Illinois finished the fiscal year on Sunday $6.1 billion in the red.
But Comptroller Judy Baar Topinka says that the backlog of unpaid bills to schools, agencies, hospitals and businesses is expected to grow another $1.4 billion by next month.
The state collected $1.3 billion in unexpected tax revenue this spring from residents selling assets before new tax laws took effect.
a/Illinois Comptroller Judy Baar Topinka says that money was used by lawmakers to increase spending in the budget.
She also says lawmakers might consider extending the temporary income tax hike of 2011 to cover the debt.
The comptroller's office estimates unpaid bills will rise to $7.5 billion in August and to nearly $9 billion by December.