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Online using eAppeals or by mailing a completed petition form to the Board.  Please submit separate petitions for each parcel.

The Assessor’s office mails valuation change notices each year between May and November of the assessment year. Your assessment will determine the amount of taxes you pay in the following year.  You can appeal your assessment once you have received your valuation notice.  Petitions must be postmarked by the later of July 1st of the assessment year* OR within sixty (60) calendar days after the date of the value change notice (or other notice of determination).  {WAC 458-14-056(2) and WAC 458-14-056(4)}  

To lookup the appeal filing due date for your specific property, go to:, and enter in your property address or parcel.  Once you have selected your property, your appeal due date will be shown.  If the year for the due date displayed still shows 2018, then your 2019 assessment value change notice has not yet been sent.  Please wait to file appeal your 2019 assessment appeal until after you receive your 2019 valuation change notice.

*Assessment year is the year before the tax is due (ex. 2019 assessment determines taxes payable in 2020, thus the 2019 assessment year corresponds to the 2020 tax year).  Under very limited conditions, late petitions or appeals for previous assessment years may be accepted. {WAC 458-14-056; 458-14-127}


Yes!  The Assessor revalues properties each year, which means you must file a new complete petition to protect your appeal rights.  It is important to keep in mind that information submitted in a previous year’s appeal remains as part of the permanent record for that petition.  If you feel the information is still pertinent to the current year’s appeal, you may re-submit a copy of this data with your new petition.

A petition form for each parcel must include the following information:

  1. Assessor’s parcel number
  2. Taxpayer name and address
  3. Taxpayer’s representative, if applicable (must include power of attorney)
  4. Property description to include property address, parcel size, zoning, and general building information
  5. Value as listed by the Assessor
  6. Your opinion of value
  7. Specific reasons why you believe the Assessor’s value does not reflect the true and fair market value of your property. Your petition must include sufficient information or statements to apprise the Board and the Assessor of the reasons why you believe the Assessor’s determination is incorrect. Assessment comparisons of other properties, percentage of value increases, personal hardship, amount of tax, and other matters unrelated to market value cannot be considered. {WAC 458-14-056(5)}
  8. Taxpayer’s signature and date
  9. Attach a copy of the Assessor’s revaluation change notice or other determination notice.

The Board cannot consider incomplete petitions.

Remember, the issue before the Board is the market value of your property.  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; and 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.  Evidence must be “clear, cogent and convincing”.  {WAC 458-14-046(4)}

Evidence is due twenty-one (21) business days before the hearing. If either the assessor or taxpayer fails to submit evidence by the due date, the board may take any of the following actions:

(a) If there is no objection by either party, consider the new evidence provided by either party and proceed with the hearing;

(b) If there is an objection by either party to the failure of the other party to comply with the requirements of this rule, the board may:

(i) Refuse to consider evidence that was not timely submitted;

(ii) Postpone the hearing for a definitive time period designated by the board, to provide the parties an opportunity to review all evidence; or

(iii) Proceed with the hearing but allow the parties to submit new evidence to the board and to the other party after the hearing is concluded. The new evidence must be submitted within a definitive time period designated by the board, and must be provided to each party with an adequate opportunity to rebut or comment on the new evidence prior to the board's decision. {WAC 458-14-066(4)}

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.  For free assistance in finding comparable contact the Property Tax Advisor’s Office (for residential properties only) by calling 206-477-1060 or by emailing   Alternatively, you may want to hire an appraiser or consult with a realtor.  These type of service providers will generally charge some type of fee.

According to State law, the Assessor must base his 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 sales occurring closest to this date most weight.  {WAC 458-14-087}
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.

For the purposes of filing a complete appeal, as long as your petition includes sufficient information or statements to apprise the Board and the Assessor of the reasons why you believe the Assessor’s determination is incorrect, it is not necessary to include all the evidence you intend to use at your hearing.  While it is recommended that you provide the evidence you will use as early as possible, additional evidence may be submitted up to twenty-one (21) business days before your hearing. {WAC 458-14-056(5)}

The Board schedules hearings on a first come, first served basis.  Accordingly, the scheduling of your hearing will depend on the volume of appeals and the timing of your petition filing.  You will be notified by mail of your hearing date approximately 45 days in advance.  If the date of the hearing conflicts with your schedule, we can reschedule your hearing if you notify us within s (7) business days of the mailing date on your scheduling notice.  If necessary or requested, your hearing may be held telephonically.

The hearing is an informal review where property owners may represent themselves without having to pay someone to argue their case. You and the Assessor's representative will have the opportunity to give oral testimony and review your previously submitted arguments and evidence. Each party will have the opportunity to question and rebut the other party's arguments and evidence. One or two hearing examiners/ board members typically preside over the hearing. The Board allows 40 minutes for each appeal.

The timely submission of evidence by both parties is essential to the fair hearings process.  RCW 84.48.150 sets forth the timing requirements for each party, stating: 1) the Assessor must provide valuation information to the Taxpayer and to the Board at least twenty-one (21) business days prior to the hearing; and 2) the Taxpayer must provide valuation information to the Board at least twenty-one (21) business days prior to the hearing. Valuation information and documentary evidence includes, but is not limited to: comparable sales; income data & analysis; construction cost analysis; independent appraisals; contractor estimates of costs to repair building or land defects; documents delineating development limitations or easements; photos; maps; etc. If you miss the 21 business day deadline, late evidence may be submitted at the hearing; however, it will be subject to the late evidence process where the Assessor may object to the Board’s acceptance of it.  Acceptance of any late evidence will only be made at the discretion of the Board.  The Board encourages both parties to exchange evidence well in advance of the 21 business day deadline.

Decisions will be issued within forty-five (45) calendar days of the hearing.  If you do not receive your decision within forty-five (45) days of your hearing, please contact our office by emailing to request a copy
Approximately 25% of the property values appealed to the Board result in some type of reduction.  Compelling market-based evidence is the key.

Either the Appellant or the Assessor may appeal the Board’s decision to the State Board of Tax Appeals. An appeal must be filed with the State Board within thirty (30) calendar days of the mailing date of our Board’s decision. Appeal forms are available at the Board of Tax Appeals website ( or by phone at 360-753-5446. These forms are also available by contacting our office. {WAC 458-14-170(1)}

It is important to pay your taxes by the deadline in order to avoid interest and penalties.
If the Board decreases your value, the Assessor’s records will be adjusted and the Treasurer’s Office will either 1) send a revised tax statement if the decision occurs before April 30th or October 31st of the tax year, or 2) issue a refund if your full year’s taxes have already been paid. {WAC 458-14-116(3)} This process may take a couple of months to complete.