Monthly GST Compliance & Filing

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Monthly GST Compliance & Filing

Department: Accounts / Finance

Status: Active

Created On: 25 May 2026

Purpose

This SOP defines the step-by-step procedure for preparing, verifying, reconciling, and filing monthly GST returns including GSTR-1, GSTR-2B reconciliation, and GSTR-3B filing. The purpose is to ensure timely compliance, avoid penalties, maintain proper Input Tax Credit records, and keep management informed about filing status.

Phase 1: Sales Data Preparation for GSTR-1

Step 1.1: Extract Sales Data

Download the sales register or invoice ledger from the accounting software for the previous month. Ensure the report includes invoice number, invoice date, customer name, GSTIN, taxable value, CGST, SGST, IGST, and total invoice value.

Sub-points / Checks

  • Confirm report is for the correct month.
  • Ensure cancelled invoices are clearly marked.
  • Ensure credit notes and debit notes are included separately.
  • File name should include month and year.

Step 1.2: Verify Invoice Details

Check all sales invoices to ensure GST details are correct before uploading to the GST portal.

Sub-points / Checks

  • GSTIN should be valid.
  • Invoice numbers should be sequential.
  • CGST + SGST should be used for intra-state sales.
  • IGST should be used for inter-state sales.
  • Taxable value should match invoice total.

Step 1.3: Separate B2B and B2C Invoices

Separate invoices into Business-to-Business and Business-to-Consumer categories as required for GSTR-1 filing.

Sub-points / Checks

  • B2B invoices must have valid GSTIN.
  • B2C invoices should not be uploaded as B2B.
  • Export invoices should be marked separately if applicable.

Phase 2: GSTR-1 Upload and Filing

Step 2.1: Login to GST Portal

Login to the GST portal using the client GST credentials and open the returns dashboard.

Sub-points / Checks

  • Verify GSTIN before proceeding.
  • Confirm selected month is correct.
  • Do not proceed if portal shows previous pending alerts without informing manager.

Step 2.2: Upload B2B and B2C Details

Upload or manually enter invoice details into GSTR-1 based on the prepared sales register.

Sub-points / Checks

  • B2B details should be uploaded in correct table.
  • B2C summary should match sales register.
  • Credit notes should be linked to original invoices wherever required.
  • Export invoices should be entered separately if applicable.

Step 2.3: Generate and Verify GSTR-1 Summary

Generate the GSTR-1 summary from the GST portal and compare it with the internal sales register.

Sub-points / Checks

  • Taxable value should match internal sales register.
  • CGST, SGST, and IGST totals should match.
  • Any mismatch should be corrected before filing.

Step 2.4: Submit and File GSTR-1

After final approval, submit and file GSTR-1 using EVC or DSC.

Sub-points / Checks

  • Do not file without manager approval.
  • Save ARN after filing.
  • Confirm return status shows filed.

Phase 3: GSTR-2B and Purchase Reconciliation

Step 3.1: Download GSTR-2B

Download the auto-generated GSTR-2B statement from the GST portal after the 14th of the month.

Sub-points / Checks

  • Download only after GSTR-2B is generated.
  • Confirm month and GSTIN.
  • Save file with proper naming format.

Step 3.2: Reconcile Purchase Register with GSTR-2B

Compare purchase register entries with GSTR-2B to identify eligible ITC, missing invoices, and mismatches.

Sub-points / Checks

  • Invoice number should match.
  • Supplier GSTIN should match.
  • Taxable value and tax amount should match.
  • Missing invoices should be followed up with vendors.
  • ITC not appearing in GSTR-2B should not be claimed without approval.

Step 3.3: Prepare ITC Summary

Prepare final Input Tax Credit summary based on eligible invoices from GSTR-2B reconciliation.

Sub-points / Checks

  • Eligible ITC should match GSTR-2B.
  • Ineligible ITC should not be claimed.
  • Reverse charge entries should be verified separately.

Phase 4: GSTR-3B Tax Calculation and Filing

Step 4.1: Calculate Output Tax Liability

Calculate total output tax liability based on filed GSTR-1 and sales register.

Sub-points / Checks

  • Output tax should match sales register.
  • Inter-state and intra-state tax should be properly separated.
  • Any adjustment should be documented.

Step 4.2: Calculate Net GST Payable

Calculate net GST payable after adjusting eligible Input Tax Credit. Formula: Net GST Payable = Output Tax Liability - Eligible Input Tax Credit.

Sub-points / Checks

  • ITC should be claimed only if eligible.
  • Cash payment should be calculated correctly.
  • Interest or late fee should be added if applicable.

Step 4.3: Prepare and File GSTR-3B

Prepare GSTR-3B on the GST portal, verify all tables, make payment if required, and file the return.

Sub-points / Checks

  • Table 3.1 should match outward supply data.
  • Table 4 should match ITC summary.
  • Tax payment should be completed before filing.
  • Return status should show filed.

Phase 5: Post-Filing Documentation

Step 5.1: Download Filing Acknowledgements

Download filing acknowledgement receipts and ARN details for GSTR-1 and GSTR-3B.

Sub-points / Checks

  • ARN should be clearly visible.
  • Filing date should be recorded.
  • Files should be saved in correct client folder.

Step 5.2: Update GST Compliance Tracker

Update the internal GST compliance tracker with return filing date, ARN, tax paid, challan details, and remarks.

Sub-points / Checks

  • Tracker should be updated on the same day.
  • Tax paid amount should match challan.
  • Pending issues should be noted in remarks.

Step 5.3: Send Filing Confirmation to Management

Send a confirmation email or message to management after successful filing of monthly GST returns.

Sub-points / Checks

  • Mention GSTIN and return period.
  • Mention GSTR-1 filing status.
  • Mention GSTR-3B filing status.
  • Mention tax paid if applicable.
This is a system generated SOP document.