GSTR-1 › Upload and file

Upload GSTR-1 on the GST portal: JSON or offline tool

The GST portal takes a JSON file, not Excel. The maker can save that JSON for you, or you can make it yourself in the free Returns Offline Tool from our Excel or CSV. Here are both paths, from your bills to a filed return.

Quick route: upload our JSON

1. In the GSTR-1 maker, pick the business, the period and your turnover band, and read the warnings.
2. Press Download JSON for the GST portal. Before saving, it checks your GSTIN and every buyer's GSTIN (check digit), the place of supply, the GST rates, bill and note numbers (16 characters at most: letters, digits, / and -) and HSN codes (4, 6 or 8 digits; 6 or more above ₹5 crore turnover). Anything wrong is listed in plain words: correct the bill on its own site, press Read saved bills again and download again.
3. The file is named like GSTR1_03ABCDE1234F1Z5_102026.json: your GSTIN and the period (month and year; a quarter uses its last month).
4. Upload it as shown under "On the GST portal" below, then check every table under Prepare Online before you file.

Once: get the offline tool

1. On www.gst.gov.in go to Downloads › Offline Tools › Returns Offline Tool and download it (version 3.2.4 when this page was written, 4 November 2026).
2. Unzip it and install GST Offline Tool. It runs on Windows only. The zip also holds the official Excel template and sample CSV files.

Offline tool route: make the JSON yourself

1. In the GSTR-1 maker, pick the business and period and press Excel workbook (all tables). (Or All CSV files for one file per table.)
2. Open the offline tool, choose New, select GSTR-1, type your GSTIN, financial year and tax period, and press Proceed.
3. Press Import Files. For the workbook use Import Excel; for a CSV pick the section (for example B2B) and use Import CSV.
4. Press View Summary and compare the totals with the maker's tiles. The tool works out the tax from the rate and taxable value; you can edit a tax amount if your bill shows a different one.
5. Add what the files cannot carry: port code and shipping bill for exports (when not typed on the invoice), and the documents issued and nil-rated tables if the tool did not import them (its help sheet says these two may need typing in).
6. Press Generate File. The tool saves a JSON file on your computer.

On the GST portal: upload and file

1. Log in, go to Services › Returns › Returns Dashboard, choose the year and period.
2. In the GSTR-1 tile choose Prepare Offline, then Upload, and pick the JSON file. Wait until the status says it was processed. If it shows errors, download the error file, open it in the offline tool, correct and upload again.
3. Go back, choose Prepare Online and check each table. E-invoices you registered on the IRP already appear here by themselves.
4. Press Generate GSTR-1 Summary, check it, then File Statement with DSC or EVC (OTP).

Things that trip people up

• E-invoices uploaded twice. If you use e-invoicing, those bills are already in GSTR-1 from the IRP. Uploading the same invoice number again replaces the entry; check the auto-filled entries instead of adding them again.
• Dates. The tool wants DD-MMM-YYYY (05-Nov-2026). The maker writes dates this way; if you edit in Excel, keep the cells as text.
• States. Place of supply must be written "03-Punjab", exactly as in the tool's list.
• Old template. If a future version of the offline tool asks for a newer template, copy the rows from our workbook into the new template's sheets with the same names.
• Bills from other software. The maker only knows bills saved in Nivesh Sahayak. Add other bills in the offline tool before you generate the JSON.