Permanent Account Number requirement triggers higher withholding where PAN not furnished; limited relaxations for certain non residents apply. Requirement to furnish Permanent Account Number mandates PAN for all payees subject to withholding; absent or invalid PAN triggers higher rate deduction as the greater of the statutory rate, the rate in force or a prescribed fallback, with special fallback for certain transactions. Declarations and certificates reducing withholding are invalid without PAN. Specified procedural relaxations permit certain non resident natural persons without PAN to avoid higher deduction if they supply prescribed identity, residence and tax identification documents.