A proprietorship is a business structure in which the owner and the business are combined for both liability and tax purposes. This means that a liability incurred by the business is also a liability of the owner, and vice versa. Further, the owner reports the results of the business in his or her personal tax return. A proprietorship is not registered with the state government, which means that there is no legal documentation of its existence.
A proprietorship is also known as a sole proprietorship.