The Serious Fraud Office spent $195,000 on public relations advice in one year.
Another $210,000 was paid to one private investigation firm and $205,000 to a company giving "strategic policy advice and research".
The total bill for consultants and contractors was nearly $1.2 million in the 2011/12 financial year, according to figures obtained under the Official Information Act.
The cost is slightly down on the record $1.3 million spent in the previous year, which the SFO said was the result of hiring forensic accountants, lawyers and investigators to help with a large number of finance company cases.
At the time, the white-collar crime agency said it would recruit more staff to reduce its reliance on external help.
Payments to forensic accounting firms have decreased by $113,000 from the 2010/11 financial year.
But the total of $1.2 million still dwarfs the $97,000 bill for consultants and contractors five years ago.
The payments to SvG Ltd, run by public relations consultant Sharon van Gulik, were $194,653 - more than any forensic accounting firm.
Only Omega Investigations ($210,744) and Martin, Jenkins & Associates ($205,632) were paid more in 2011/12.
Omega is a private investigation firm and Martin Jenkins & Associates is a Wellington consultancy group hired for "strategic policy advice and research", according to SFO office manager Mary Harris.
Spending on consultants and contractors seems to have slowed, with $238,000 paid in the first six months of the 2012/13 financial year.
"Contractors are usually only engaged where internal expertise is unavailable or at capacity," Ms Harris said.
Staff numbers are now at 52, up from 35 in 2011 after a Government cash boost of $7.5 million over three years.
Spending on consultants and contractors increased after Adam Feeley was appointed chief executive in late 2009 and made sweeping changes to the agency.
Some senior managers were made redundant and others resigned.
Mr Feeley resigned last July to become chief executive of the Queenstown Lakes District Council.
SFO consultants and contractors
July-Dec 2012: $238,755.
Top contracts 2011/12
$210,744: private investigators Omega Investigations.
$205,632: consultancy firm Martin, Jenkins & Associates.
$194,653: PR consultant SvG Ltd.