Provisional assessment: pay duty provisionally pending final valuation, with bond, finalisation, and differential adjustment. Provisional assessment allows an assessee to pay duty provisionally when value or rate cannot be determined, requiring the assessee's application, execution of a bond, and an order specifying provisional rate or value. The Assistant/Deputy Commissioner must finalise assessment within the prescribed interval, with differential duty and interest payable if final duty exceeds provisional payment and refunds with interest if final duty is lower. Show cause or demand actions are generally deferred until finalisation except where misdeclaration or suppression is proved; provisional assessment is appealable and provisional for all consequential purposes.