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Preparing your appeal

Preparing your appeal


Remember, the issue before the Board is the market value of your property consistent with Washington State’s 100% market value standard. Accordingly, you will need to furnish evidence that demonstrates that the Assessor’s valuation exceeds your property’s fair market value. Successful forms of evidence include:

  • comparable sales and/or sales of the subject property;
  • contractor estimates of costs to repair building or land defects;
  • letters or documents from government agencies and/or experts regarding development limitations;
  • deeds describing easements that impact value;
  • independent appraisals;
  • photographs of features or conditions that you believe diminish your property’s market value;
  • maps showing proximity to high traffic areas, access limitations, etc.

When gathering evidence and formulating arguments, it is important to keep in mind that, by law, the Assessor is presumed to be correct. The burden of proof is on you to show that the Assessor’s determination is incorrect. Convincing evidence is the key.

Comparable Sales

Sales of the subject property and/or comparable properties are the foundation of our State’s market value standard. Accordingly, comparable sales typically provide the best indicators of market value. [RCW 84.40.030] This is particularly true for residential properties. The best comparables are sales located in your neighborhood, with similar land and improvement features, which sold closest to the valuation date at issue. Assistance in finding comparable sales is available on the Assessor’s website and their Public Information Office, 206-296-7300; and in the Tax Advisors Office (for residential properties only), 206-477-1060. Realtors and title companies may also be resources for comparable sales.

Comparing Comparable Sales

Comparable properties do not have to exactly match your property. Look for sales that are most similar, note their differences, and identify superior and inferior property features. This comparison process should enable you to determine whether your property would sell for more than or less than the price paid for each selected sale, leading you to a market value estimate.

Market Timing

According to State law, the Assessor must base assessed valuations as of January 1st of each assessment year. For example, if you are appealing a 2019 assessment year valuation, for taxes payable in 2020, the valuation date at issue is January 1, 2019. From a market timing standpoint, the Board gives comparable sales occurring closest to this date most weight.  Sales that occurred before the valuation date are preferred.