TDS on GST supplies: prescribed CGST/SGST and IGST rates apply; valuation excludes GST and exempt supplies, threshold governs deduction. TDS on GST supplies is deducted by reference to the nature and location of supply: 1% CGST and 1% SGST/UTGST where supplier and place of supply are in the same State/UT, and 2% IGST where they are in different States. The valuation for deduction excludes GST taxes and cess and excludes exempt supplies even if billed together. Deduction obligation is assessed contract-wise: no deduction if the taxable value under a particular contract does not exceed the applicable threshold; composition registration does not automatically exempt a supplier from deduction when the contract-wise taxable value exceeds the threshold.