Skip to main content

Federal Tax Research

This research guide is for those who have a basic idea of tax law and its sources

If you are looking for a particular tax source:

These are arranged alphabetically by abbreviations. The abbreviations are followed by the name, law library call number, and free online source.  Most tax sources can be found on Bloomberg LawCCH IntelliconnectLexisNexisRIA/Checkpoint, and  WestlawNext. For a clear quick refresher on the sources see the Internal Revenue Manual section entitled “Researching Tax Law” 4.10.7.2.

  • AOD, Action on Decision, published in the Internal Revenue Bulletin, KF 6282. A2I496, IRS’s AOD
  • BTA, Reports of the United States Board of Tax Appeals*, KF 6280 .A2 T36
  • CB, Cumulative Bulletin, KF 6282 .A21571
    • The Cumulative Bulletin contains the full text of Revenue Procedures, Revenue Rulings, Treasury Decisions, as well as other information. The spine of each volume indicates which Rev. Proc., Rev.Rul., and T.D. in the volume.
  • CCA, Chief Counsel Advice, IRS’s Written Determinations
  • CFR, Code of Federal Regulations, Reserve Range 63, GPO’s CFR
  • Cl. Ct., United States Claims Court Reporter, 3rd Floor Range 50 (Court abolished in 1982).
  • Fed. Cl., Court of Federal Claims, 3rd Floor Range 50, Court’s site.
  • GCM, General Counsel Memorandums*published in the Cumulative Bulletin, KF 6282 .A21571
  • IRB, Internal Revenue Bulletin, KF 6282. A2I496, IRS’s IRB
    • The Internal Revenue Bulletin contains Announcements, Notices, and Action on Decisions, in additional to Revenue Rulings and Revenue Procedures.
  • IRC, Internal Revenue Code is 26 U.S.C., See, U.S.C.: United States Code 3rd Floor Range 46, GPO’s USC
  • LTR, Private Letter Ruling* (CCH), KF 6282 .A2 I5 – See, PLR, Private Letter Rulings,* IRS’s Written Determinations
  • PLR, Private Letter Ruling,* IRS’s Written Determinations
  • Rev. Proc., Revenue Procedure, published in the Internal Revenue and Cumulative Bulletins
  • Rev. Rul., Revenue Ruling, published in the Internal Revenue and Cumulative Bulletins
  • TAM, Technical Advice Memorandums, IRS’s Written Determinations
  • T.C., Reports of the United States Tax Court, KF 6280 .A2 . T37, Court’s site.
  • T.D., Treasury Decisions (i.e. Regulations), published in the Cumulative Bulletin, KF 6282 .A21571
  • TC Memo, TC Memorandum Decisions* (RIA), KF 6280 .A2 T39
  • TCM, Tax Court Memorandum Decisions* (CCH), KF 6280 .A2 T393
  • U.S.C., United States Code, 3rd Floor Range 46, GPO’s USC

*Note, many tax sources are not “published” by the government entity that creates them.  When this is the case, start with either CCH IntelliconnectBloomberg Law, or RIA/Checkpoint as these commercial publishers have long specialized in gathering tax law information.