Assessment Process

Each year, the Assessor’s Office appraises all real property in the City of Trenton to determine its value for tax purposes. All assessments of real property, including land and permanently affixed structures, are based on fair market value and are equitable with the assessments of comparable properties.

The City Assessor always performs the duties of this office through accepted professional appraisal practices which lead to the valuation of the tax parcels under his/her’s jurisdiction.

Assessment Process

To determine the value of a property, the Assessor’s Office obtains and maintains many different types of information. The Assessor’s Office keeps on file a property record, listing the physical characteristics of each property and its condition.

Property selling price in the City is an important factor in determining assessment values. The Assessor’s Office regularly researches records relating to the sale of all types of properties within the city to stay abreast of the current value of real estate.

Other types of information used in determining the value of industrial, commercial, and special purpose properties can include current building replacement costs, the operating and maintenance costs of various types of property, and rental rates certain properties can be expected to earn.

Fair Market Value

The Assessor’s Office utilizes the  three universally accepted approaches in estimating market values:

Sales Comparison Approach: The most commonly used and accurate method for determining market value when adequate sales of comparable properties similar to those being appraised exist. Adjustments for differences in the properties are made, and value is estimated for the subject by comparison.

Cost Approach: This method consists of estimating the current reproduction or replacement cost of the improvements, deducting any accrued depreciation, and adding the value of the land.

Income Approach: Used most commonly for commercial properties that are bought and sold based on their earning potential. This method involves estimating the potential gross income from the property, deducting typical vacancies, collection losses and operating expenses arriving at a net operating income. The assessor uses market data that is calculated to translate the estimated future income of a property into an estimate of present day market value.

Types of Properties

Residential Properties - The sales comparison approach is commonly used in estimating the value of residential property. Due to the high volume of sales that occur for this type of property. This approach is considered the most reliable for this type of property because it reflects the balance of supply and demand in the marketplace and is based on the principle that an average buyer will not purchase property at a price higher than the selling price of similar properties.

Non-Residential - Properties-lexes, and small businesses are purchased not based on the value of the property but rather on the future earning capacity the business possesses. These properties, therefore, are most often valued by the income approach, which recognizes the relationship between the property’s value and the income it is expected to earn.

Michigan Compiled Law (MCL) 211.27a(1) Except as otherwise provided shall be assessed at 50% of its true cash value under section 3 of article IX of the state constitution of 1963.

General Duties of the City Assessor

The Assessor’s goal is to provide fair and equitable assessments to the taxpayers. Michigan Certified Assessing Officers are required to annually prepare and certify the assessment roll for the City in accordance with the General Property Tax Act and responsible for the administration of the General Property Tax Laws.

The assessor and staff must complete several tasks not limited to the following:

Locate, identify, record and establish the true cash value, assessed and taxable values of all real property subject to taxation.

Certified by the State of Michigan as a Personal Property Examiner to establish the taxable values on all taxable personal property.

Maintain descriptions of property.

Use appropriate appraisal techniques (cost approach, market approach, and also the income approach).

Assessment Roll must be prepared on or before the first Monday in March to be presented to the Board of Review by the Tuesday following the first Monday in March (MCL 211.30).

Notification of assessment increases must be prepared and sent to taxpayers 10 days prior to the first Board of Review meeting (MCL 211.30).

Assessments often must be defended before the Michigan Tax Tribunal.

Affidavits for Principal Residence Exemption (which exempt certain properties from paying the 18 mills of school operating taxes) (exemptions granted or denied by the assessor by determining eligibility for claims) and Property Transfers must be processed.

Required to preserve and keep all books, assessments rolls and other papers belonging to the office and comply with State Statutes and the Michigan Township Record Retention Schedule No. 10.

Must maintain records relevant to the assessments, including appraisal record cards, personal property records, historical assessment data, Tax Maps, and Land Value Maps consistent with the standards found in the Assessor’s Manual approved by the State Tax Commission. (MCL 41.62)

File numerous mandated forms and reports with the County Equalization Department, the State Tax Commission and the Michigan Department of Treasury.

Respond to all information requests from the public.

Present annual department budget requirements and other reports to City Council.



  1. Physical Address
    2800 Third St.
    Trenton, MI 48183

    Mailing Address
    2800 Third Street
    Attn: Assessor's Office
    Trenton, MI 48183

    Phone: 734-675-6810
    Fax: 734-675-5262

    Hours
    Monday through Friday
    8:30am - 5pm


  2. John P. Dahlquist

    City Assessor

  3. Joanie Barnett

    Deputy City Assessor