Answers · Deductions, assets & depreciation
Ordinary and Necessary Business Expenses Explained
Business expenses are generally deductible when ordinary and necessary in carrying on a trade or business unless another rule capitalizes, limits or disallows them.
This question is answered in full on the main page for it.
How it works
The rule, and what it turns on.
IRC §162 is the starting point, not the end. Personal expenses, capital expenditures, substantiation requirements and special limits must also be tested.
Example
Commercial liability insurance for a repair shop is generally business expense; owner groceries are personal even if paid from business checking.
Common mistakes
What we see go wrong, and what we do instead.
- Treating every business-paid cost as deductible.
- No substantiation.
A better approach
- Create documentation requirements by expense type.
Authority
Where this comes from, so you can check it.
IRC §162(a) (ordinary and necessary trade or business expenses); IRC §262 (personal expenses generally nondeductible).
Relevant case law
Welch v. Helvering, 290 U.S. 111 (1933) - foundational interpretation of “ordinary and necessary.”
Educational information, not individualized tax advice. Treatment depends on your facts, entity classification and tax year, and IRS instructions change. Confirm your own position with us before relying on it. Mint Associates does not provide legal services.
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