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Georgetown Law Library

Tax Research - Federal

This guide on federal tax research explains where and how to find tax materials.

Internal Revenue Bulletin Guidance

Revenue Ruling (Rev. Rul.)

A Revenue Ruling is an official interpretation by the IRS of the Code, related statutes, tax treaties, and regulations. It explains the IRS's position on how the law is applied to a specific set of facts. 

Any taxpayer whose circumstances are substantially the same as those described in the Ruling can rely on it.

Revenue Procedure (Rev. Proc.)

A Revenue Procedure is an official statement of a procedure that affects the rights or duties of taxpayers under the Code, related statutes, regulations, and treaties that should be a matter of public knowledge. Generally, it provides instructions for return filing or other procedures. Sometimes it may have a substantive effect (e.g., interest rate tables).

Notices

Notices provide interim guidance before finalized revenue rulings and regulations are available.

Announcements (Ann.) 

Announcements are public pronouncements that have only immediate or short-term value (e.g., extension of filing deadlines for areas hit by natural disasters).

Finding IRB Guidance

The Internal Revenue Bulletin (I.R.B.) is published weekly and compiled semi-annually into the Cumulative Bulletin (C.B.). Note that the C.B. ceased publication in 2008.

Specialized Tax Databases

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