Hours of Operation:

Monday – Friday 8:30AM – 3:00PM

Contact Info:

Marcy Lawerence

108 4th Avenue

Sterling, IL 61081



Click Here for FAQ





  • Our Office is available for assistance with Senior Exemption and Senior Freeze forms. Your welcome to walk in or call us for an appointment. 
  • Senior Exemption and Freeze forms are due July 1st. You may also submit renewals to our office. 
  • Landlord Tenant Agreements are due at the county by July 1st. 


Property Tax Process Overview

It is important to note that assessment of property is just the beginning of the property tax process. The Assessor’s Office has the responsibility to value property based on market value and equity. Once the Assessor’s books are closed, those values are used by taxing bodies to actually formulate your tax bill. The Assessor’s work follows the assessment process each year and concludes with the closing of the books in the fall. Once the figures are factored by the Supervisor of Assessments and finalized by the Board of Review, the various taxing bodies begin the work of levying for their budgetary needs. Each taxing body sets its levy against the total assessed valuations within its taxing district. The funds from the levy form the budget of the taxing body for the upcoming year. Taxing district lines often cross each other and overlap; your tax bill lists the taxing bodies that collectively provide services for your area of the Township. These taxing bodies include school districts, park districts, municipalities (for incorporated areas), county (for unincorporated areas), and many others. Once each taxing body determines its budget and sets its levy, they file for their tax extension with the County Clerk. The County Clerk must calculate each taxing body’s levy against its total Equalized Assessed Valuation (EAV) to derive the tax rate. The individual tax rates for each taxing body that serves your area form your overall tax rate; you can see the elements of your tax rate listed on your tax bill. Once tax rates are set, the Treasurer begins the collection process. In Whiteside County, tax bills are usually mailed in May and are paid in two installments. The first is due sometime in June; the second is due the first part of September. The above represents a brief overview of the property tax process. The Assessor’s work provides the valuation information that serves as the basis for the process, but the Assessor has no role in the setting of tax rates or the collection of tax payments.


Tax Bills & Collection:

Taxes are paid in two installments in Whiteside County, with the first due sometime in June unless the date is extended because of late billing. The second installment is then due the first part of September. The Whiteside County Collector mails the tax bill to the taxpayers at least 30 days before the first installment is due. The tax bill may be paid at the Collector’s Office at the Whiteside County Courthouse in Morrison or any designated bank in Whiteside County or online (contact the Collector’s Office for this information 1-815-772-5196). It is the taxpayers’ responsibility to keep their address current with the Collector. If taxpayers do not receive a bill, they should inquire with the Collector.


Where Do My Taxes Go?

When reassessment notices are mailed in the fall we start getting calls from property owners whose first words are “My taxes are too high!” or “Why did you raise my taxes!” The Township Assessor does not raise your taxes. The job of the assessor is to come up with a fair market value of all the property in the township. From that fair market value, the assessment is computed as 33.33% of that value. All of the assessment’s are given to the supervisor of assessments in the county seat for equalization and then to the County Clerk. The County Clerk has been provided with all the levies from the taxing bodies and the tax rate is determined by dividing the total levy by the Equalized Assessed Value. Finally the tax rate is applied to each individual assessment to come up with individual tax bills.