GSTR-1 Offline Tool

How to prepare GSTR-1 offline using the official Excel format

By gstr2bmatch.in Editorial Team · Updated 10 October 2026 · 4 min read

Entering hundreds of invoices manually on the GST portal is slow and prone to errors. GSTN provides a free Returns Offline Tool that lets you prepare your sales data in an Excel workbook and upload it as a single JSON file. The tool must be used before the GSTR-1 due date (the 11th for monthly filers, the 13th for quarterly filers).

Most accounting software exports GSTR-1 data directly. If you manage sales in a custom system or prefer to review everything in a spreadsheet before filing, the official GST Returns Offline Tool is the safest route. It uses a structured Excel workbook with separate sheets for each section of the return.

The official GSTR-1 Excel layout

The GST portal provides a zip file containing the offline utility application and a standard Microsoft Excel workbook named GSTR_Excel_Utility. This workbook is the only format the offline tool accepts.

The workbook contains separate tabs for each reporting table:

  • B2B: Taxable outward supplies to registered persons.
  • B2CL: Large inter-state supplies to unregistered persons.
  • B2CS: Small inter-state supplies and intra-state supplies to unregistered persons.
  • CDNR & CDNUR: Credit and debit notes to registered and unregistered persons.
  • HSN & DOCS: HSN-wise summary and details of documents issued.

Common mistake: Adding or renaming columns in the template. The offline tool reads specific columns in a specific order. If you change the header names or insert calculation columns in the middle of the sheet, the JSON generation will fail.

How to upload the offline data

Once your Excel file is ready, you cannot upload the `.xlsx` file directly to the GST portal. You must convert it into a JSON file first.

Step 1: Fill Excel → Step 2: Import to Offline Tool → Step 3: Generate JSON → Step 4: Upload JSON to Portal
  1. Open the GST Offline Tool application on your computer.
  2. Select Upload new invoice/other data for return.
  3. Choose GSTR-1, enter your GSTIN and the tax period, and click Proceed.
  4. Click Import Files and select your completed Excel workbook. The tool will scan for errors.
  5. Click Generate JSON. Save the file to your computer.
  6. Log in to the GST portal. Go to Services → Returns → Returns Dashboard.
  7. Select the period and click PREPARE OFFLINE on the GSTR-1 tile.
  8. Upload the JSON file.

Reviewing the upload

The portal takes a few minutes to process the JSON. Once processed, click GENERATE SUMMARY on the GSTR-1 dashboard. The invoice counts and tax amounts will populate in the tiles online. You can still modify or delete invoices online before you click submit.

FormatUsePortal upload accepted?
Excel workbookData entry and reviewNo
JSON filePortal transmissionYes
“Taxpayers can prepare details of outward supplies of goods or services in FORM GSTR-1 using Microsoft Excel based utility (GSTR_Excel_Utility) ... The Excel workbook contains worksheets for each table of Form GSTR-1” GSTN Manual: Returns Offline Tool

Check your own GSTR-2B

While you use the offline tool to file GSTR-1, you still need to reconcile the purchases flowing into your GSTR-2B. Match your purchase register against GSTR-2B securely in your browser.

Reconcile GSTR-2B

Last checked: 10 October 2026. Sources: GSTN Manual on Returns Offline Tool, GSTR-1 filing rules (tutorial.gst.gov.in), CBIC notification on GSTR-1 due dates.