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Business: Accounting

Tax Research

Primary Sources (Original Pronouncements)

Statutory Sources

  • U.S. Constitution - source of federal tax laws
  • Tax Treaties - agreements negotiated between countries concerning the treatment of entities subject to tax in both countries
  • Internal Revenue Code - collection of laws that have been passed by Congress and incorporated in Title 26 of the United States Code.

Administrative Sources

  • Treasury Regulations - constitute the IRS's and, thereby, the Treasury's official interpretation of the Internal Revenue Code
  • Revenue Rulings - official pronouncements of the National Office of the IRS; deals with the application of the Code and Regulations to a specific factual situation
  • Revenue Procedures - internal practice and procedures of the IRS in the administration of tax laws; constitute the IRS's way of releasing information
  • Other Written Determinations
  • Miscellaneous IRS Publications

Judicial Sources

  • Supreme Court
  • Courts of Appeals
  • District Courts
  • U.S. Court of Federal Claims
  • Tax Court
  • Tax Court, Small Cases Division



What's the difference?

The United States Code (USC) is the official record of the laws passed by Congress.

The Code of Federal Regulations (CFR) is the official record of the interpretations of the USC by the relevant departments.