Do you know your Assessor's Parcel Number (APN)?
Go to the Maricopa County Treasurer's website and input the number in the Parcel Inquiry search field and click "Go to my Parcel".
Continue to Step 2
Visit the Maricopa County Assessor's website, where you can search for the property by owner name or address.
Find the property in question on the search results page. The first column lists the parcel number and is also the link you'll click to go to the parcel details page.
On the details page, you will see a navigation link called "Taxes" which will take you directly to the Treasurer's information page for that parcel. (Go to Step 2)
Look for the 'Tax Due' section, and click on the link for (Year) Tax Details
On the Tax Details page, you will find a section for Special Tax Districts. This will list all the Tax Districts (including County Improvement Districts) that the property may be a part of.