The Assessor is charged with placing a fair market value on property as of the tax date. The property tax in Missouri is “ad valorem,” meaning the taxes are based on the property value. 

The Assessor has no jurisdiction or responsibility for taxing jurisdiction budgets or establishing the tax rate.

Information maintained by this office is for assessment purposes only and should not be used to verify or transfer ownership. All maps maintained, provided and/or purchased are based on assessment information and do not represent a legal survey of the parcels shown and shall not be used for conveyance or the establishment of property boundaries.

Certificate of Non-Assessment (Tax Waiver)

A Certificate of Non-Assessment, also known as a tax waiver, may be obtained at the Assessor's Office if you did not own a vehicle in St. Charles County on January 1. The Certificate is required by the Missouri Department of Revenue to license motor vehicles or obtain a business license in St. Charles County. Learn more about requirements for the Certificate of Non-Assessment.

Filing an Assessment

Does your personal property account on the Collector of Revenue website show a zero balance due? If so, the Assessor’s Office may not have received your Personal Property Assessment for that tax year. Please visit the Assessor’s Office to file your assessment(s) or complete the assessment form online for the tax year(s) needed.

The assessment form must be filed by March 1 every year. This process needs to be completed annually to keep your personal property account active. At the beginning of every year, you will receive a new form in the mail to complete. After receiving the form, you may file the assessment online or return it to the Assessor’s Office.

If you do not file an assessment form each year, you will not receive a tax bill from the Collector of Revenue for that tax year. This may delay your ability to register your vehicle in the future.


Tax Bills

Your tax bill is comprised of three key components:

  • Assessment Authority
  • Taxing Authority
  • Collection Authority

Assessment Authority

The assessment authority (Assessor’s Office) is responsible for establishing the fair market value of all property within St. Charles County as of the tax date. This assures the tax burden is distributed fairly among those responsible for payment.

Taxing Authority

The taxing authority (school, city, fire districts, etc.) establishes the tax rate based on the budgetary requirements needed to appropriately fund the services provided within their jurisdiction.

Collection Authority

The collection authority (Collector of Revenue’s Office) is responsible for collecting the amount of tax assigned to each property owner.