Input Tax Credit Reconciliation under Rule 36(4): A Practical Guide

Rule 36(4) of the CGST Rules, 2017 — read with section 16(2)(aa) of the CGST Act — restricts a recipient's input tax credit (ITC) to invoices that are reflected in the supplier's GSTR-1, and accordingly auto-populated in the recipient's GSTR-2B.

The current framework

Following the 2022 amendments, the rule applies on a transaction-by-transaction basis: a recipient may avail ITC only on invoices that appear in its GSTR-2B for the relevant month. Invoices not appearing in GSTR-2B (because the supplier has not filed GSTR-1, or has reported the invoice in a later period) do not entitle the recipient to ITC for that month.

Operational approach

A typical month-end ITC reconciliation involves four steps:

1. Pull GSTR-2B from the GST portal — auto-generated on the 14th of the following month.
2. Match against purchase register — invoice number, date, GSTIN, taxable value and tax amount.
3. Identify gaps — invoices in books but not in GSTR-2B (supplier has not filed) and invoices in GSTR-2B but not in books (errors or excluded items).
4. Decide ITC claim — claim ITC on matched invoices only; defer ITC on unmatched invoices to the period in which they appear in GSTR-2B.

Common reconciliation issues

• Supplier filing delays — invoices reported late by the supplier appear in GSTR-2B of a later period. ITC is available only in that later period, not the original invoice date.
• GSTIN mismatches — supplier reporting under wrong GSTIN of the recipient's group entity. ITC is denied unless corrected.
• Reversal under Rule 37 — payment to the supplier must be made within 180 days; otherwise ITC must be reversed (and re-claimed when payment is made).
• RCM credit — reverse-charge ITC follows different rules and is not subject to Rule 36(4) matching.

Recommended monthly cadence

A controlled month-end sequence helps:

• By the 14th — auto-pull GSTR-2B
• By the 17th — complete reconciliation and identify gaps
• By the 20th — file GSTR-3B with matched ITC
• By the 25th — escalate unresolved gaps with suppliers

Documentation

The reconciliation working paper should be retained for at least 72 months from the due date of filing the annual return for the relevant year, in line with section 36 of the CGST Act. Auditors and the GST authorities may request the working in the course of audit or proceedings.

For larger entities, automating the reconciliation through ERP-integrated tools is now standard practice. Even with automation, manual review of exceptions remains essential — most disputes arise from edge cases that automated tools mark for review.