GSTR-3B is pre-filled: the tax on your sales comes automatically from what you reported in GSTR-1, GSTR-1A or IFF. You used to be able to change those figures in GSTR-3B itself. Not any more.

What changed

From the July 2025 tax period (GSTR-3B filed in August 2025), the auto-filled tax liability is non-editable in GSTR-3B.

Why

GSTR-1A now exists. It lets you correct sales reported in GSTR-1/IFF for the same period, before filing GSTR-3B. GSTN therefore wants corrections made at the source (the sales return), not by changing figures in GSTR-3B.

How to correct a mistake

  1. Spot the error in the pre-filled GSTR-3B (or in GSTR-1 before you file).
  2. File GSTR-1A for the same tax period with the correction.
  3. GSTR-3B's figures update automatically.
  4. File GSTR-3B.

If GSTR-3B is already filed, correct the invoice in the amendment section of a later GSTR-1/IFF.

Table 3.2 (inter-state supplies to unregistered persons, composition taxpayers and UIN holders) became non-editable from the November 2025 period and is fixed the same way. See our Table 3.2 guide.

Good habits

  • Review the draft GSTR-1 carefully before filing, since that's where most errors start.
  • Keep GSTR-1A in mind as your correction window before GSTR-3B.
  • Make sure your billing software exports correct tax rates and place of supply.

Official source