Section 31 - Tax invoice.

Tax invoice requirement: timing, exceptions, and alternative documents under GST, including revised invoices and vouchers.

A registered person supplying taxable goods must issue a tax invoice at or before removal or delivery showing prescribed particulars; for taxable services a tax invoice must be issued within a prescribed period. Exceptions allow revised invoices after registration, exclusion for low-value supplies, issuance of a bill of supply for exempt or composition supplies, receipt vouchers and refund vouchers for advances, and recipient-issued invoices and payment vouchers where reverse charge applies. Continuous supply and service-linked payment rules prescribe invoice timing tied to statements, payments, contract due dates, receipt of payment or completion of events.