Big GST Change from July 2026: ITC Hard Locking in GSTR-3B Explained

The GST compliance framework is becoming increasingly system-driven. After the successful implementation of hard-locking of outward tax liability, the next major reform expected from July 2026 is the hard-locking of Input Tax Credit (ITC) in GSTR-3B.

Once implemented, taxpayers will have little or no flexibility to manually edit eligible ITC while filing GSTR-3B. Instead, ITC claims will primarily be based on GSTR-2B and actions taken through the Invoice Management System (IMS).

Businesses that fail to reconcile their purchase data before filing may face blocked credits, excess tax payments, and interest liabilities.

The proposed Phase 2 of GSTR-3B automation is expected to make the ITC fields in Table 4 of GSTR-3B system-generated and non-editable for most taxpayers.

Under this framework:

• 1Eligible ITC will be auto-populated from GSTR-2B.
• 2IMS actions (acceptance, rejection or pending invoices) will directly impact ITC availability.
• 3Manual modification of ITC in GSTR-3B is expected to be significantly restricted.
• 4GSTR-3B will become primarily a tax payment return rather than a return for determining ITC eligibility.

The objective is to strengthen GST compliance by:

• 1Preventing excess or incorrect ITC claims.
• 2Ensuring supplier and recipient data match.
• 3Reducing fraudulent ITC.
• 4Improving reconciliation between GSTR-1, GSTR-2B and GSTR-3B.
• 5Making GST returns more transparent and system-driven.

The proposed change will require businesses to complete all reconciliations before filing GSTR-3B. Special attention should be given to the following areas.

1. GSTR-2B Reconciliation

Purchase registers should be reconciled with GSTR-2B every month. Missing invoices should be followed up immediately with vendors.

2. Vendor Compliance

If suppliers delay or fail to file GSTR-1 correctly, the corresponding ITC may not appear in GSTR-2B, resulting in delayed credit.

3. Invoice Management System (IMS)

Businesses must regularly monitor IMS for invoices accepted, rejected or kept pending, as these actions may affect ITC availability.

4. GSTR-1A Corrections

Suppliers should promptly rectify any invoice errors through GSTR-1A before the recipient files GSTR-3B.

5. Reverse Charge Mechanism (RCM)

Taxpayers must ensure that RCM liabilities are correctly discharged before claiming the corresponding ITC.

6. ITC Reversals

Credits requiring reversal under the GST law—such as exempt supplies, blocked credits, or non-payment to suppliers within the prescribed period—should be identified before filing the return.

To prepare for this expected change:

• 1Perform monthly GST reconciliations instead of year-end reconciliations.
• 2Monitor vendor compliance regularly.
• 3Use automated GST reconciliation tools wherever possible.
• 4Strengthen internal approval and review processes before return filing.
• 5Coordinate closely with vendors to resolve invoice mismatches promptly.

The expected ITC hard-locking in GSTR-3B marks another significant step towards a fully automated GST return system. As GST returns become increasingly driven by system-generated data, businesses must focus on accurate bookkeeping, timely reconciliations, vendor compliance, and proactive review of GSTR-2B and IMS.

Preparing in advance will help avoid blocked ITC, unnecessary tax outflows, interest costs, and future GST disputes.

PJRJ & Associates, Chartered Accountants assists businesses with:

• 1GST Return Filing
• 2GSTR-2B Reconciliation
• 3ITC Review & Advisory
• 4GST Notices & Assessments
• 5GST Litigation Support
• 6GST Health Checks

For professional GST advisory and compliance support, visit our website or get in touch with our team.