How is farmland assessed for property tax?
Farmland is assessed based on its ability to produce income (its agricultural economic value). A farm building is assessed at one-third of the value that it contributes to the farm’s productivity. Farm home sites and farm dwellings are assessed at one-third of their market value. For more information, see PTAX-1004, Illinois Property Tax System.
Note: If a farm is subdivided for development, the increase in the land's assessed value is not considered new property. Under 35 ILCS 200/18-185, new property is limited to a new improvement or an addition to an existing structure. An increase in land assessment is not new property.