Legal analysis: the validity period of invoices varies according to the types of invoices. 1. The special VAT invoice is valid for 180 days. 2. Ordinary invoice is valid for 6 months.

Legal basis: Notice of State Taxation Administration of The People's Republic of China City, People's Republic of China (PRC) on Issues Related to Adjusting the Deduction Period of VAT Deduction Vouchers 1. General taxpayers of value-added tax shall go to the tax authorities for certification within 10 days after obtaining special invoices for value-added tax, unified invoices for road and inland waterway cargo transportation and unified invoices for motor vehicle sales issued after 20/kloc-0+00, and within the reporting period of the next month after passing the certification.