GST Filing 2025: Complete Guide for GSTR-1 & GSTR-3B Corrections and Deadlines for Financial Year 2024-2025

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by

Himanshu
in

As the GST filing deadline for the July-September 2025 quarter approaches, businesses must ensure their GSTR-1 and GSTR-3B returns are accurate. This period represents the final opportunity to correct errors from the financial year 2024-2025, particularly for quarterly filers. Filing errors or mismatched entries can lead to complications in annual returns, such as GSTR-9 and GSTR-9C, and potential penalties.

In addition, mandatory GST rate changes effective from September 2nd, 2025, require special attention. Taxpayers now need to report supplies separately based on rates before and after the change, which may require multiple entries for the same HSN code. This guide explains the corrections, reconciliations, and filing steps necessary to comply with GST regulations and avoid errors.

1. Importance of Correcting GST Returns for FY 2024-2025

The July-September quarter filing is critical for businesses to:

  • Correct previously missed or erroneous entries in GSTR-1 and GSTR-3B.
  • Reconcile Input Tax Credit (ITC) utilization and reversals.
  • Align quarterly data with annual returns (GSTR-9 & GSTR-9C).
  • Ensure compliance with updated GST rates effective September 2nd, 2025.

Failing to make these corrections now can create tax liability issues, penalties, and audit complications.

2. Mandatory GST Rate Adjustments and Their Impact

From September 2, 2025, several GST rates were revised for goods and services. Filers need to:

  • Separate entries in GSTR-1 for supplies made before and after the rate change.
  • Ensure accurate calculation of GST for both old and new rates.
  • Prepare multiple HSN code entries if a single code now attracts different rates within the same quarter.

Table 1: Example of HSN Entries for Rate Changes

HSN CodeDescriptionGST Rate Before 2 SeptGST Rate After 2 SeptSeparate Entry Required?
1001Product A12%18%Yes
1002Product B5%12%Yes
1003Product C18%18%No

This separation ensures compliance with updated GST regulations and prevents mismatches during annual reconciliation.

3. GSTR-1 Filing: Key Instructions

GSTR-1 is the return for outward supplies. Key steps to ensure accuracy include:

  • Review previous quarter data for missing invoices or errors.
  • Split entries by GST rate change if applicable.
  • Check HSN summaries to confirm the total taxable value and GST amounts.
  • Verify invoice details: GSTIN, invoice number, and date.

Common GSTR-1 Errors to Avoid

Error TypeImpact on FilingSuggested Correction
Missing invoicesUnderreported salesAdd missing invoices before filing
Incorrect GST rateMismatched tax calculationsSplit entries according to rate change
HSN code mismatchPortal rejection or mismatch alertsCross-check with product list
Duplicate entriesInflated sales & errorsRemove duplicates

4. GSTR-3B Filing: Input Tax Credit (ITC) Reconciliation

GSTR-3B covers the summary of inward and outward supplies and ITC. Key points include:

  • Utilize remaining ITC from FY 2024-2025 before the filing window closes.
  • Reverse ineligible ITC claimed earlier.
  • Reconcile ITC with supplier invoices to prevent portal mismatch errors.
  • Match tax liability and credit utilization to avoid discrepancies in annual filings.

Table 2: ITC Reconciliation Steps

ActionDescription
Check available ITCReview balance from FY 2024-2025
Reverse ineligible ITCAdjust for exempt/non-eligible supplies
Match inward supplies with ITCVerify supplier invoices match claimed ITC
Record remaining ITC utilizationEnsure all eligible credit is claimed before deadline

5. Step-by-Step Filing Action Plan

To comply with GST regulations and meet the November 30th deadline, businesses should follow these steps:

Step 1: Collect Data

  • Gather all invoices from the current quarter and FY 2024-2025.
  • Identify missing, incorrect, or mismatched entries.

Step 2: Update GSTR-1

  • Separate entries affected by GST rate changes.
  • Ensure accuracy in taxable value and GST amount.

Step 3: Review GSTR-3B

  • Reconcile ITC claims and reversals.
  • Ensure the total tax liability aligns with available credit.

Step 4: Verify Portal Mismatches

  • Cross-check error reports on the GST portal.
  • Resolve alerts related to HSN codes or GST amounts.

Step 5: File Before Deadline

  • Complete filing before November 30th, 2025.
  • Maintain records for audit and future reference.

6. Tips for Stress-Free GST Compliance

  1. Maintain Accurate Records: Regular bookkeeping reduces last-minute filing pressure.
  2. Use Accounting Software: Automates reconciliation and reduces errors.
  3. Monitor GST Rate Notifications: Stay updated with government circulars.
  4. Double-Check HSN Codes: Correct codes prevent rejection or mismatch alerts.
  5. Consult Professionals: Seek expert guidance for complex corrections.

7. Benefits of Timely and Accurate Filing

  • Avoid Penalties: Timely corrections prevent late fees and fines.
  • Smooth Annual Filing: Accurate quarterly data simplifies GSTR-9 and GSTR-9C submissions.
  • Financial Accuracy: Proper ITC reconciliation reduces discrepancies in tax liabilities.
  • Compliance Confidence: Ensures business remains audit-ready and GST compliant.

Conclusion

The July-September 2025 GST filing window represents the final opportunity to correct errors from FY 2024-2025. With mandatory GST rate adjustments, multiple HSN entries, and ITC reconciliation requirements, it is essential for businesses to act promptly. Following a structured approach for GSTR-1 and GSTR-3B filing ensures compliance, smooth annual returns, and avoidance of penalties. Timely action now will safeguard your business and maintain accuracy in all GST filings.

Disclaimer

This article is for informational purposes only and does not constitute legal or financial advice. Taxpayers should refer to official GST notifications and consult qualified professionals for specific guidance on GST filing, corrections, and compliance.