Haishu District of Ningbo can open electronic invoices on mobile phones. Log in to Ningbo Electronic Taxation Bureau and click I want to inquire, invoice information and billing information on the main page. Electronic invoice is the product of the information age. Like ordinary invoices, they are distributed to merchants in the form of unified issuance by the tax bureau. The invoice number is distributed to merchants with national unified coding and unified anti-counterfeiting technology. The signature mechanism of the electronic tax bureau is attached to the electronic invoice.