While PAN is identifier at the entity level, GSTIN would be used ...
Circulars Customs
August 3, 2017
While PAN is identifier at the entity level, GSTIN would be used as identifier at the transaction level for every import and export. Further, in scenarios where GSTIN is not applicable, UIN or PAN would be accepted as IEC. - It is advised that all importers need to quote GSTIN in their Bills of Entry in addition to IEC. In due course of time IEC would be replaced by PAN/GSTIN.
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