Formal:
* Company Driver: This is the most straightforward and general term.
* Chauffeur: This term is more formal and usually refers to someone who drives a luxury car for a specific individual or company.
* Fleet Driver: This term refers to someone who drives a vehicle that is part of a company's fleet.
Informal:
* Company Car Driver: This is a less formal way to describe someone who drives a car owned by the company.
* Driver: This is a general term that can be used in many contexts.
The best term to use will depend on the specific situation and the level of formality required.