Mueller III spent $3.2 million in the first 4½ months of his investigation into whether anyone from President Trump's team helped Russian interference with last year's presidential campaign.
Mueller's probe also caused other Justice Department components to spend about $3.5 million on work attributable to the special counsel probe, according to the report.
It's hard to make comparisons to other investigations led by specially designated prosecutors or to draw conclusions about how much Mueller will ultimately spend.
The details of the expenditures related to Mueller's investigation were laid out in a report released publicly by the special counsel's office. Reports last week said the special counsel had removed a veteran Federal Bureau of Investigation agent from his team for sending anti-Trump text messages.
The figures were revealed in a Justice Department report released Tuesday. The independent counsel spent more than $60 million over the course of that six-year inquiry into then-President Bill Clinton.
DOD acknowledges additional U.S. troops in Syria
Manning said the delay was in an effort to "get it right". "Important work remains to ensure lasting defeat" of ISIS, he said. The Pentagon first announced plans to revise the number on August 31, when they unveiled a higher troop count in Afghanistan.
Mueller's spending included $3.2 million in direct and reimbursed expenditures - including more than $1.7 million for personnel, $733,000 for equipment, $362,000 for rent and utilities, $223,000 for travel and $157,000 for contract services, such as technology services and transcripts, according to the report.
"The cost of the Mueller investigation is far more than dollars and cents", he told Reuters in an interview. Manafort and Gates have entered not guilty pleas in defense of a number of business related charges. George Papadopoulos, a former Trump campaign foreign policy adviser, made a similar plea deal with Mueller's prosecutors in October.
Last week, former national security adviser Michael Flynn pleaded guilty to lying to Federal Bureau of Investigation agents.
An investigation into President Bill Clinton by independent counsel Kenneth Starr cost about $40 million from January 24, 1994 to September 30, 1998, according to the GAO.
In a statement, the special counsel's office said it will release a similar expenditure report after March 31, 2018.