1. Through the macro analysis and calculation of massive data of tax collection and management, summarize the regular characteristics of taxpayers' tax economic relations, set corresponding early warning standards, establish an early warning system, and screen key tax assessment objects through the early warning system;

2. Conduct a preliminary desk review and comparison of the tax information declared by the tax assessment object, and determine the direction and focus of further assessment and analysis;

3. Through the comparative analysis of horizontal data, the analysis of vertical data rules and the analysis of the relevant rationality of the logical relationship of data indicators, we can infer and confirm the authenticity and doubts of the taxpayer's declared data, estimate the taxpayer's potential production and operation income, and infer the taxpayer's actual tax paying ability;

4. Interview the taxpayer on the assessed problems, doubts and inferred tax paying ability. If the taxpayer can accept the evaluation results, he will check the tax according to the tax source evaluation; If the taxpayer cannot accept the evaluation results, the evaluation data shall be handed over to the inspection department for filing and inspection.

Tax assessment refers to the management behavior that tax authorities use the method of comparative analysis of data information to analyze the authenticity and accuracy of tax returns of taxpayers and withholding agents, and verify them through tax letters, tax interviews, on-the-spot investigations, etc., so as to make qualitative and quantitative judgments and take further collection and management measures.

Legal basis: Article 8 of the Legislative Law of People's Republic of China (PRC).

The basic tax system can only be formulated by the National People's Congress and its Standing Committee.