Outsourcing companies only need catering invoices and taxi invoices to be able to deduct VAT output tax. VAT is a kind of turnover tax that is levied on the basis of the value-added amount of goods (including taxable services) generated in the process of turnover. In terms of taxing principle, VAT is a turnover tax levied on the new value added or the added value of commodities in multiple stages of commodity production, distribution and labor services. It is an out-of-the-price tax, that is, it is borne by the consumers, and it is taxed only if there is value-added, but not if there is no value-added.