Tax Law Research Guide: Free Online Resources

The Internal Revenue Service is the nation's tax collection agency and administers the Internal Revenue Code enacted by Congress.

The Treasury Department is the executive agency responsible for promoting economic prosperity and ensuring the financial security of the United States.

The Code of Federal Regulations (CFR) annual edition on FDSys is the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. It is divided into 50 titles that represent broad areas subject to Federal regulation. The 50 subject matter titles contain one or more individual volumes, which are updated once each calendar year, on a staggered basis.

The Office of the Federal Register (OFR) of the National Archives and Records Administration (NARA), and the U.S. Government Publishing Office (GPO) jointly administer the FederalRegister.gov website. This site was developed to make it easier for citizens and communities to understand the regulatory process and to participate in Government decision-making.

The United States Government Manual is the official handbook of the Federal Government. This special edition of the Federal Register is currently updated to provide comprehensive and authoritative descriptions of the programs and activities of the legislative, judicial, and executive branches. The Government Manual also includes information about quasi-official agencies, international organizations with U.S. membership, and Federal boards, commissions, and committees.

LII is a not-for-profit group that provides free online resources to the public. Among its many offerings, the LII website includes links to the U.S. Code, CFR, select Court decisions, the U.S. Constitution, and many other primary and secondary sources of law.