Amazon B2CS Converter
Convert Amazon MTR B2C CSV files to GSTR-1 B2CS format instantly with automatic state mapping, tax rate calculation, and data grouping.
Introduction
Selling on Amazon means dealing with hundreds or thousands of B2C transactions every month spread across all Indian states with varying GST rates. When GST filing time comes, you download the MTR (Monthly Tax Report) B2C CSV from Amazon Seller Central, but this format does not match what the GST portal expects for GSTR-1 B2CS filing. The portal requires data grouped by Place of Supply (state) and Tax Rate, with proper state codes, aggregated taxable values, and exact column formatting. Manually converting thousands of rows—checking whether each transaction is interstate (IGST) or intrastate (CGST+SGST+UTGST), mapping state names to official codes, calculating effective tax rates, grouping identical state-rate combinations, and summing taxable values—takes hours and invites errors. This tool automates the entire Amazon MTR B2C to GSTR-1 B2CS conversion process in seconds, all in your browser without uploading sensitive sales data anywhere. Upload your Amazon CSV, click convert, and download a GST portal-ready Excel file with perfectly formatted B2CS data. The tool intelligently handles interstate IGST transactions versus intrastate CGST+SGST combinations, automatically maps all 36 Indian state and UT names to their official numeric codes, calculates effective tax rates from the separate tax columns Amazon provides, groups transactions by state and rate, aggregates taxable values, and generates the exact B2CS Excel format the GST portal accepts—including correct column names, data types, and ordering. You get a clean B2CS sheet ready for direct upload, saving hours of manual work and eliminating copy-paste errors that can cause GST filing rejections. Everything processes locally on your device, so your Amazon sales data never leaves your computer, ensuring complete privacy and security for your business information.
Who Should Use This Tool?
- Amazon sellers filing GSTR-1 monthly or quarterly
- Accountants managing multiple Amazon seller accounts
- E-commerce tax consultants handling GST compliance
- Small business owners selling on Amazon India
- Chartered accountants preparing B2CS returns
- Sellers with high transaction volumes across states
- Anyone converting Amazon MTR B2C to GST format
- Finance teams automating GST data preparation
How This Tool Works
This tool processes Amazon MTR B2C CSV files entirely in your browser using JavaScript, converting them to the GSTR-1 B2CS format required by the GST portal without any server upload. When you upload your Amazon CSV, the tool first parses all rows using the PapaParse library to handle CSV formatting variations and large files efficiently. It identifies key columns like Transaction Date, Invoice Amount, Tax Rate, IGST Rate, CGST Rate, SGST Rate, UTGST Rate, and Ship To State. For each transaction row, the tool determines whether it is an interstate or intrastate sale by checking the IGST Rate column—if IGST is greater than zero, the sale is interstate; otherwise, it calculates the effective tax rate by summing CGST + SGST + UTGST for intrastate sales. The tool then maps the Ship To State name to the official Place of Supply numeric code using a comprehensive lookup table covering all 36 Indian states and union territories, handling common variations in state names. It groups all transactions by the combination of Place of Supply (state code) and Tax Rate, aggregating the taxable values for each unique group. The tool also calculates totals for Cess Amount if present in the Amazon data, though this is rare for most products. After grouping and aggregation, the tool constructs a new dataset in the exact B2CS format specified by the GST portal: Type (always 'OE' for e-commerce), Place Of Supply (state code and name), Applicable % of Tax Rate (always blank for B2CS), Rate (the effective GST rate), Taxable Value (aggregated sum), Cess Amount (typically zero), and E-Commerce GSTIN (Amazon's GSTIN: 29ABCD12345E1Z5). This formatted data is written to a new Excel file using the SheetJS library, creating a sheet named 'B2CS' with proper column headers, numeric formatting, and data types. The Excel file is then downloaded to your device with a clear filename like 'Amazon_B2CS_YYYY-MM-DD.xlsx'. The entire conversion happens client-side in your browser—no data is transmitted to any server—ensuring your Amazon sales data, customer information, and business metrics remain completely private. This approach combines speed, accuracy, privacy, and compliance, turning a tedious multi-hour manual task into a simple one-click operation.
Try Amazon B2CS Converter Now
Use the interactive tool below to get instant results
Amazon MTR B2C to GSTR-1 B2CS Converter
Default GSTIN for Amazon India. Update if needed.
Important Notice
This converter tool is for informational purposes only. Please verify the generated B2CS data before uploading to the GST portal. Ensure your Amazon MTR B2C CSV file contains all required columns with correct data. All data processing happens locally in your browser - no data is uploaded to any server.
What Gets Converted
- ✓ Reads Amazon MTR B2C CSV files
- ✓ Handles interstate (IGST) & intrastate (CGST+SGST)
- ✓ Groups by Place of Supply and Rate
- ✓ Aggregates Taxable Value and Cess
- ✓ Formats for GST portal B2CS upload
Privacy & Security
- ✓ 100% client-side processing
- ✓ No data uploaded to servers
- ✓ Files stay on your device
- ✓ GSTR-1 compliant format
- ✓ Automatic state code mapping
How to Use Amazon B2CS Converter
Download Amazon MTR B2C CSV Report
Log in to Amazon Seller Central and navigate to Reports > Tax Document Library. Select the month you need to file GST for, and download the MTR B2C report in CSV format. This report contains all Business-to-Consumer sales data including transaction dates, invoice amounts, GST breakdowns (IGST, CGST, SGST, UTGST), tax rates, and ship-to state information. Make sure you download the B2C report, not B2B, as they have different structures and the tool is designed specifically for Amazon B2C data.
Upload CSV File to the Tool
Click the upload area or drag and drop your downloaded Amazon MTR B2C CSV file onto the tool. The tool instantly parses the CSV, reading all columns and rows regardless of file size (handles thousands of transactions easily). You will see a preview showing the number of rows detected and key column names like IGST Rate, CGST Rate, Ship To State. All processing happens in your browser—no upload to any server occurs, keeping your sales data completely private on your device.
Convert Data to B2CS Format
Click the "Convert to B2CS" button to process your Amazon data. The tool automatically distinguishes interstate (IGST) from intrastate (CGST+SGST+UTGST) transactions, calculates effective tax rates, maps ship-to state names to official Place of Supply codes, groups transactions by state and tax rate, aggregates taxable values, and formats everything into the exact B2CS structure the GST portal expects. You will see a conversion summary showing input rows, output grouped rows, and total taxable value for verification.
Download GST Portal-Ready Excel File
After conversion completes, click "Download B2CS Excel" to save the file to your device. The Excel file contains a B2CS sheet with all required columns: Type, Place Of Supply, Applicable % of Tax Rate, Rate, Taxable Value, Cess Amount, and E-Commerce GSTIN. This file is ready for direct upload to the GST portal for GSTR-1 filing under the B2CS section (sales to unregistered consumers through e-commerce operators). Open the file to review the grouped data before uploading if needed.
Use Cases for Amazon B2CS Converter
Monthly GSTR-1 Filing for Amazon Sellers
If you sell products on Amazon India, you are required to file GSTR-1 returns monthly (or quarterly if eligible) reporting all your sales. Amazon provides MTR B2C CSV reports with detailed transaction-level data, but the GST portal requires B2CS format with data grouped by state and tax rate. Manually converting hundreds or thousands of transactions is tedious and error-prone. This tool automates the entire conversion process—upload your Amazon CSV, get a GST-ready Excel file in seconds. Saves hours every filing cycle and ensures accuracy in tax rate calculation, state mapping, and data grouping, reducing the risk of filing errors or rejections.
Handling Multi-State Sales with Varying GST Rates
Amazon sellers often ship products across all Indian states, dealing with both interstate IGST sales and intrastate CGST+SGST sales. Different product categories also have different GST rates (5%, 12%, 18%, 28%). The B2CS format requires grouping by both Place of Supply and Tax Rate, meaning a seller shipping to 20 states with 3 different product rate categories could have 60+ grouped rows to calculate and format. This tool handles the complexity automatically—correctly identifying interstate vs intrastate based on IGST presence, calculating effective rates from CGST+SGST+UTGST for intrastate, mapping all 36 state names to codes, grouping by state-rate combinations, and aggregating taxable values accurately.
Accountants Managing Multiple Amazon Seller Clients
Tax consultants and accountants often handle GST filing for multiple Amazon sellers. Each client provides their Amazon MTR B2C CSV every month, and converting each one manually becomes a repetitive, time-consuming task. Using this tool standardizes the conversion process—upload CSV, download B2CS Excel—creating consistency across all client filings. Reduces processing time per client from 30-60 minutes to under 2 minutes. Frees up time for higher-value advisory work while ensuring all clients get accurate, compliant B2CS data ready for GST portal upload. The client-side processing also means sensitive client sales data never leaves your device, maintaining confidentiality.
Verifying and Cross-Checking GST Data Before Filing
Before uploading B2CS data to the GST portal, it is critical to verify the numbers are correct - total taxable value matches expectations, tax rates are accurate, state codes are mapped correctly, and no transactions are missed. After converting with this tool, you can open the generated Excel file and review the grouped B2CS data, comparing totals against your own records or Amazon's summary reports. The conversion summary displayed by the tool (showing input rows, output rows, and total taxable value) provides a quick sanity check. This verification step catches potential issues before submission, avoiding costly amendments or penalty scenarios later.
Seasonal Sellers with Fluctuating Transaction Volumes
Many Amazon sellers experience seasonal spikes - festivals, holidays, sales events - where transaction volumes skyrocket from hundreds to thousands per month. Manually converting Amazon data becomes completely impractical during high-volume periods. This tool scales effortlessly - handles 10 transactions or 10,000 transactions with the same speed and accuracy. During off-peak months, process small datasets quickly; during peak months, convert massive CSVs without bottlenecks. The browser-based processing means performance depends on your device, not server queues, so you get consistent fast results regardless of when you run the conversion.
Key Features
Automatic CSV Parsing
Reads Amazon MTR B2C CSV files with automatic column detection.
Interstate IGST Detection
Identifies interstate sales by checking IGST Rate column presence.
Intrastate Tax Calculation
Calculates effective rate as CGST + SGST + UTGST for intrastate sales.
State Code Mapping
Maps all 36 Indian states and UTs to official Place of Supply codes.
State Name Variations
Handles common variations in state names from Amazon data.
Automatic Grouping
Groups transactions by Place of Supply and Tax Rate automatically.
Taxable Value Aggregation
Sums taxable values for each state-rate group accurately.
Cess Amount Support
Includes Cess Amount aggregation if present in Amazon data.
E-Commerce GSTIN
Automatically includes Amazon's E-Commerce GSTIN in output.
GST Portal Format
Generates exact B2CS format required by GST portal.
Excel Export
Downloads B2CS data as properly formatted Excel file.
Conversion Summary
Shows input rows, output rows, and total taxable value for verification.
Large File Support
Handles thousands of transactions without performance issues.
Client-Side Processing
All processing happens in your browser—no server upload.
Complete Privacy
Your Amazon sales data never leaves your device, ensuring confidentiality.
Frequently Asked Questions
What is the Amazon MTR B2C report and where do I download it?
MTR stands for Monthly Tax Report. The B2C report contains all your Business-to-Consumer sales data from Amazon for a specific month, including transaction dates, invoice amounts, GST breakdowns (IGST, CGST, SGST, UTGST rates), ship-to state, and other details needed for GST filing. To download it, log in to Amazon Seller Central, go to Reports > Tax Document Library, select the month you need, and download the MTR B2C report in CSV format. Make sure you choose B2C, not B2B, as the formats differ and this tool is designed specifically for B2C data structure.
How does the tool distinguish between interstate and intrastate sales?
The tool checks the IGST Rate column in your Amazon MTR B2C CSV. If the IGST Rate is greater than zero, the sale is treated as interstate (buyer in a different state than seller), and the tool uses the IGST Rate as the effective tax rate. If IGST Rate is zero or blank, the sale is intrastate (buyer in same state as seller), and the tool calculates the effective rate by adding CGST Rate + SGST Rate + UTGST Rate. This logic correctly handles both scenarios and ensures accurate tax rate reporting in the B2CS output.
Does the tool map state names to Place of Supply codes automatically?
Yes! The tool includes a comprehensive lookup table mapping all 36 Indian states and union territories to their official numeric Place of Supply codes used by the GST portal (01 for Jammu & Kashmir, 29 for Karnataka, etc.). It reads the Ship To State column from your Amazon CSV and automatically maps the state name to the correct code. The tool also handles common variations in state names (like "Delhi" vs "NCT of Delhi") to ensure accurate mapping even if Amazon uses slightly different naming conventions.
Why is the B2CS file smaller than my original Amazon CSV?
That is expected and correct! Your Amazon MTR B2C CSV contains individual transaction rows—one row per invoice or sale. Depending on your sales volume, this could be hundreds or thousands of rows. The B2CS format required by the GST portal, however, demands grouped and aggregated data—all transactions with the same Place of Supply (state) and Tax Rate must be combined into a single row with the taxable values summed. For example, if you have 200 sales to Karnataka at 18% GST, the tool combines all 200 rows into one B2CS row showing the aggregated taxable value. This grouping is exactly what the GST portal expects and why your output file has far fewer rows than the input.
Can I edit the B2CS Excel file before uploading to the GST portal?
Yes, absolutely! The tool generates a standard Excel file that you can open in Excel, Google Sheets, or any spreadsheet application. Before uploading to the GST portal, you can review the data, verify totals, and make corrections if needed (though the tool is designed to be accurate, manual review is always prudent). Just be careful to maintain the exact column structure and order: Type, Place Of Supply, Applicable % of Tax Rate, Rate, Taxable Value, Cess Amount, E-Commerce GSTIN. The GST portal is strict about format compliance, so avoid changing column names, reordering columns, or deleting mandatory fields. Correcting values is safe; structural changes can cause upload failures.
Is my Amazon sales data uploaded to any server when using this tool?
No! All conversion processing happens entirely in your browser using JavaScript. When you upload your Amazon MTR B2C CSV, the file is read locally on your device, parsed in memory, converted to B2CS format, and the Excel file is generated—all without any data leaving your computer. There is no server upload, no database storage, no logging of your sales data. This client-side processing ensures complete privacy and security for your sensitive business information, transaction details, and customer data. Even we (the tool creators) cannot see your Amazon data. Your files remain 100% private on your device throughout the entire process.