Tax Deduction at Source under GST requires DDOs to register, deduct prescribed TDS on large contracts and remit timely. DDOs must register as tax deductors on the GST portal using TAN, obtain GSTIN, and deduct prescribed TDS on taxable government procurements above the threshold (excluding supplies from outside the State) calculated on the taxable contract value excluding GST and cess. Deducted amounts must be remitted via the GST challan process within the statutory time after the month of deduction, using the designated bank account and quoting CPIN/CIN; an electronic TDS certificate must be issued within five days of remittance and a monthly TDS return filed by the due date. Interest, fees and penalties attach for delay or default and DDOs are personally liable.