TDS under GST: mandatory withholding by government deductors where contract value exceeds threshold, with filing and ledger deposit obligations. TDS under GST requires specified government deductors to withhold tax on payments to suppliers where the aggregate taxable value of a contract exceeds the threshold, excluding GST components. Deductors must register, obtain GSTINs, know vendor GSTINs, and deposit deducted tax via CPIN and by debiting the Electronic Cash Ledger when filing FORM GSTR 7. The rate and nature of deduction depend on supplier location and place of supply; suppliers receive system generated FORM GSTR 7A credits which they may accept or reject, and refunds for excess deductions follow statutory refund provisions.