Is hsn code mandatory for turnover less than 1.5 crore in gstr1

HSN codes are not required on B2C invoices for turnovers up to ₹1.5 crore.

You can optionally include it in GSTR-1 or leave it blank.

But for B2B transactions:
Some portals and updates may mandate at least 4-digit HSN even for smaller businesses, especially if dealing with B2B or exports.
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