Taxes are due within one month of the due date before interest is charged. For the July 1st tax bill the bill becomes delinquent on August 2nd. The January tax bill becomes delinquent on February 2nd. Delinquent taxes are subject to an interest rate of 1 1/2% per month ($2.00 minimum interest charge) going back to the original due date. For example, if you paid your real estate bill on August 10th, you would be subject to an interest penalty of 3.0 %.