TDS under GST requires specified government and notified entities to deduct tax at source on taxable supplies with compulsory registration. TDS under GST mandates specified government departments, local authorities, governmental agencies and notified entities to deduct tax at source on all taxable goods or services. The notification lists authorities, boards, government-established societies, public sector undertakings and buyers of metal scrap as deductors, while excluding certain defence authorities and supplies between public sector undertakings or among specified deductor classes. Deductors must obtain compulsory GST registration as TDS deductors and a GSTIN via the online portal, irrespective of prior supplier registration.