In a significant compliance shift under the Goods and Services Tax regime, the GST Network (GSTN) on Saturday announced that the monthly GST payment form GSTR-3B will become non-editable from the July 2025 tax period onward. Starting with returns filed in August 2025, taxpayers will no longer be able to manually alter the tax liability in GSTR-3B once it is auto-populated — with any revisions allowed only through GSTR-1A prior to submission.According to GSTN, any changes in declared outward supplies will have to be made through form GSTR-1A before the GSTR-3B is filed for that same return period. These amendments will then be auto-populated into GSTR-3B and cannot be modified thereafter, PTI reported.“From the July 2025 tax period for which form GSTR-3B will be furnished in August 2025, such auto-populated liability will become non-editable,” GSTN stated. “Thus, taxpayers will be allowed to amend their auto-populated liability by making amendments through form GSTR-1A, which can be filed for the same tax period before filing of GSTR-3B.”GSTR-3B, a summary statement and monthly tax payment form, is filed on a staggered basis—on the 20th, 22nd or 24th of every month—depending on the taxpayer category.Currently, the portal allows taxpayers to edit the auto-populated values in GSTR-3B, which are based on information provided in forms like GSTR-1, GSTR-1A, or via the Invoice Furnishing Facility (IFF). This flexibility will be removed under the new system beginning with the July 2025 tax cycle.AMRG & Associates Senior Partner Rajat Mohan said the move aims to strengthen consistency between GSTR-1 and GSTR-3B and reduce revenue leakages. However, he noted that allowing corrections through GSTR-1A before submission is a useful safeguard.“Taxpayers must now ensure real-time reconciliation and error correction before the return is filed. This places greater responsibility on businesses to enhance internal controls and avoid last-minute adjustments,” Mohan said.