The IRS's Nine Factors That Distinguish a For-Profit Business From a Hobby for Tax Deduction Purposes

For the nearly 40% of Americans operating a side hustle, the difference between a legitimate business and a personal pastime comes down to a single section of the tax code: Internal Revenue Code Section 183. If the Internal Revenue Service (IRS) determines an activity is a business, the operator can deduct expenses like equipment, travel, and supplies to lower their taxable income. If the agency reclassifies the activity as a hobby, the operator loses every dollar of those deductions, yet remains fully taxed on the gross revenue generated.[1][2]

The stakes for this classification are absolute. Prior to the 2017 Tax Cuts and Jobs Act, taxpayers could deduct hobby expenses up to the amount of hobby income as a miscellaneous itemized deduction. That provision was suspended, meaning hobbyists now face a scenario where they pay tax on their gross receipts while absorbing the costs entirely out of pocket.[3][5]

To navigate this divide, the IRS relies on a nine-factor test outlined in Treasury Regulation Section 1.183-2. The agency explicitly states that no single factor is determinative, and auditors are instructed to weigh the totality of the circumstances. As Fusion Taxes notes, 'The IRS considers a hobby to be any activity that a person pursues without the intention of making a profit.'[1][5]

The first and most heavily scrutinized factor is whether the taxpayer carries on the activity in a businesslike manner. This requires maintaining complete and accurate books, keeping separate bank accounts for the enterprise, and operating with a formal business plan. Commingling personal and business funds is consistently cited as a primary trigger for hobby reclassification.[2]

The second and third factors examine the taxpayer's expertise and the time and effort expended. The IRS looks at whether the operator has acquired specialized knowledge, consulted with industry experts, and devoted sufficient personal time to indicate a genuine intention to turn a profit, rather than simply enjoying a recreational pastime.[1][4]

Factors four and five evaluate the expectation that assets used in the activity may appreciate in value, and the taxpayer's past success in similar or dissimilar activities. An operator who has previously turned unprofitable ventures into successful businesses is granted more leeway during the startup phase of a new enterprise.[1]

The sixth and seventh factors focus on the history of income and losses. While startup losses are expected, the IRS examines whether losses continue beyond the customary development period for that specific industry. If an activity generates occasional profits, the agency weighs the magnitude of those profits against the magnitude of the losses.[1][2]

The final two factors assess the taxpayer's financial status and the elements of personal pleasure involved. If the operator relies on the activity's income for their livelihood, it strongly suggests a profit motive. Conversely, if the activity generates substantial losses that conveniently offset a high salary from a primary job, and the activity involves significant recreational appeal—like horse breeding or photography—the IRS is highly likely to challenge the deductions.[3][4]

To provide a safe harbor, the IRS offers a profit presumption rule. If an activity generates a net profit in at least three of the last five consecutive tax years, the agency generally presumes it is a for-profit business. For activities involving breeding, training, showing, or racing horses, the threshold is two out of seven years. Meeting this standard shifts the burden of proof back to the IRS during an audit.[2]

Protecting a side hustle from hobby reclassification requires proactive documentation. Operators must build a paper trail of their profit intent long before tax season arrives, treating their recordkeeping with the same rigor as their actual product or service. The deciding party is the IRS examiner, and organized financial records remain the strongest defense against losing vital tax deductions.[4][5]