Introduction to GIS and TCA Data

All Idaho property lies within a combination of taxing districts. When taxing district jurisdictional boundaries overlap, they form a unique entity known as a Tax Code Area (TCA).

Taxing districts submit boundary changes and annexations to the Idaho State Tax Commission throughout the year. The GIS staff maps these district boundary changes and assigns the correct Tax Code Area (TCA) for the upcoming year.

District boundary changes and annexations submitted to the Tax Commission throughout a calendar year will actually take effect during the next calendar year. For example: requests submitted to the Tax Commission during the calendar year 2015 will take effect in the calendar year 2016.

You can view and download Tax Code Area data and Tax District maps.

Free software is available for viewing the GIS data files. Printed maps can be ordered by completing and mailing this form: