McCarthy Thielman Realty
McCarthy Thielman Realty
Brinda S. Thielman, Broker, McCarthy Thielman RealtyPhone: (602) 228-9194
Email: Brinda@BrindaThielman.com

What is a supplemental tax bill?

by Brinda S. Thielman, Broker 03/30/2025

If your property has increased or decreased in assessed value since your last tax payment, you might receive a supplemental tax bill. These are separate tax bills you need to pay in addition to your regular annual bill. If you're interested in learning more about how supplemental tax bills work, here is a short guide to the basics:

Supplemental tax bills may reflect changes to your property

Supplemental tax bills are usually the result of a supplemental assessment of your property's value. Supplemental assessments happen when you complete new construction or major rehabilitation to a home. Supplemental assessments also take place when a property changes ownership.

Supplemental tax bills can have different due dates

Supplemental tax bills are separate from your normal property tax bills. Therefore, they can arrive at any time of year regardless of your annual tax due date. It's important to take care of these payments as soon as possible to prevent issues.

Supplemental tax bills can be negative

Negative supplemental tax bills are the result of a new assessment being lower than the previous. If you receive a negative tax bill, you'll also receive a reimbursement check. The amount of the refund check will depend on the difference between assessments. Conveniently, most municipalities allow you to apply the refund amount to any other outstanding tax bill, potentially saving you thousands.

Are you planning any major construction or updates to your home? If so, you can likely expect a supplemental assessment for the changes. Keep this basic info in mind for a better understanding of your supplemental tax bill.

About the Author
Author

Brinda S. Thielman, Broker

Hi! I'm Brinda Thielman. Thank you for your interest in exploring Arizona real estate with me.

As a native Arizonian, I have seen the growth in the “Valley of the Sun” first hand. With over 30 years in the real estate industry, I know how challenging and intimidating buying and selling a home can be. That's where I come in! When I started my real estate career, I quickly found I loved every aspect of the home buying and selling process, from touring a home, researching the best mortgage loan for my clients, new construction details and even the negotiation and closing process. 

In 2015, I help found McCarthy Thielman Realty, LLC. Today it is one of the leading boutique real estate firms specializing in North Phoenix real estate.

My mission is to help you accomplish your real estate goals and dreams - "I'll Lead You Home!"