GST RECONCILIATION← GST Knowledge
GST KNOWLEDGE • RETURN FILING

GSTR-1 Common Mistakes: 20 Errors That Can Cause GST Mismatches

Practical error-prevention guide for accountants and businesses filing GSTR-1.

In simple words: This article explains the return from a practical filing perspective—what information belongs in it, which records should support it, how to reconcile it and what can go wrong if the data is reported incorrectly.

1. 1. GSTIN errors

Wrong recipient GSTIN can affect the recipient's purchase records and ITC.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

2. 2. Invoice number/date errors

Maintain a unique document register and reconcile invoice series.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

3. 3. Wrong place of supply

Review state code and interstate/intrastate treatment.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

4. 4. Wrong tax rate or taxable value

Reconcile invoice calculations with the sales ledger.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

5. 5. Credit/debit note errors

Link notes to original documents and avoid duplication.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

6. 6. Export/SEZ classification

Check zero-rated treatment and supporting documents.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

7. 7. HSN/SAC errors

Use the current HSN/SAC requirements applicable to the taxpayer.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

8. 8. Table 13 omission

From the May 2025 return period, Table 13 reporting is mandatory where applicable supplies are reported.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

9. 9. B2C classification errors

Perform state-wise and invoice-value checks.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.

10. 10. Final control

Compare GSTR-1 totals with books and the corresponding GSTR-3B liability.

Practical control: Reconcile the relevant books/records with GST Portal return data before filing and retain the working supporting the figure.
Recommended workflow
Books / RegistersGST Portal dataReconcileReviewFile

Final checklist

Knowledge-purpose disclaimer: This article is for general educational and practical understanding. GST law, rules, notifications, circulars, portal functionality and filing procedures can change. Verify the provisions and procedures applicable to the relevant tax period and the facts of the transaction before taking a final tax position.

→ Open GST ITC Reconciliation Tool