The Metropolitan Police revealed that it spent £673 watching the show in case of a confidentiality breach, having warned Channel 5 of the risks posed by featuring former detective Daniel Neal.
The figure was released in response to a freedom of information request.
"The estimated cost to review Big Brother is £673 (as at 17/07/2013) based on overtime costs and amendments in working hours," the Met said.
"No further overtime costs are anticipated to be experienced."
Just prior to quitting the police to enter the Big Brother house, Dan Neal worked on Operation Yewtree - which has been investigating historic sex abuse, sparked by the Savile allegations.
Prior to the show's launch, Scotland Yard said it had made the broadcaster "fully aware of potential risks and their responsibility to live investigations".
A spokesman added: ''All officers joining the MPS and leaving the MPS are required to sign the Official Secrets Act.''
Channel 5 said at the time that "extensive procedures" were in place to ensure that nothing would be broadcast which would breach confidentiality, invade the privacy of others, or result in libel or contempt of court.
Dan Neal had been a police officer for 10 years and was evicted from the Big Brother House on 26 July - the fifth person to leave this year's Secrets and Lies themed series.