GST Return Due Dates 2026: GSTR-1 & GSTR-3B Calendar

Filing GST returns on time is one of the most critical compliance tasks for any business registered in India. Missing a GST return filing due date 2026 can result in heavy late fees, 18% annual interest, and even the blocking of your E-way bills.

If you are a freelancer, consultant, or small business owner, this complete GST return filing calendar India will help you track your monthly and quarterly deadlines.

What Are GST Returns?

A GST return is a document containing details of all the income (sales) and expenses (purchases) that a taxpayer must file with the Indian tax authorities. The government uses this return to calculate your net tax liability. When you generate a bill using our Free GST Invoice Generator, those exact invoice details must be reported in your return. Missing a GST return due date in India isn't just an administrative hassle; it immediately triggers a daily late fee and interest on any unpaid tax. Whether you are a newly registered freelancer, a small business using the QRMP scheme, or a large enterprise, tracking your compliance calendar is essential.

In this guide, we break down the GST return due dates for 2026, explain the difference between GSTR-1 and GSTR-3B, and provide a full month-by-month calendar to keep you penalty-free.

Month-by-Month GST Return Filing Calendar (2026)

If you are a regular taxpayer filing monthly returns, mark these dates in your calendar. GSTR-1 is always due on the 11th, and GSTR-3B is always due on the 20th of the month following the billing period.

| Billing Month | GSTR-1 Due Date (Sales) | GSTR-3B Due Date (Tax Payment) | | --- | --- | --- | | January 2026 | 11th February 2026 | 20th February 2026 | | February 2026 | 11th March 2026 | 20th March 2026 | | March 2026 | 11th April 2026 | 20th April 2026 | | April 2026 | 11th May 2026 | 20th May 2026 | | May 2026 | 11th June 2026 | 20th June 2026 | | June 2026 | 11th July 2026 | 20th July 2026 | | July 2026 | 11th August 2026 | 20th August 2026 | | August 2026 | 11th September 2026 | 20th September 2026 | | September 2026 | 11th October 2026 | 20th October 2026 | | October 2026 | 11th November 2026 | 20th November 2026 | | November 2026 | 11th December 2026 | 20th December 2026 | | December 2026 | 11th January 2027 | 20th January 2027 |

(Note: Due dates are strictly enforced but may change due to official CBIC notifications or GST portal technical issues. Always consult the official GST portal for real-time extensions.)

Quarterly Returns: QRMP Scheme Due Dates

The Quarterly Return Filing and Monthly Payment of Taxes (QRMP) scheme is designed for small businesses and freelancers with an annual aggregate turnover of up to ₹5 Crores. Under this scheme, you file returns quarterly but must pay your estimated tax monthly using form PMT-06.

QRMP GSTR-1 & GSTR-3B Calendar (2026-27)

| Quarter | Months Included | GSTR-1 Due Date | GSTR-3B Due Date | | --- | --- | --- | --- | | Q1 (Apr-Jun) | April, May, June | 13th July 2026 | 22nd / 24th July 2026 | | Q2 (Jul-Sep) | July, August, September | 13th October 2026 | 22nd / 24th October 2026 | | Q3 (Oct-Dec) | October, November, December | 13th January 2027 | 22nd / 24th January 2027 | | Q4 (Jan-Mar) | January, February, March | 13th April 2027 | 22nd / 24th April 2027 |

Note on GSTR-3B QRMP Dates:

• 22nd of the month: For businesses located in Category X States (Southern and Western states like Maharashtra, Karnataka, Gujarat, Tamil Nadu).
• 24th of the month: For businesses located in Category Y States (Northern and Eastern states like Delhi, UP, Bihar, West Bengal).

CMP-08 & GSTR-4 Due Dates for Composition Dealers

If you have opted for the GST Composition Scheme to reduce your compliance burden, you do not file the standard GSTR-1 or GSTR-3B. Instead, you file a simple statement called Form CMP-08 every quarter, and an annual return called GSTR-4.

• CMP-08 Due Date: 18th of the month succeeding the quarter. (e.g., For April-June quarter, it is due by 18th July).
• GSTR-4 Due Date: 30th April following the end of the financial year.

GST Late Fee for Delayed Returns

If you miss your GST return due dates, you will be automatically penalized by the GST portal. The standard GST late fee for return filing under the CGST Act is:

• Standard Return: ₹50 per day (₹25 CGST + ₹25 SGST) of delay.
• Nil Return: ₹20 per day (₹10 CGST + ₹10 SGST) of delay. A "Nil return" means you had absolutely no sales or purchases in that billing period.

Maximum Cap: To provide relief to small taxpayers, the maximum late fee is capped at ₹2,000 for standard returns and ₹500 for Nil returns per filing period.

GST Interest on Late Tax Payment

Aside from the flat daily late fee, if you owe the government tax money and pay it after the due date, you must pay interest on the outstanding liability.

• The statutory interest rate is 18% per annum.
• It is calculated on the net tax liability (Tax Owed minus available Input Tax Credit).
• Interest is calculated from the day following the due date until the actual date of payment.

Example Late Fee & Interest Calculation

Imagine you are a freelancer who missed filing your May 2026 GSTR-3B. The due date was 20th June 2026. You finally file it on 30th June 2026 (a delay of 10 days). You owe ₹10,000 in net tax.

• Late Fee: 10 days x ₹50/day = ₹500.
• Interest: ₹10,000 x 18% x (10 days / 365 days) = ₹49.31.
• Total Extra Penalty: You will pay your ₹10,000 tax plus ₹549.31 in penalties.

How to Avoid GST Return Filing Penalties

1. Set Calendar Reminders: Add the 11th and 20th to your Google Calendar with a 3-day advance alert.
2. Reconcile Early: Don't wait until the 20th. Reconcile your sales invoices against your bank account by the 5th of every month.
3. File Nil Returns Promptly: If you made no sales, you still have to file. A Nil return takes only two minutes but saves you ₹20 every single day in penalties.

Frequently Asked Questions

What is the GSTR-1 due date?
For monthly filers, the GSTR-1 due date is the 11th of the following month. For quarterly filers (QRMP scheme), it is the 13th of the month following the end of the quarter.

What is the GSTR-3B due date?
For monthly filers, the GSTR-3B due date is the 20th of the following month. For quarterly filers, it is the 22nd or 24th of the month following the quarter, depending on your state.

What is the due date for GST return filing in 2026?
There are multiple due dates depending on your return type. Generally, monthly sales (GSTR-1) are due on the 11th, and monthly tax payments (GSTR-3B) are due on the 20th of every month.

What is the late fee for delayed GST return filing?
The late fee is typically ₹50 per day of delay. If it is a Nil return (no business activity), the late fee is reduced to ₹20 per day.

What is the difference between GSTR-1 and GSTR-3B?
GSTR-1 is a statement of all your outward supplies (sales), showing the invoices you issued. GSTR-3B is a summary return where you declare your total tax liability, claim Input Tax Credit (ITC), and actually pay the tax.

Who files CMP-08?
CMP-08 is filed by businesses registered under the GST Composition Scheme. It is a quarterly statement-cum-challan to declare details or pay tax.

What happens if I miss the GST return due date?
If you miss the due date, you will incur a daily late fee. Additionally, if you have outstanding tax to pay, you will be charged 18% per annum interest on the tax amount.

How can I calculate GST late fee?
You can calculate your exact penalty by multiplying the number of days delayed by ₹50 (or ₹20 for Nil returns) and adding 18% interest on the unpaid tax. You can also use the free KaroTools GST Late Fee Calculator to do the math automatically.