The FSA has been cracking down on various problems
Insurance customers could have been left without the cover they paid for after directors misused clients' money.
The Financial Services Authority (FSA) banned three directors of BPS Insure after the trio failed to inform the FSA of a £3m client account deficit.
The city regulator said Robert James, Stuart Lawton and Paul Adams used client money at the start of 2005 to pay the business's general expenses.
Rules state this money should be kept in a separate account.
It is relatively rare for the FSA to ban insurance company directors, but the watchdog is currently cracking down on mortgage fraud which has led to a number of people being banned from the financial services industry.
The FSA said that the three men at BPS Insure knew that they should have informed the regulator about the deficit and that they were misusing client money.
"The directors of BPS acted recklessly and without integrity. They failed to ensure that clients' money was adequately protected and undermined consumers' confidence in the insurance sector," said Jonathan Phelan, head of retail enforcement at the FSA.
"Senior managers must recognise their responsibilities - they are personally responsible and the FSA will take action against directors who fail to act appropriately when carrying out certain regulatory functions."
London-based BPS subsequently went into administration.
The three men have been banned from certain regulated financial services functions.