Inter State supply reporting: ensure place of supply entries in GSTR 3B and GSTR 1 for correct GST settlement. Suppliers must report inter State supplies to unregistered persons, composition taxpayers and UIN holders place of supply wise in GSTR 3B Table 3.2 and the corresponding GSTR 1 tables; maintain correct customer state details so portal auto population aligns with invoices. Table 4(A) of GSTR 3B is auto populated from GSTR 2B; permanent reversals and ineligible ITC (e.g., under rule 42/43 and section 17(5)) must be declared in Table 4(B)(1), temporary reversals in Table 4(B)(2), and Net ITC = 4A - [4B(1)+4B(2)] which is credited to the Electronic Credit Ledger; time barred ITC should be reported in 4(D)(2).