Tax Research - Federal Guide

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

Other IRS Guidance

Private Letter Rulings (Ltr. Rul., P.L.R., Priv. Ltr. Rul.)

A Private Letter Ruling is a written statement issued to a taxpayer by the national office of the IRS that interprets and applies the tax laws to the taxpayer's specific set of proposed facts. Letter Rulings are similar to Revenue Rulings, but they are relied upon as precedent only by the taxpayer to whom the ruling is issued. The name and other identifying information concerning the taxpayer requesting the P.L.R. is redacted. Private Letter Rulings are not officially published in a reporter.

Technical Advice Memoranda (TAM)

A Technical Advice Memorandum is written guidance provided by the national office of the IRS upon the request of an IRS District Director or an IRS Area Director of Appeals. A TAM responds to a technical or procedural question that develops during the examination of a taxpayer's return, the consideration of a taxpayer's claim for refund, or any other matter that involves the jurisdiction of a District Director or Area Director of Appeals. A TAM only addresses issues that are covered by previously published authority, such as the IRS, a treasury regulation, tax treaty, revenue ruling, or other precedent. These statements are similar to Letter Rulings, however they are in response to completed tax payer transactions and hold no precedential authority for tax payers other than the intended taxpayer. Technical Advice Memoranda are not officially published in a reporter.

Chief Counsel Memoranda

The Office of Chief Counsel drafts numerous types of internal advice issued to attorneys and revenue agents within the IRS. These documents have no precedential value and cannot be relied on by taxpayers. Nonetheless, they may be useful for background or insight into a position the IRS might take on an undecided or novel issue for which no other agency guidance is available.

The Office of Chief Counsel has issued various types of internal guidance with different names, including:

  • Field Service Advice Memoranda
  • Litigation Guideline Memoranda
  • General Counsel's Memoranda
  • Technical Memoranda

Chief Counsel advice is not officially published.


IRS Forms and Publications

Tax forms, instructions, and other instructional publications are directed towards both professionals and non-professionals.

IRS News Releases

Specialized Tax Databases

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