Electronic invoices can be deducted, but guarantee documents can't. According to Article 11 of People's Republic of China (PRC) Contract Law, the invoice is the legal form of the contract, so the form of guarantee has the same legal effect as electronic invoice and paper invoice. After printing, the electronic guarantee form becomes a paper guarantee form. 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 electronic invoice is attached with the signature mechanism of the electronic tax bureau, so the guarantee is not an invoice.