Tax & Assessment


  • RCW 84 is the property tax law that governs Washington State property taxes.

The State Department of Revenue offers this free Homeowner's Guide to Property Tax PDF – It includes definitions of real property, personal property, calculating your property taxes, how to pay, and how tax rates differ.

Other Helpful Guides



From the time of statehood until the 1930’s, property tax was the only major tax supporting most state and local government programs. Today, property tax accounts for about 30 percent of total state and local taxes. It continues to be the most important revenue source for public schools, fire protection, library, park and recreation, and other special purpose districts.

How Does the Assessor Value My Property?

State law requires the Assessor’s Office to value property at 100% of its true and fair market value, according to the highest and best use of the property. The Assessor must take into consideration any situation or circumstance that would affect the negotiations between a willing buyer and a willing seller.

Market value is the amount of money that a willing and unobligated buyer is willing to pay a willing and unobligated seller. An individual sale does not automatically establish the value of a property. The assessor uses multiple sales to establish market value.

Real property is land and any improvements, such as buildings, attached to the land. The Assessor values real property using one or more of the professionally recognized appraisal methodologies. These are the market or sales comparison approach, the cost approach, the income capitalization approach, or any combination of the three approaches.


Properties are revalued annually and are physically inspected at least once every six years. After determining the value, the assessor mails property owners a “Change of Value Notice.” The notice states the new and the old values. By comparing the two values, property owners can tell whether their property has increased or decreased in value. The notice also breaks down the value between land and improvements. Valuation notices are NOT tax bills. An increase in value does not mean that next year’s property taxes will increase at a proportionate rate.

When Do I Receive a “Change of Value Notice”?

The Assessor will send you a notice when the assessed value of your property changes. In Island County the Assessor is required to physically inspect and value all real property every six years. After determining a new value, the Assessor mails the taxpayer a “Change of Value” notice. The assessed value should not exceed the market value of the property.

What If I Did Not Receive a ”Change of Value Notice”?

The Assessor is obligated to send the notice to the taxpayer whose name and address appears on the assessment rolls. Often mortgage or lending companies appear as the designated taxpayer representative on the tax rolls. You are responsible for notifying the Assessor’s Office of any address changes. You are responsible for requesting that mortgage or lending companies send copies of the notices to you.