State officials project that Ohio will have a deficit of at least $600 million for the budget year that ends next month.
Tax Commissioner Richard Levin says April tax revenue came in $322 million short of what was expected. For the fiscal year through last month, tax revenue was $397 million short of projections.
The state's Office of Budget and Management says that means the current budget will end with a hole that could reach $900 million or more.
Some fear the state will be forced to use its $950 million rainy-day fund to plug the hole. Lawmakers have been planning to use the money to help balance the next two-year budget.
Gov. Ted Strickland's administration has already trimmed $1.9 billion from the current budget by using cuts and accounting measures.