GSTR-1 JSON upload errors on the GST portal and how to fix them

A GSTR-1 JSON upload goes wrong in one of two ways. Either the GST portal refuses the file itself, or it takes the file and marks it Processed with Error because some rows failed its checks. The error report names those rows. Correct them, create the JSON again and upload it once more.

How does the offline upload work?

You can type GSTR-1 on the portal or upload it as a JSON file, a plain data file that holds your invoices and summaries. The file comes from the government's Returns Offline Tool or from other software that follows the portal's format. To upload, log in and open Services, Returns, Returns Dashboard. Pick the year and period, click Prepare Offline on the GSTR-1 tile and choose the file. The whole filing is covered in file GSTR-1 on the portal step by step.

The portal gives the upload a reference ID and shows it as In-Progress. Some minutes later the status becomes Processed or Processed with Error. Why so strict? Your B2B invoices flow to your buyers, who claim input tax credit (the GST they paid on purchases) from them. It is cheaper to stop a wrong row at upload than to amend it later.

How do you download and read the error report?

1. On the Upload page, find the row marked Processed with Error and click Generate error report.
2. Wait. The portal's help file says the report is ready in around 15 minutes. A Download error report link then appears.
3. Save the file. It downloads as a zip.
4. Open the Returns Offline Tool, choose the option to open an error file downloaded from the GST portal, and select the zip.
5. The tool shows only the sections that have errors, with the reason against each invoice number.
6. Edit or delete each failed row and save. Then view the summary, generate a fresh JSON and upload it.

If your JSON came from other software, use the report as a list of what to fix in your sales data, then generate the file again there.

What usually causes the error?

Three more causes are often blamed: an HSN code outside the portal's list, an invalid place of supply code, and tax that does not equal rate times value. On the portal screen, the HSN code in Table 12 can only be picked from a list, so a code outside it is likely to fail in a file too. We did not find an official page that describes the other two, so let your error report confirm them. More on HSN in Table 12 of GSTR-1.

A worked example

Kavya sells kitchenware from Jaipur. Her March 2026 file has 40 B2B invoices. The status shows Processed with Error. The report lists two rows.

Invoice JP/0412 for Rs 23,600 (Rs 20,000 plus GST of Rs 3,600 at 18%) was already in her February return. It is a duplicate, so she deletes it. Invoice JP/0431 for Rs 11,800 went to a buyer whose registration is no longer active. She asks the buyer for the current GSTIN and corrects the row. She generates a new JSON and uploads it. The status turns to Processed. The other 38 invoices needed no change.

What mistake do sellers usually make?

They upload the same file again without opening the report. The same rows fail again.

The second mistake is with split files. A row uploaded twice replaces the earlier copy, which helps. But summary sections such as the HSN summary are replaced in full by the later upload. So if you split a big return, keep the complete HSN summary in the last file. Then click Generate GSTR-1 Summary and check the totals against your sales report before you file.

Should you fix it yourself?

Yes, when the report has a handful of rows and the reason is plain. Take help when hundreds of rows fail for the same reason. That points to the way your data is prepared, such as a numbering pattern that repeats across marketplaces. See Table 13, documents issued for how invoice series work.

Frequently asked questions

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