Panetta has come home to Monterey at least 27 times in a military jet since he became Pentagon chief last July. Panetta can't fly commercial because he needs to be reachable when traveling.
Each round trip, which is about 10 hours, costs about $32,000. He has reimbursed the Treasury about $17,000 for the travel, based on a government formula, or about $630 per round trip.
Based on fuel and other operating expenses for his Air Force plane, the 27 trips have cost the government as much as $860,000.
Panetta says he regrets the cost to taxpayers and is looking for savings, but he says it's important "just to get your mind straight and your perspective straight."
Typically Panetta flies on an Air Force C-37 - somewhat comparable to a Gulfstream jet - which is the lowest-cost aircraft that can carry the necessary communications equipment.
Panetta said he'd try to find some savings, but didn't specify how.
"I am trying to look at what are ... the alternatives here that I can look at that might possibly be able to save funds and, at the same time, be able to fulfill my responsibilities, not only to my job, but to my family," he said during a Pentagon briefing Monday.
The Associated Press contributed to this report.