Real property tax is delinquent if not paid by May 15. Foreclosure proceedings on real property begin when taxes have been delinquent for 3 years.
(*) Accounts subject to Foreclosure -
Real property tax accounts with an unpaid balance for any tax year marked with an (*) on the front of your tax statement are subject to foreclosure if not paid on or before May 15.
Property tax payments must be credited to the earliest year that taxes are due. For example, if you owe taxes for 2012, 2013, 2014 and 2015 any payment made will be first applied to 2012 and so forth.