Are the Social Security Bureau and the Tax Bureau a unit?

No, the social security bureau and the tax bureau are two different units, each with its own responsibilities. The Social Security Bureau is an administrative agency under the Municipal Human Resources and Social Security Bureau, which is responsible for the collection and management of the city's social insurance funds; The Tax Bureau is the directly affiliated institution in charge of tax work in the State Council, responsible for drafting tax laws and regulations, organizing and implementing tax collection and management, and handling import and export commodity tax through system reform.