Simon Woodcock, the former operator of Elite Taxis, based in Wellington Street, Barnsley, was prosecuted by council officers who launched an inquiry after receiving complaints from the public.
Woodcock, 40, of Arundel Gardens, Royston, was charged with five offences including using unlicensed vehicles and drivers and allowing vehicles to be driven without valid insurance.
According to the council, the original offences took place in October and November 2009 when the vehicles were stopped for inspection by council enforcement staff and the police.
Authority officers found Woodcock had permitted an unlicensed vehicle and driver to work for the company and carry out private hire work without the appropriate licences, which invalidated his insurance.
Woodcock pleaded guilty to all offences at Barnsley Magistrates' Court earlier this month and was fined 1,250. He was disqualified from driving for six months and received six points on his driving licence.
Woodcock was also ordered to pay a contribution towards prosecution costs in the sum of 500 and to pay a victim surcharge of 15.
The chairman of the licensing board,which is responsible for taxis, Coun Charles Wraith, said: "I am extremely concerned that a private hire operator in Barnsley would systematically and willfully ignore the licensing regime and put his customers at risk by using unlicensed drivers and vehicles.
"All licensed vehicles are subjected to regular safety checks by the council's own vehicle examiners and licensed drivers are thoroughly checked and vetted to ensure that they are fit and proper to transport members of the public in a safe manner."