GST registration: timely application and verification required, with unique identity numbers for certain international entities. Persons liable to register must apply within the prescribed period, with casual and non-resident taxpayers subject to earlier application and territorial waters supplies registered in the nearest baseline State. Single registration is standard, separate registrations may be granted for business verticals, and voluntary registration applies. PAN is required for registration, with TDAN accepted for deductors and alternative documents for non-resident taxable persons. Proper officers may register non-compliant persons. Notified international entities and consular missions may receive a Unique Identity Number. Registration or UIN issuance is subject to prescribed verification, a prescribed-form certificate is issued, and registration is deemed granted if no deficiency is notified within the verification period.