There were also personal bank account and other details on the stick.
It did not contain information about Fidelity Life customers or their policies, Mr Jennings said.
He did not anticipate anything would happen as a result of the breach and suspected the thief had just thrown USB away.
"We just had to make sure that we informed everyone in case anything unusual did start happening with their bank accounts or any of their investments.
The employee who left the stick in his car had been with the company only a few months,
He had been stood down while the matter was reviewed, Mr Jennings said.
The company sent a letter to affected customers offering its sincerest apologies.
"I would like to assure you that the confidentiality of our clients is of the utmost importance to us and we are extremely concerned this incident occurred,'' it said.
A spokesman from the Office of the Privacy Commissioner said they had been contacted by both Fidelity Life and the Financial Markets Authority about the breach.
"We are aware of it and as far as we know Fidelity Life are following data breach guidelines,'' the spokesman said.
"They've done the right thing by telling us that it's happened and hopefully they will do everything appropriate to mitigate the damages.''
He could not comment on the potential seriousness of the breach.