The Governor's Office of Planning and Budget announced the additional $58.4 million added to the so-called "rainy day fund" on Thursday.
The additional money brings the fund up to $145.8 million, with a little more than $40 million earmarked to help Utah's schools in the case of an economic downturn or some other emergency.
Budget Director Richard Ellis called the surplus cash "a nice boost to build it up quicker than was anticipated."
The previous high for the rainy day fund was $116.4 million in the 2001 fiscal year, but a subsequent recession forced lawmakers to raid the fund to plug holes in the budget. They drained it to $19.5 million in 2002.
Since then it has inched up as the economy improved, with the biggest increases coming in the past two years.
Unless there a natural disaster or some unforeseen event stunts Utah's strong economic growth, Ellis expects the fund to continue building in the years to come.
"The government is not in the business of building up huge savings, but it should have enough to weather a few storms," said Rep. Ron Bigelow, R-West Valley City, who is the House budget chief.
The cash-heavy fund not only acts as a kind of insurance policy against recession, but allows the state to obtain better interest rates on billions of dollars of loans, known as bonds.
The budget office also affirmed earlier estimates that lawmakers have $104.8 million in excess tax money to spend when they meet again starting in January. Much of the surplus came from higher-than-expected sales and payroll tax collections. Ellis expects legislators to use the money to build new structures or roads, as they did last year with surplus funds.
While excited about the surplus, Bigelow said the state should proceed with caution. He worries that Hurricane Katrina-related devastation in the South could slow the economy nationwide.