Title 26 of the United States Code

The Internal Revenue Code (IRC), formally the Internal Revenue Code of 1986, is the domestic portion of federal statutory tax law in the United States, published in various volumes of the United States Statutes at Large, and separately as Title 26 of the United States Code (USC). It is organized topically, into subtitles and sections, covering income tax (see Income tax in the United States), payroll taxes, estate taxes, gift taxes, and excise taxes; as well as procedure and administration. Its implementing agency is the Internal Revenue Service.

Prior to 1874, U.S. statutes (whether in tax law or other subjects) were not codified. That is, the acts of Congress were not separately organized and published in separate volumes based on the subject matter (such as taxation, bankruptcy, etc.). Codifications of statutes, including tax statutes, undertaken in 1873 resulted in the Revised Statutes of the United States, approved June 22, 1874, effective for the laws in force as of December 1, 1873. Title 35 of the Revised Statutes was the Internal revenue title. Another codification was undertaken in 1878.

In 1919, a committee of the U.S. House of Representatives began a project to recodify U.S. statutes, which eventually resulted in a new United States Code in 1926 (including tax statutes).

The tax statutes were re-codified by an Act of Congress on February 10, 1939 as the "Internal Revenue Code" (later known as the "Internal Revenue Code of 1939"). The 1939 Code was published as volume 53, Part I, of the United States Statutes at Large and as title 26 of the United States Code. Subsequent permanent tax laws enacted by the United States Congress updated and amended the 1939 Code.

On August 16, 1954, in connection with a general overhaul of the Internal Revenue Service, the IRC was greatly reorganized by the 83rd United States Congress and expanded (by Chapter 736, Pub.L. 83–591). Ward M. Hussey was the principal drafter of the Internal Revenue Code of 1954. The code was published in volume 68A of the United States Statutes at Large. To prevent confusion with the 1939 Code, the new version was thereafter referred to as the "Internal Revenue Code of 1954" and the prior version as the "Internal Revenue Code of 1939". The lettering and numbering of subtitles, sections, etc., was completely changed. For example, section 22 of the 1939 Code (defining gross income) was roughly analogous to section 61 of the 1954 Code. The 1954 Code replaced the 1939 Code as title 26 of the United States Code.

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