gstr 1

GSTR-1 Return Filing: Due Date, Format, Process, and Rules (2026)

Introduction

GSTR-1 is one of the most important GST returns for registered taxpayers. It contains details of outward supplies made during a tax period and forms the basis for Input Tax Credit (ITC) available to recipients.

Timely and accurate filing of GSTR-1 helps businesses maintain compliance, enables customers to claim ITC, and reduces the chances of notices due to mismatches between GSTR-1 and GSTR-3B.

Whether you are a trader, manufacturer, service provider, exporter, or e-commerce seller, understanding the GSTR-1 filing process is essential for smooth GST compliance.

What is GSTR-1?

GSTR-1 is a statement of outward supplies filed by registered taxpayers under GST containing invoice-wise details of sales and supplies made during a tax period.

It includes:

B2B supplies.
B2C supplies.
Export supplies.
Credit notes.
Debit notes.
Advances received.
HSN-wise summary.

Purpose of GSTR-1

The primary purpose of GSTR-1 is to:

Report outward supplies.
Determine tax liability.
Enable ITC for recipients.
Ensure transparency under GST.
Facilitate reconciliation.

Importance of GSTR-1

Accurate filing of GSTR-1 helps:

Avoid mismatches.
Ensure timely ITC flow to customers.
Reduce departmental notices.
Maintain compliance ratings.
Support GST audits and reconciliations.

Legal Provisions

GSTR-1 is prescribed under:

Section 37 of the CGST Act, 2017.
CGST Rules, 2017.
Notifications issued by CBIC.

Who Needs to File GSTR-1?

Generally, every regular registered taxpayer making outward supplies is required to file GSTR-1.

Regular Taxpayers

Businesses registered under the normal scheme must file GSTR-1.

Examples:

Traders.
Manufacturers.
Service providers.
E-commerce sellers.

Monthly Filers

Taxpayers not covered under QRMP are required to file GSTR-1 every month.

QRMP Taxpayers

Taxpayers opting for the QRMP Scheme can file GSTR-1 quarterly.

Exporters

Exporters must disclose:

Export invoices.
LUT supplies.
Payment of IGST, if applicable.

SEZ Suppliers

Supplies made to SEZ units or developers are reported in GSTR-1.

Exceptions

The following persons are generally not required to file GSTR-1:

Composition taxpayers.
Input Service Distributors (ISD).
TDS deductors.
TCS collectors.
Non-resident taxable persons filing GSTR-5.
Persons liable to deduct tax under Section 51.

Applicability of GSTR-1

Turnover Criteria

GSTR-1 applies to all regular taxpayers irrespective of turnover.

The frequency of filing depends upon:

Monthly filing.
Quarterly filing under QRMP.

Monthly Filing

Taxpayers not opting for QRMP generally file GSTR-1 every month.

Quarterly Filing

Eligible taxpayers under QRMP can furnish GSTR-1 quarterly.

Businesses Required to File

The return is applicable to:

Manufacturers.
Wholesalers.
Retailers.
Service providers.
Exporters.
E-commerce operators (where applicable).
MSMEs.
Startups.

Information Required in GSTR-1

GSTR-1 contains details of outward supplies and related transactions.

B2B Supplies

Invoice-wise details of supplies made to registered persons.

Information Required

GSTIN of recipient.
Invoice number.
Invoice date.
Taxable value.
GST rate.
Tax amount.

B2C Supplies

Details of supplies made to unregistered persons.

These are reported under:

B2C Large.
B2C Other.

Export Supplies

Information includes:

Shipping bill details.
Port code.
Invoice details.
Tax payment status.

Credit Notes and Debit Notes

Adjustments relating to:

Sales returns.
Price revisions.
Corrections.

must be reported.

HSN-wise Summary

The HSN summary contains:

HSN code.
Description.
Quantity.
Unit Quantity Code (UQC).
Taxable value.
Tax amount.

Tax Liability Details

GSTR-1 forms the basis for tax liability reported in GSTR-3B.

Therefore, reconciliation between both returns is extremely important.

GSTR-1 Format Explained

GSTR-1 contains multiple tables for reporting various outward supplies.

Table 4 – B2B Invoices

Contains invoice-wise details of supplies to registered persons.

Table 5 – B2C Large Invoices

Includes interstate supplies exceeding prescribed limits to unregistered persons.

Table 6 – Exports

Reports:

Export invoices.
SEZ supplies.
Deemed exports.

Table 7 – B2C Other Supplies

Contains supplies made to unregistered persons not covered under B2C Large.

Table 9 – Amendments

Used for correction of:

B2B invoices.
B2C invoices.
Credit notes.
Debit notes.

Table 10 – Advances

Reports:

Advances received.
Adjustments against advances.

Table 12 – HSN-wise Summary

Contains:

HSN codes.
UQC details.
Quantity.
Taxable value.

Table 13 – Documents Issued

Reports:

Tax invoices.
Debit notes.
Credit notes.
Revised invoices.
Receipt vouchers.

Why Accurate GSTR-1 Filing is Important

Incorrect invoice reporting may lead to:

GSTR-1 and GSTR-3B mismatch.
ITC denial to recipients.
Departmental notices.
Reconciliation issues.
Additional compliance costs.

Businesses should therefore ensure:

Proper invoice reporting.
Correct GST rates.
Accurate HSN codes.
Timely filing.
Reconciliation with books of accounts.

Key Takeaway

GSTR-1 is the backbone of GST compliance for outward supplies. Correct and timely filing ensures smooth ITC flow, minimizes mismatches, and helps businesses maintain healthy GST compliance.

How to File GSTR-1 Online?

GSTR-1 can be filed online through the GST portal by reporting outward supplies and submitting the return using DSC or EVC.

Timely filing ensures smooth Input Tax Credit (ITC) flow to customers and helps avoid late fees and notices.

Step 1: Login to GST Portal

Visit:

www.gst.gov.in

Username
Password
Captcha code

Step 2: Navigate to Returns Dashboard

Go to:

Services → Returns → Returns Dashboard

Select:

Financial Year
Return Filing Period

Choose:

GSTR-1 – Details of Outward Supplies

Step 3: Enter Invoice Details

Report:

B2B Supplies

Invoice-wise details of sales made to registered persons.

B2C Supplies

Sales made to unregistered persons.

Export Supplies

Export invoices and SEZ transactions.

Credit Notes and Debit Notes

Adjustments and amendments.

HSN-wise Summary

HSN code
Quantity
UQC
Taxable value

Step 4: Verify Outward Supplies

Cross-check:

Invoice numbers.
GSTIN of recipients.
Tax rates.
Taxable values.

Reconcile with:

Books of accounts.
Sales register.

Step 5: Submit and File

After verification:

Click Submit.
File using:
- Digital Signature Certificate (DSC), or
- Electronic Verification Code (EVC).

An ARN (Acknowledgement Reference Number) is generated after successful filing.

GSTR-1 Due Date (2026)

The due date depends upon whether the taxpayer is a monthly filer or a QRMP taxpayer.

Monthly Filing Due Date

Monthly GSTR-1 is generally due on:

11th of the succeeding month

Example

For April 2026:

Due date:

11 May 2026

Quarterly Filing Under QRMP Scheme

Quarterly GSTR-1 is generally due on:

13th of the month following the quarter

Example

Quarter:

April–June 2026

Due Date:

13 July 2026

Latest Notifications

Due dates are subject to:

Government notifications.
CBIC circulars.
Special extensions, if announced.

Businesses should regularly monitor updates.

GSTR-1 Under QRMP Scheme

The Quarterly Return Monthly Payment (QRMP) Scheme allows eligible taxpayers to file GSTR-1 quarterly while paying taxes monthly.

Eligibility

Taxpayers having aggregate turnover up to ₹5 crore can opt for QRMP.

Benefits of QRMP

Reduced Compliance Burden

Quarterly return filing minimizes workload.

Better Cash Flow Planning

Monthly tax payment with quarterly reporting.

Suitable for MSMEs

Helps small businesses simplify compliance.

Quarterly Filing Mechanism

Taxpayers file:

GSTR-1 quarterly.
GSTR-3B quarterly.

Taxes are paid monthly using:

Fixed Sum Method.
Self-Assessment Method.

Nil GSTR-1 Return

A Nil GSTR-1 can be filed when no outward supplies are made during the tax period.

Who Can File Nil GSTR-1?

Taxpayers having:

No sales.
No exports.
No debit notes.
No credit notes.

during the period.

Procedure

Login to GST portal.
Select GSTR-1.
Choose "Nil Return".
Verify and file using EVC or DSC.

GSTR-1 Amendment Process

Mistakes can be corrected through amendment tables in subsequent returns.

Common Amendments

Invoice Corrections

Incorrect:

GSTIN
Invoice value
Tax amount

can be amended.

Credit Notes and Debit Notes

Adjustments can be made through amendment tables.

Reporting in Subsequent Returns

GSTR-1 cannot be revised directly.

Corrections are made in future periods.

Amendment Tables

Generally used tables include:

Table 9A
Table 9B
Table 9C

Late Fees and Penalties for GSTR-1

Failure to file GSTR-1 on time attracts late fees and compliance consequences.

Late Fees

Late fee is prescribed under Section 47 of the CGST Act.

Late fees are generally levied:

Under CGST.
Under SGST.

subject to maximum limits prescribed through notifications.

Interest Implications

Though GSTR-1 itself is a statement of outward supplies, delayed reporting may affect:

Tax payment.
ITC flow.
Reconciliations.

Consequences of Non-Filing

Non-filing may result in:

Late fees.
Notices from department.
Blocking of subsequent returns.
ITC issues for customers.
Scrutiny proceedings.

Common Errors While Filing GSTR-1

Incorrect GSTIN

Wrong GSTIN may result in:

ITC denial to customers.
Reconciliation issues.

Invoice Mismatches

Differences between:

Sales register.
GSTR-1.
GSTR-3B.

often trigger notices.

Wrong HSN Codes

Incorrect HSN reporting can create classification disputes.

Missing Amendments

Failure to amend errors timely leads to persistent mismatches.

Tax Rate Errors

Applying incorrect GST rates may cause:

Short payment.
Demand notices.
Interest liability.

Duplicate Invoices

Duplicate reporting can inflate turnover and tax liability.

Benefits of Timely GSTR-1 Filing

For Businesses

Timely filing ensures:

Better compliance.
Reduced notices.
Improved credibility.

For Customers

Accurate GSTR-1 enables recipients to claim ITC smoothly.

Better Cash Flow Management

Timely compliance prevents disputes and unnecessary tax exposure.

Improved Vendor Relationships

Customers prefer vendors who file returns regularly.

Difference Between GSTR-1 and GSTR-3B

Basis	GSTR-1	GSTR-3B
Nature	Statement of outward supplies	Summary return
Purpose	Report sales	Pay GST liability
Invoice Details	Yes	No
ITC Reporting	No	Yes
Frequency	Monthly/Quarterly	Monthly/Quarterly
Legal Provision	Section 37	Section 39
Tax Payment	No	Yes
Amendments	Allowed in subsequent returns	Through adjustments

Latest GSTR-1 Updates (2026)

E-Invoicing Integration

Invoice data generated through e-invoicing is increasingly auto-populated into GSTR-1.

QRMP Enhancements

The QRMP scheme continues to simplify compliance for MSMEs.

AI-Based Scrutiny

Authorities are using analytics to identify:

GSTR-1 vs GSTR-3B mismatches.
HSN inconsistencies.
Invoice irregularities.

Reconciliation Focus

Businesses are expected to maintain consistency between:

Books of accounts.
E-invoices.
GSTR-1.
GSTR-3B.

Departmental Analytics

Tax authorities are increasingly relying on:

AI tools.
Data analytics.
Automated mismatch detection.

Best Practices for Filing GSTR-1

Reconcile sales register before filing.
Verify GSTIN and invoice details.
Match GSTR-1 with GSTR-3B.
Review HSN codes.
File within due dates.
Amend mistakes promptly.

Key Takeaways

GSTR-1 is governed by Section 37 of the CGST Act, 2017.
It contains invoice-wise outward supply details.
Monthly due date is generally the 11th of the next month.
QRMP taxpayers file quarterly by the 13th of the month following the quarter.
GSTR-1 cannot be revised directly.
Timely filing ensures smooth ITC flow to customers.
Reconciliation with GSTR-3B is essential.
Incorrect reporting may lead to notices and scrutiny.

Conclusion

GSTR-1 is one of the most important returns under the GST framework because it forms the basis for Input Tax Credit available to recipients and helps the department monitor outward supplies. Timely and accurate filing reduces the risk of mismatches, improves customer relationships, and strengthens overall GST compliance.

Businesses should regularly reconcile invoices with books of accounts, ensure proper HSN reporting, and promptly rectify errors through amendment tables. With increasing use of AI-based analytics and automated scrutiny mechanisms, maintaining accurate GSTR-1 data has become more important than ever.

Professional assistance can help businesses simplify return filing and avoid costly mistakes.

Frequently Asked Questions (FAQs)

1. What is GSTR-1?

GSTR-1 is a statement of outward supplies filed by registered taxpayers under GST. It contains invoice-wise details of sales, debit notes, credit notes, exports, and HSN-wise summaries.

2. Who is required to file GSTR-1?

All regular registered taxpayers making outward supplies are generally required to file GSTR-1. Composition taxpayers and certain special category taxpayers are exempt.

3. What is the due date for GSTR-1?

Monthly filers: 11th of the succeeding month.
QRMP taxpayers: 13th of the month following the quarter.

4. Is GSTR-1 mandatory?

Yes. Regular taxpayers making taxable supplies are required to file GSTR-1 under Section 37 of the CGST Act, 2017.

5. Can GSTR-1 be revised?

No. GSTR-1 cannot be revised directly. Errors can be corrected through amendment tables in subsequent returns.

6. Can Nil GSTR-1 be filed?

Yes. A Nil GSTR-1 can be filed if there are no outward supplies during the tax period.

7. What is the QRMP Scheme?

The Quarterly Return Monthly Payment (QRMP) Scheme allows eligible taxpayers with turnover up to ₹5 crore to file returns quarterly while paying taxes monthly.

8. What details are reported in GSTR-1?

GSTR-1 includes:

B2B invoices.
B2C supplies.
Export invoices.
Credit notes.
Debit notes.
HSN summary.
Advances received.

9. What happens if GSTR-1 is not filed?

Non-filing may result in:

Late fees.
Departmental notices.
ITC blockage for recipients.
Scrutiny proceedings.

10. Can GSTR-1 be filed after the due date?

Yes, but late fees and compliance consequences may apply.

11. Is GSTR-1 required for service providers?

Yes. Service providers registered under the regular GST scheme are generally required to file GSTR-1.

12. How do I amend invoice errors in GSTR-1?

Corrections are reported through amendment tables in subsequent tax periods.

13. What is the difference between GSTR-1 and GSTR-3B?

GSTR-1 reports outward supplies invoice-wise, whereas GSTR-3B is a summary return used for tax payment and ITC reporting.

14. Does GSTR-1 affect customer ITC?

Yes. Incorrect or delayed filing may impact Input Tax Credit available to customers.

15. How can businesses avoid GSTR-1 notices?

Businesses should:

Reconcile sales registers.
Match GSTR-1 with GSTR-3B.
Use correct GSTIN and HSN codes.
File returns on time.

Frequently Asked Questions

Yes, filing GSTR 1 is mandatory even if there were no sales during a month/quarter. In this case, you have to file Nil GSTR-1.

You can upload invoices anytime. It is highly advised that you upload invoices at regular intervals during the month to avoid bulk upload at the time of filing a return. This is because bulk upload takes a lot of time.

After uploading bills you can make changes multiple times. There is no restriction on changing invoices after uploading them. But you can change an invoice only before submitting a return. Once submitted, the numbers are frozen.

Yes, you can file the GSTR-1 even after the due date. However, you have to pay a late fee based on the delayed number of days.

You have to report all the sales detail in GSTR-1, whereas you have to report summarised figures of sales, ITC claimed, and net tax payable in GSTR-3B return.

No, with effect from 1st January 2022, you have to file GSTR-1 before filing the GSTR-3B return.

You should not file GSTR-1. However, you have to use Form CMP-08 to make tax payments on a quarterly basis.

GSTR-1 is a return where details of sales are filed with the government. Hence, there is no need to pay tax after filing this return. However, you have to pay the tax due while filing GSTR-3B.

You need to continue filing GSTR-1 on a quarterly basis and the GSTR-3B will also need to be filed on a quarterly basis with monthly tax payments. For more information about the QRMP scheme, read our article on “All about the QRMP scheme.”

You can upload the invoices related to the first two months of the quarter using the Invoice Furnishing Facility (IFF) and last month’s invoices in the quarterly GSTR-1.

Yes, you can make amendments to an already filed GSTR-1 of a particular tax period by declaring the amended details in the return.

For example, Mr X of Kerala has sold goods to Mr Y of Karnataka for Rs. 1,00,000 on 30th December 2023 and declared in the GSTR-1 of December 2023. Now he realised that he made a mistake in the date of the invoice, so he can make an amended invoice with the correct invoice date i.e., 16th December 2023. This amended invoice must have been shown in the GSTR-1 of January 2024.

The ‘Revised date’ to be mentioned in an amended invoice must be not later than the last date of the original invoice tax period.

For example, if an original invoice dated 12th March 2024 is being amended in April 2024 then the revised invoice date cannot be later than 31st March 2023.

The following details cannot be amended at Invoice level :

The Customer GSTIN
Changing a tax invoice to a bill of supply
The following with respect to Export Invoices cannot be amended: a) Shipping Bill Date/Bill of Export Date b) Type of Export- With/Without payment
The following with respect to Credit Debit Notes cannot be amended:
- Receiver/Customer GSTIN. However you may amend & link any other invoice for the same GSTIN.
- Place of Supply
- Reverse charge applicable Reason: Since the above details are based on the original Invoice which it Is linked to, Hence these details must match with the details of the linked Invoice.
If the receiver of goods has taken action on the invoices i.e. accepted or modified and the supplier accepts such modifications in GSTR-1A, he will not be allowed to amend those invoices. The reason is that those invoices will automatically get reflected in the GSTR-1 of the supplier in the month of such acceptance under the relevant amendments table. The following details cannot be amended at a summary level
- Nil Rated
- HSN summary of Outward supplies
- Cannot add a new place of supply

Note: However, you can replace the existing place of supply with another place of supply with some limitations. Refer to the examples given below.

With respect to Place of Supply, note the following:

You can amend the original place of supply for a transaction.
You cannot add any new place of supply to a transaction.

Let us understand the above with the following scenarios:

Nature	Place of supply	Rate of Tax	Taxable Value	Amendment
Original	Kerala	18%	10000	Allowed
Amended To	Karnataka	18%	10000	Allowed

Original	Kerala	28%	50000	Allowed
Amended To	Karnataka	18%	50000	Allowed

Original	Karnataka	5%	10000	Allowed
Original	Karnataka	12%	20000
Amended To	Karnataka	18%	30000

Original	Kerala	18%	60000	Allowed
Amended To	Karnataka	28%	20000
Amended To	Karnataka	12%	40000

Original	Kerala	18%	60000	Not Allowed
Original	Kerala	12%	40000
Amended To	Karnataka	28%	50000
Amended To	Kerala	12%	50000

We can see that in all those cases where the original place of supply was amended from Kerala to Karnataka (whether or not there was a change in tax rates or invoicing), the amendment is allowed.

But in the last case where in addition to Kerala, Karnataka is also added as a place of supply (irrespective of change in tax rates or invoicing) amendment does not hold good

Declare the amended invoices or details in the tax period in which the amendment takes place as follows:

Sl. no.	Type of Amendment	Explanation
1	B2B Amendments (9A)	Amendments made in the invoices already issued earlier must be reported here. These are the invoices for taxable supplies made to registered taxpayers including supplies made to SEZ/ SEZ Developers with or without payment of taxes and deemed exports.
2	B2C Large Amendments (9A)	Amendments in the original invoices already issued must be mentioned here These reflect original invoices issued for taxable outward supplies made to unregistered taxpayers where 1. Supply is made interstate and 2. Total invoice value is more than Rs 2,50,000/-
3	Credit/Debit Notes (Registered) Amendments(9C)	Credit or debit note amended against already issued Credit or debit note reported under B2B (i.e where supply is made to registered taxpayer), will be reported here.
4	Credit Debit Note (Unregistered) Amendments(9C)	Amended Credit or debit note issued against original Credit or debit note reported under B2C Large and Export Invoices section, will be reported here.
5	Export Invoices Amendments(9A)	Amended invoices issued against already issued original invoices must be reported here. Export invoices includes 1. Export under bond/LUT-If you are exporting under bond or letter of undertaking and not paying IGST. 2. Export with IGST-If you are exporting without furnishing bond/letter of supply and paying IGST on such supply (It excludes deemed exports & supply to SEZ)
6	B2C Others Amendments (10)	Amendments made in the invoices already issued earlier must be reported here. These are all those invoices not covered under 1. B2B 2. B2C Large 3. Exports
7	Advances Received (Tax Liability) Amendments (11(2))	Any amendments made to the advances received in previous tax periods has to be declared here.
8	Adjustment of Advances Amendments (11(2))	Any amendments made to the advances adjusted in previous tax periods have to be declared here.
9	Amendment to sales through e-commerce operator u/s 52 and 9(5) of the CGST Act reported by suppliers	Any amendments made to the e-commerce sales of previous tax periods have to be declared here.
10	Amendment to sales through e-commerce operator u/s 9(5) of the CGST Act reported by e-commerce operators	Any amendments made to the specific sales u/s 9(5) of previous tax periods have to be declared here.

Details to be mentioned in GSTR-1

Guide to file GSTR-1 using Clear GST Software

How to file GSTR-1 on GST Portal

How to file GSTR-1 on Tally