GSTR-3B Explained

GSTR-3B is the monthly summary return you file to report your tax liability and make payment. Unlike GSTR-1 which has invoice-level detail, GSTR-3B is a consolidated return where you report totals and pay tax.

Who Must File GSTR-3B?

Every registered person (except those under the Composition Scheme) must file GSTR-3B. This includes businesses with nil outward supplies — you must file a nil return. Non-filing results in late fees, interest on unpaid tax, and inability to generate e-way bills.

Filing Deadlines

Monthly Filers

Due on the 20th of the following month. Applies to businesses with turnover above ₹5 crore or those who opted out of QRMP.

Quarterly Filers (QRMP)

Due on the 22nd or 24th of the month following the quarter (date depends on your state). Available to businesses with turnover up to ₹5 crore.

How Tax is Calculated in GSTR-3B

The basic formula for your GST liability in a period:

Tax Payable = Output Tax (Table 3.1) − Available ITC (Table 4) + Reverse Charge Tax

Output Tax is the GST you collected (or should have collected) on your outward supplies. Available ITC is the GST you paid on your inputs and can legally claim. The difference is what you owe to the government.

If your ITC exceeds your output tax, you have a credit balance — no payment is needed for that period, and the excess carries forward.

GSTR-3B Tables Explained

Table 3.1

Outward Supplies

Total value and tax on your outward supplies, broken down by taxable (inter-state and intra-state), zero-rated (exports), nil-rated, exempt, and non-GST supplies. Also includes reverse charge supplies.

Table 3.2

Inter-State Supplies to Unregistered Persons

Details of inter-state B2C supplies to unregistered persons (consolidated by state). Required for apportioning IGST revenue between states.

Table 4

Eligible ITC

Your available Input Tax Credit — auto-populated from GSTR-2B. Includes ITC available under different categories: imports, inward supplies under reverse charge, and other ITC. You can adjust this downward if some ITC is not eligible.

Table 5.1

Exempt, Nil-Rated, and Non-GST Inward Supplies

Value of inward supplies that are exempt from GST, nil-rated, or non-GST. Required even if you have no such supplies (report zero).

Table 6.1

Tax Payable

The actual tax liability calculation: outward tax minus ITC equals tax payable. This is where you determine how much GST you owe for the period.

Table 6.2

Interest

Interest payable, if any, at 18% per annum on net tax liability from the due date to the date of payment. Applies when ITC is claimed in excess or tax is paid late.

Table 6.3

Late Fee

Late fee for delayed filing: ₹50 per day (₹25 for nil returns), subject to a maximum of ₹10,000 per return. Auto-calculated by the GSTN portal.

Table 7

Payment of Tax

Tax payment through electronic cash ledger, electronic credit ledger, or bank. ITC is utilised first against output tax, and any remaining is paid in cash.

Interest and Late Fees

Item	Rate	When It Applies
Interest	18% per annum	On net tax liability from the due date to the date of actual payment. Also applies when ITC is claimed in excess.
Late Fee (Normal)	₹50 per day	For delayed filing. Maximum ₹10,000 per return (₹5,000 CGST + ₹5,000 SGST).
Late Fee (Nil Return)	₹25 per day	Reduced late fee when filing a nil return. Maximum ₹5,000 per return.

GSTR-3B vs GSTR-1

GSTR-1 and GSTR-3B serve different purposes and must be filed separately:

Aspect	GSTR-1	GSTR-3B
Purpose	Report outward supplies	Pay tax liability
Detail Level	Invoice-level detail	Summary totals
ITC Impact	Enables buyer's ITC	Uses your ITC
Due Date	11th (monthly) / 13th (quarterly)	20th (monthly) / 22nd/24th (quarterly)

Read the full GSTR-1 vs GSTR-3B comparison →

Prepare Your GSTR-3B

Use GSTSelf to prepare your GSTR-3B data before filing on the GSTN portal. Validate your figures, check for common errors, and ensure your numbers reconcile with GSTR-1.

Start GSTR-3B Preparation Reconcile with GSTR-1