# Filing GSTR-1: Import Sales Register

Octa uses your **sales register** (all your outward supplies/invoices) to automatically prepare accurate **GSTR-1**,
handle reconciliations, calculate correct tax liability, and generate summaries — saving you hours of manual work every
month!

You can bring in sales data from **any source** (Amazon, Flipkart, your ERP like Tally/Busy, website sales, offline
invoices, etc.) and in multiple formats — Octa combines everything perfectly into one clean GSTR-1 return.

**Ready to import?**

Follow our simple step-by-step guide to bring your sales data into Octa quickly and error-free:

**[Importing Sales Register in Octa →](/octa/docs/app/importing-sales-register/overview)**

Inside the guide, you'll find detailed instructions for each format: Amazon MTR, Flipkart GST Report, GSTR-1 format from
ERP, and the flexible Octa Format — plus tips for handling multiple GSTINs, fixing errors, and more.