What is Treasury Regulations?

Legal Definition
Treasury Regulations are the tax regulations issued by the United States Internal Revenue Service (IRS), a bureau of the United States Department of the Treasury. These regulations are the Treasury Department’s official interpretations of the Internal Revenue Code and are one source of U.S. federal income tax law.
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Legal Definition
Regulations that interpret the Internal Revenue Code are compiled under Title 26 of the Code of Federal Regulations. These regulations are generally issued by the United States Department of the Treasury.