GSTR 3B not auto populating

Also you have to take care , that Your GSTR1 and GSTR3B should Tally.

GSTR-3B auto-population works differently for each table, which is where most of the confusion comes from.

Table 3.1 (outward supplies): this does not auto-populate at all. You fill it manually from your own sales records or pull from GSTR-1.

Table 4 (ITC from purchases): this pulls from GSTR-2B, generated on the 14th of each month. Two things to check:
- IMS (Invoice Management System): log in and verify inward invoices from suppliers show as Accepted. Pending or rejected invoices block ITC from appearing.
- GSTR-2B availability: check Return Dashboard. If GSTR-2B for May 2026 is not yet generated, compute ITC manually from your purchase register.

For May 2026 GSTR-3B (due June 20), do not wait for the portal. Compute ITC from your purchase register, cross-check with GSTR-2B, and file before the deadline. Late fees at Rs 50 per day apply from June 21.

The types and timelines for each GST return, including GSTR-3B filing logic, are covered in this [GST returns guide for FY 2026-27](https://taxgarden.in/blog/types-of-gst-returns-india-2026).