How to File GSTR-3B Online in 2026 — Step by Step

To file GSTR-3B online, log in to the GST portal at gst.gov.in, navigate to Services → Returns → Returns Dashboard, select the tax period, and submit your summary return with tax payment. Every GST-registered taxpayer must file GSTR-3B monthly (or quarterly under QRMP), and from July 2025 onwards, most fields are auto-populated from GSTR-1 and are non-editable — making accurate invoice reporting more critical than ever.

What is GSTR-3B?

GSTR-3B is a monthly summary return filed under Section 39 of the CGST Act, 2017, read with Rule 61 of the CGST Rules. It captures:

1. Total outward taxable supplies (sales)
2. Inward supplies liable to reverse charge (RCM)
3. Input Tax Credit (ITC) claimed
4. Net GST payable after ITC set-off
5. Tax actually paid

Unlike GSTR-1, GSTR-3B does not require invoice-level details — it works on consolidated figures. But it is the return through which your actual GST liability is discharged. If GSTR-3B is not filed for a period, the portal blocks GSTR-1 filing for the next period, which freezes your buyers' ITC claims.

Use the GST Calculator to compute your output tax liability before you sit down to file.

Who Must File GSTR-3B?

Must file:

1. All regular GST-registered taxpayers
2. E-commerce operators
3. Casual taxable persons
4. SEZ developers and units

Exempt from GSTR-3B:

1. Composition dealers (file CMP-08 instead)
2. Input Service Distributors (file GSTR-6)
3. Non-resident taxable persons (file GSTR-5)
4. TDS deductors (file GSTR-7)
5. TCS collectors (file GSTR-8)

Even if there are zero transactions in a month, a nil GSTR-3B is mandatory. Skipping it attracts late fees.

GSTR-3B Due Dates for FY 2026-27

Category 1 states: Maharashtra, Karnataka, Gujarat, Goa, Tamil Nadu, Kerala, Telangana, Andhra Pradesh, and others in southern and western India.

Category 2 states: Delhi, UP, Bihar, West Bengal, Rajasthan, Punjab, Haryana, and others in northern and eastern India.

Bookmark the GST Calendar to track every due date for the full year — it updates automatically when CBIC extends deadlines.

Important (from July 2025): Under GSTN's updated policy notified via advisory dated July 2025, taxpayers cannot file GSTR-3B for a period more than three years after its original due date.

What You Need Before You Start

Gather the following before logging in:

1. GSTIN and portal login credentials
2. GSTR-1 filed and reconciled — From July 2025, Table 3 (outward supplies) and Table 3.2 (inter-state supplies) in GSTR-3B auto-populate from GSTR-1/GSTR-1A/IFF and are locked. Errors must be corrected in GSTR-1A before filing GSTR-3B.
3. GSTR-2B downloaded — This is your auto-drafted ITC statement. Cross-check it against your purchase register.
4. Electronic Cash Ledger balance — Ensure sufficient balance to cover net tax payable. Top up via GST PMT-06 if needed.
5. DSC or EVC — Digital Signature Certificate for companies; Electronic Verification Code (OTP-based) for proprietors and partnerships.

Run a GST Health Check to verify your GSTIN status and outstanding return obligations before filing.

Step-by-Step: How to File GSTR-3B Online

Step 1 — Log in to the GST portal

Go to gst.gov.in. Enter your GSTIN, username, and password. Complete CAPTCHA verification.

Step 2 — Navigate to the Returns Dashboard

From the top menu: Services → Returns → Returns Dashboard. On the File Returns page, select:

1. Financial Year: 2025-26
2. Return Filing Period: the relevant month (or quarter for QRMP filers)

Click Search.

Step 3 — Open the GSTR-3B tile

In the GSTR-3B section, click Prepare Online. The portal displays the filing due date for your selected period.

Step 4 — Answer the questionnaire

The portal presents a short questionnaire to determine which tables apply to your return. For a nil return, select Yes to "Do you wish to file Nil Return?" and skip to Step 9.

For regular returns, click through to the data entry screen.

Step 5 — Verify Table 3.1: Outward supplies

From July 2025, the values here are auto-populated from GSTR-1 and non-editable. You will see:

1. 3.1(a): Outward taxable supplies (other than zero-rated, nil, and exempted)
2. 3.1(b): Outward taxable supplies (zero-rated)
3. 3.1(c): Other outward supplies (nil-rated, exempted)
4. 3.1(d): Inward supplies (liable to reverse charge)
5. 3.1(e): Non-GST outward supplies

If any value is wrong, do not proceed. Correct it via GSTR-1A for the same period first, then return to GSTR-3B. GSTR-1A corrections reflect in GSTR-3B instantly.

Step 6 — Verify Table 3.2: Inter-state supplies

Auto-populated from GSTR-1/1A/IFF from November 2025 onwards (per GSTN advisory, December 2025). These values show inter-state supplies to unregistered persons, composition taxpayers, and UIN holders. They are non-editable. Correct via GSTR-1A if needed.

Step 7 — Enter Table 4: ITC claimed

This is one of the few sections requiring manual input. Use your GSTR-2B as the reference.

1. 4(A): Eligible ITC — import of goods, reverse charge inward supplies, ISD credit, all other ITC
2. 4(B): ITC reversed — Rule 42/43 reversals, others
3. 4(D): ITC that is ineligible under Section 17(5)

Use the ITC Calculator to compute your eligible ITC and Section 17(5) blocked credits before entering figures here. Overclaiming ITC is one of the most common GSTN scrutiny triggers.

Step 8 — Review Table 5: Exempt, nil-rated, and non-GST supplies

Enter the value of supplies that are exempt or nil-rated. These do not attract GST but must be reported.

Step 9 — Preview and verify tax computation

Click Preview Draft GSTR-3B. The portal calculates:

1. Total output tax liability (IGST + CGST + SGST + Cess)
2. Minus: ITC available
3. Equals: Net tax payable in cash

Verify every figure matches your books. Errors cannot be revised post-submission.

Step 10 — Pay tax and offset liability

Click Proceed to Payment. The portal shows:

1. Tax payable
2. Available ITC in the Electronic Credit Ledger
3. Balance in Electronic Cash Ledger

Offset ITC first (following the prescribed utilisation order under Rule 88A of the CGST Rules): IGST credit against IGST, then CGST, then SGST. Pay the remaining balance in cash.

If your cash ledger is short, generate a challan via GST PMT-06 and pay through net banking, NEFT, or RTGS before returning to offset.

Step 11 — Submit and file

Click Offset Liability → Proceed. Then:

1. Companies and LLPs: File using DSC (mandatory per CBIC notification)
2. Proprietors and individuals: File using EVC (OTP sent to registered mobile/email)

On successful filing, the portal generates an Acknowledgment Reference Number (ARN). Download and save this — it is your proof of compliance.

2025 Changes: Non-Editable Fields Explained

The GSTN introduced hard-locking of auto-populated fields in GSTR-3B from the July 2025 tax period (filed in August 2025). This is the biggest operational change in GSTR-3B since the return was introduced.

What changed:

What this means in practice: File GSTR-1 accurately and on time, every month. If you discover an error after GSTR-1 is filed, use GSTR-1A (introduced specifically for this purpose) to amend it before filing GSTR-3B. GSTR-1A can be filed without a cut-off deadline relative to GSTR-3B submission.

Late Fees and Interest

Missing the GSTR-3B deadline is costly. Under Section 47 of the CGST Act:

Interest on unpaid tax accrues at 18% per annum from the due date, under Section 50 of the CGST Act. Interest is calculated on the gross tax liability (not net after ITC), unless the amount was available in the Electronic Cash Ledger on or before the due date.

Use the Penalty Calculator and GST Interest Calculator to work out the exact amount payable before filing a delayed return.

Maximum late fee cap (as per CBIC notifications): ₹10,000 per return (₹5,000 CGST + ₹5,000 SGST) for returns with tax liability; ₹500 per return for nil returns.

Common Mistakes to Avoid

1. Not reconciling GSTR-2B before filing Claiming ITC not reflected in GSTR-2B is a mismatch trigger. Always reconcile before filing Table 4.

2. Ignoring GSTR-1 errors before the GSTR-3B deadline From July 2025, errors in GSTR-1 lock into GSTR-3B. Amend via GSTR-1A as soon as you spot them.

3. Reversing ITC incorrectly under Rule 42 ITC on inputs used partly for exempt supplies must be proportionally reversed. Miscalculation here leads to demand notices.

4. Filing without sufficient cash ledger balance Submitting GSTR-3B before paying the full tax liability results in interest accrual from the due date.

5. Skipping nil returns A nil return takes under two minutes. Skipping it costs ₹20/day in late fees and disrupts your compliance rating.

Frequently Asked Questions

Can I revise GSTR-3B after filing? No. GSTR-3B cannot be revised once filed. Errors in outward supplies must be corrected through GSTR-1A or in the next period's GSTR-1. ITC adjustments can be made in the following month's Table 4.

What is the difference between GSTR-1 and GSTR-3B? GSTR-1 reports invoice-level details of all outward supplies and is used to pass ITC to your buyers. GSTR-3B is a summary return through which you declare your net tax liability and make the actual tax payment. GSTR-1 must be filed before or alongside GSTR-3B, and from July 2025, GSTR-3B draws its outward supply figures directly from GSTR-1.

What happens if GSTR-3B is not filed for several months? Late fees accumulate at ₹50/day per return (subject to the ₹10,000 cap), interest accrues at 18% p.a. on unpaid tax, and your GSTIN may be flagged for scrutiny or suspension under Section 29 of the CGST Act. Your buyers also lose their ITC on purchases from you.

Can I file GSTR-3B for a period older than three years? No. Effective from the July 2025 tax period, GSTN has blocked filing of GSTR-3B for periods more than three years past their due date, in line with the limitation period under the CGST Act.

Who should file under the QRMP scheme and how does it affect GSTR-3B?

Taxpayers with annual turnover up to ₹5 crore can opt for the Quarterly Return Monthly Payment (QRMP) scheme. Under QRMP, GSTR-3B is filed quarterly (due on the 22nd or 24th of the month after the quarter, depending on state), but tax must still be paid monthly using Form GST PMT-06. The scheme reduces return-filing frequency while maintaining timely tax payment.