The Internal Revenue Service (IRS) is the revenue service for the United States federal government. It is a bureau of the Department of the Treasury, and is responsible for collecting taxes and administering the Internal Revenue Code, which is the principal tax law of the United States.
As of 2022, the IRS employs approximately 80,000 people. The majority of IRS employees work in one of the agency’s 10 regional offices or in one of its 600 field offices. The IRS also has a number of employees who work in Washington, D.C., including the Commissioner of Internal Revenue, who is the head of the agency.