Kerala GST rules require bank account disclosure, exclude flood cess from taxable value, add QR codes, and enable duty free refunds. Registered persons (except specified classes) must furnish bank account details on the common portal within forty five days of registration or by the earlier return due date; failure is an actionable contravention. The value of supplies subject to Kerala Flood Cess is determined under section 15 but excludes the cess. Government may require QR codes on tax invoices and bills of supply. New procedural forms and provisions permit electronic cash ledger transfers (FORM GST PMT 09), replace 'payment advice' with 'payment order,' and establish refund procedures for airport retail outlets via FORM GST RFD 10B.