I'm wondering what is the term for the person, that is doing business on his/her own and has tax liability. It's different in each country, I'd like to know how they are called in USA and UK.
Sole Proprietor: the person who owns and controls a sole proprietorship.
I am the sole proprietor of this business.
Independent Contractor: A person working independently, under a contract; a self-employed person.
I am an independent contractor.
Self-Employed (or Freelancer): working for yourself.
I am self-employed.
I am a freelancer.
In Australia, they can be self-employed, freelancers, contractors, sole practitioners (for professional services), sole traders (for other services), and probably a lot more besides... I don't know if I have heard of sole proprietors here.
Sole proprietorship or simply proprietorship. The owner is called the proprietor.
In the UK, a one person business is often referred to as a one-man band.
"My consulting business is actually just me. I'm a bit of a one-man band at the moment"
It comes from the practice of a street entertainer playing multiple instruments at once.
The question is vague.
In the U.S, "sole proprietor" is a legal term that signifies the one human being who is responsible for the debts of a business and legally entitled to the profits of the business. A sole proprietorship is distinguished legally from partnerships and corporations, in which the debts of a business are not the responsibility of a single, "natural person," another term of legal art. In usual practice, a sole proprietor is also the daily manager of the business, but this need not be true. Nor is it necessarily true that a sole proprietorship has only one person working at the business. It refers to a technical legal relationship. (See Wikipedia for "sole proprietor.")
In the U.S., one term commonly used for people who work for themselves is "self-employed," regardless of the legal form of ownership, which would not normally be known or of significance to most people. That term, however, does not imply that the person works alone. A person who owns and runs a small shop with several employees would still be called "self-employed." A person who works alone may be called a "sole practitioner" or a "lone practitioner" although that term encompasses people who do not work alone so long as those with whom they work are in an auxiliary capacity. Thus a doctor who is not in a group practice would be referred to as a sole practitioner even though the doctor may employ a nurse or secretary or receptionist, none of whom practice medicine.
EDIT: I see the the OP was particularly interested in the incidence of taxation. The entity that has primary liability for taxes depends on the exact legal form under which the business operates. There is, however, a doctrine in U.S law called "piercing the corporate veil" that may impose secondary liability for corporate debts on other parties. Moreover, U.S. tax law is arcane and Byzantine and so is the domain of highly specialized accountants and lawyers. Any questions about primary and secondary liability for taxes should be asked of those specialists. I won't even venture a guess.
The term self-employed without employees seems to be used by multiple organisations:
I'd rather think that proprietor means owner what, in turn, means that such person is not necessarily working in his/her business alone.. One person business would be the best..
Sole proprietorship is a person that own and run a business on its own depending on no body. He bears the risk on its own.