Chapter 5: Business Deductions
5-1 OVERVIEW OF BUSINESS DEDUCTIONS The Code does explicitly allow the deduction of expenses incurred in a trade or business, but only if those expenses are ordinary, necessary, and reasonable in amount. 5-1a Ordinary and Necessary Requirement Section 162(a) permits a deduction for all ordinary and necessary expenses paid or incurred in carrying on a trade or business. To understand the scope of this provision, it is critical to understand the meanings of the terms ordinary and necessary. Since these terms are not defined in the Code or Regulations, the courts have dealt with these terms on numerous occasions. An expense has been held to be ordinary if it is normal, usual, or customary in the type of business conducted by the taxpayer. Note that an expense need not be recurring to be considered ordinary. For example, a business may incur an expense related to a rare and unusual event. However, if other businesses in a similar situation are likely to incur a similar expense, the...