GST Filing Help Guide for myBillBook Users

Written By Team Flobiz

Last updated 7 months ago

Overview

Filing GST returns can be challenging, but most errors are preventable with proper data preparation. This guide helps you identify and fix common issues before uploading your GST returns to the portal, saving you time and reducing filing errors.

Before You Start

Important: Before uploading your JSON file directly to the GST Portal, we strongly recommend downloading your GSTR-1 (Sales) Excel file from myBillBook and reviewing it for common issues outlined below.

Common GST Filing Issues & Solutions

🔁 HSN Code Related Issues

HSN (Harmonized System of Nomenclature) codes are critical for GST filing. The GST Portal will reject your file if there are issues with HSN codes.

Duplicate HSN Entries

  • Issue: Same HSN code with identical tax rates listed multiple times

  • Solution: Consolidate duplicate entries into single rows and update quantities accordingly

  • Prevention: Review your HSN summary before filing

Incorrect HSN Code Length

  • Issue: Wrong number of digits in HSN codes

  • Correct Format:

    • 4 digits if your annual turnover is below ₹5 crore

    • 6 or 8 digits if your annual turnover is above ₹5 crore

  • Solution: Update HSN codes to match the required digit format based on your turnover

Invalid HSN Codes

  • Issue: HSN codes that don't exist in the official HSN directory

  • Solution: Verify HSN codes using the official GST HSN/SAC search tool: https://services.gst.gov.in/services/searchhsnsac

  • Special Note: HSN codes starting with "99" are service items and require special handling

🔢 GST Number Related Issues

Invalid or Blocked GSTIN

  • Issue: Party GSTIN is incorrect, inactive, cancelled, or blocked

  • Common Causes:

    • Typing errors in GSTIN

    • Using outdated or cancelled GSTINs

  • Solution: Verify all GSTINs on the GST Portal and update with correct, active numbers

Missing Place of Supply

  • Issue: Place of Supply field is empty, especially in B2C invoices

  • Solution:

    • Add Place of Supply in B2B, B2C, and B2CS sheets

    • For B2C cash sales invoices, use your own state as Place of Supply

🧾 Invoice Number Format Issues

Incorrect Invoice Format

  • Issue: Invalid characters or formatting in invoice numbers

  • GST Rules: Only the following are allowed in invoice numbers:

    • Forward slash (/)

    • Hyphen (-)

    • Plain text and numbers

  • Common Mistakes to Avoid:

    • Special characters (@, #, *, etc.)

    • Extra spaces

    • Leading zeros (e.g., 001)

  • Solution: Clean up invoice numbers to remove invalid characters and formatting

Step-by-Step Filing Process

Step 1: Download and Review Your GSTR-1 Excel File

  1. Download your GSTR-1 Excel file from myBillBook

  2. Review all sheets (B2B, B2C, B2CS) for the issues mentioned above

  3. Make necessary corrections

Step 2: Use GST Offline Tool for Validation

  1. Download GST Offline Tool: https://www.gst.gov.in/download/returns

  2. Launch the Tool: Open GST Offline Tool from your desktop

  3. Create New Return: Click "New" and select "GSTR-1"

  4. Enter Details:

    • GSTIN

    • Financial Year

    • Return Period

    • SEZ Taxpayer status (Yes/No)

    • Quarterly Filer status (Yes/No)

    • Turnover above ₹5 crore (Yes/No)

  5. Click "Proceed" and confirm details

  6. Import Excel File: Select "Import Files" → "Import Excel" → Upload your corrected GSTR-1 file

  7. Verify Data: Click "View Summary" to review uploaded data

  8. Generate JSON: Click "Generate File" and download the JSON file

Step 3: Upload to GST Portal

Upload the validated JSON file to the GST Portal for final submission.

Known Limitations After Using GST Offline Tool

Even after successful validation, you may encounter these issues on the GST Portal:

HSN Wise Summary Not Captured

  • Issue: HSN summary for B2B and B2C may not appear automatically

  • Solution: Manually enter/update HSN details using the "Table" option on GST Portal

Document Issued Dates Missing

  • Issue: Invoice issue dates may not transfer properly

  • Solution: Manually update dates using the "Table" option on GST Portal

Prevention Tips

  1. Regular Data Validation: Periodically review your invoice data for accuracy

  2. HSN Code Maintenance: Keep an updated list of valid HSN codes for your products/services

  3. GSTIN Verification: Regularly verify customer GSTINs, especially for new clients

  4. Invoice Format Standards: Establish and follow consistent invoice numbering formats

  5. User Training: Ensure all users understand GST data entry requirements

Quick Reference Checklist

Before filing your GST return, ensure:

  • No duplicate HSN entries

  • Correct HSN code length (4, 6, or 8 digits based on turnover)

  • All HSN codes are valid

  • All GSTINs are active and correct

  • Place of Supply is specified for all invoices

  • Invoice numbers use only allowed characters (/, -, plain text)

  • No leading zeros or extra spaces in invoice numbers

Following this checklist will help ensure smooth GST filing and reduce the likelihood of errors or rejections from the GST Portal.