The annual social security base refers to the highest and lowest social security contributions of employees stipulated by the state. Under normal circumstances, the social security base will be adjusted according to economic factors such as urban development level, residents' income level and inflation. The adjustment of the social security base is to ensure that the social security contributions of employees are within a reasonable range and protect the rights and interests of employees.

According to national regulations, the adjustment of social security base should be adjusted according to the level of social and economic development. Since 20 18, China has adjusted the national social security base by taking into account the income level of urban and rural residents, price changes and other factors. In addition, the social security base of the previous year was adjusted according to the national per capita disposable income level and the average personal consumption level to ensure the rationality and effectiveness of the base.

The social security contributions of employees are affected by the social security base to some extent. High social security base will lead to excessive burden on some employees and affect their living standards. The low social security base will affect the income of social security funds and the effectiveness of social security benefits. Therefore, the adjustment of social security base should be carried out in strict accordance with state regulations to ensure the safety of social security funds and the rights and interests of employees are not damaged.