What is a sole proprietor? Nic Ruiz August 19, 2018 19:05 A sole proprietor is someone who owns an unincorporated business by himself or herself. See definition here: https://www.irs.gov/businesses/small-businesses-self-employed/sole-proprietorships. Related articles I'm stuck in the income-expense loop. Can you help? The different ways to be self-employed How do I find the value of my motor vehicle if it's not listed in KBB? I don't have enough income to pay for regular living expenses. Is now the right time to file bankruptcy? Can I file for bankruptcy after moving to a new state? Comments 0 comments Article is closed for comments.