For federal tax purposes, the determination of "business" or "hobby" is a matter of deduction. If your new venture is considered a business, you can deduct losses against other income.
However, when the activity is classified as a hobby, the "hobby loss" rules limit the amount you can write off. Expenses you incur might be deductible only if you itemize - or they might even be nondeductible.
The distinction affects the amount of tax you owe. So how can you prove you're trying to run a money-making business despite several years of losses?
One test you're probably familiar with is the general rule of earning a profit in three of the past five years. If your business has more income than deductions in three of five consecutive taxable years, the IRS generally accepts that you have a profit motive. (The time frame is two years in seven for certain horse-related activities.)
Unable to meet that test? Additional factors play a role as well. For instance, the Tax Court agreed that a volleyball consulting service with multiple loss years qualified as a business, in part because of a businesslike manner of operation. Among other items, the Court mentioned the maintenance of a separate bank account and accurate records as support for a profit motive.
Positive indicators of your profit-making intentions also include your expertise in the activity, the time and effort you put into your new business, and your success in other ventures.