EXECUTIVE SUMMARY

Primary sources of U.S. tax law that carry a high weight of authority are as follows:

  • Internal Revenue Code
  • Final and temporary treasury regulations
  • Judicial decisions on tax matters
  • Revenue Rulings
  • Revenue Procedures
  • Other published IRS positions: IRS Notices and Announcements.

There are certain other primary sources providing guidance which, generally, should not be cited as legal authority. Such sources include proposed treasury regulations, unless they are specifically earmarked as “reliance regulations”, IRS Private Letter Rulings, Determinations letters, Technical Advice Memorandum, IRS Publications, Federal tax forms and form instructions, IRS FAQ.

Taxpayers can use IRS informal guidance, including Federal forms, instructions, publications, FAQs, IRS.gov webpages. Informal guidance has not been published in the Internal Revenue Bulletin (IRB) and should not be relied on as a legal precedent. However, taxpayers’ reasonable reliance on informal guidance is relevant. Such reliance generally results in no tax penalty associated with underpayment of taxes.

IRS uses the Internal Revenue Bulletin (IRB) as the authoritative instrument for communicating IRS official rulings and procedures.

Secondary sources are publications written by legal analysts, scholars, and other tax professionals. These sources generally include unofficial guidance such as treatises, journals and newsletters.

Some tax professionals may use relevant and reliable secondary sources as part of internal considerations to substantiate a taxpayer position. However, secondary sources of tax law are not mentioned in legal proceedings or preparing official communications with IRS.