSTR-2B is a static, month-wise statement generated for each recipient from the returns filed by its suppliers (mainly GSTR-1 / IFF and GSTR-5). “Static” matters: once generated for a tax period it does not change, so it is a stable snapshot to reconcile against — unlike GSTR-2A, which keeps updating as suppliers file late. GSTR-2B also carries an advisory on each invoice: whether the credit is available, and if not, why.

The reconciliation, step by step

• Match on invoice key. Line up each purchase-register invoice against GSTR-2B on supplier GSTIN + invoice number + date + taxable value + tax amounts.
• Classify the differences. In-books-not-in-2B (supplier hasn’t filed, or filed in a different period), in-2B-not-in-books (missed recording, or not your invoice), and matched-but-values-differ (rate, taxable value or tax head mismatch).
• Test eligibility separately. An invoice appearing in GSTR-2B is not automatically claimable — the recipient still has to apply the Section 17(5) blocked-credit list and business-use tests.

Section 17(5) — blocked credits

Section 17(5) of the CGST Act denies ITC on specified inward supplies regardless of what GSTR-2B shows — common categories include motor vehicles for personal use, food and beverages, membership of clubs, works contract and construction of immovable property (with carve-outs), and goods lost, stolen or given as free samples. A reconciliation that only matches invoices but never flags Section 17(5) items overstates the eligible credit.

The two failures a reconciliation must surface

First, vendor filing gaps: credit you have booked but which is not (yet) in GSTR-2B because the supplier has not filed — this is a cash-flow and follow-up issue, and claiming it before it appears invites a mismatch notice. Second, ineligible credit that slipped through: an invoice that is in GSTR-2B and in your books but is blocked under Section 17(5) or is not for business use. Both need to be visible before GSTR-3B is filed.

How FinRace AI helps

The CA workspace runs a deterministic GSTR-2B vs purchase-register reconciliation — no LLM in the matching — that classifies every difference and flags Section 17(5) ineligible-credit lines. From the reconciliation it can produce a draft ASMT-10 reply. It does not file GSTR-3B for you, and it is not a substitute for a CA’s review of borderline eligibility calls.