CPA REG · Ethics, Professional Responsibilities and Federal Tax Procedures · Free Lesson

Substantiation and Disclosure

Free CPA REG (Taxation & Regulation) lesson in Ethics, Professional Responsibilities and Federal Tax Procedures. 14 min read, ~2,088 words.

A taxpayer claims $18,000 of business meals and produces credit card statements at audit but no logs of attendees, business discussed, or location. Under §274, the IRS disallows the entire deduction even though the money was spent. Substantiation is not "proof I paid." It is "the specific records the Code requires."

The §6662 accuracy-related penalty is 20% of the underpayment from negligence or substantial understatement. Two paths avoid it: strong authority, or disclosure of a weaker position on the right form. Substantiation rules decide whether your records support the deduction at all.

The Cohan rule comes from a 1930 case where George M. Cohan deducted business expenses without receipts. Courts may estimate deductible amounts when the taxpayer credibly establishes that some expense was incurred. The estimate falls heavily against the taxpayer, but you do not lose the entire deduction for poor records. Cohan applies to ordinary business expenses, charitable cash contributions under $250, and similar deductions where the existence of the expense is not in doubt.

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Common mistakes

Bottom line

Exam shortcut

When a question gives a confidence percentage, anchor on three numbers: 20% reasonable basis, 40% substantial authority, 50% more likely than not. Substantial authority avoids §6662 silently, no form. Reasonable basis ALWAYS needs Form 8275 (or 8275-R if contrary to a regulation). For §274 categories, "I have receipts" is never enough, need amount, time, place, business purpose, AND business relationship.

The full lesson (about 2,088 words, 14 min read) adds 2 worked examples, all 6 common mistakes, a self-check, free in the app.

Learning objectives

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