​State law requires the Assessor to value all taxable property at 100% of its true and fair market value. True and fair market is the amount of money a buyer of property willing but not obligated to buy would pay a seller of property willing but not obligated to sell, taking into consideration all reasonable uses of the property. The total assessed value of a property should not exceed its true and fair market value.

The Assessor also makes determinations on other property-related matters such as current use designations, tax exemptions and deferrals for senior citizens and disabled persons, and reductions in value resulting from governmental restrictions affecting the use of property. You can find more information about these determinations on the Assessor's website. Also, see Links and Resources for additional information from other related sites.

Any property owner or taxpayer who disagrees with the assessed value or other determination of the Assessor has the right to appeal. The only way to ensure that all your rights to due process are protected is by filing a properly completed appeal petition in a timely manner with the Board. There is no fee charged for filing an appeal.

It is a conflict of interest for the Board of Equalization (BOE) to hear appeals involving property owned in whole or in part by members or employees of the BOE or the Board of County Commissioners (BOCC), or any person related to a member of the BOE or the BOCC by blood or marriage. WAC 458-14-146 If the property owner(s) are related to a member of the Board of Equalization, BOE staff, a member of the Board of County Commissioners, or the Commissioners’ staff by blood or marriage, please contact the BOE Clerk for further instructions before filing your petition.

Thurston County is on an annual revaluation cycle. This means that every property in the County is revalued each year. The Assessor’s Office mails Valuation Notices to property owners every year. The notice will indicate the assessed values of the land and structures and, if applicable, current use land and senior citizen/disabled person frozen values. Notices of other determinations are mailed by the Assessor as these decisions are made by the Assessor’s Office.

If you believe the assessed value of your property is not correct, you may want to review your account information with the Assessor’s staff to make sure an error has not been made. It is a good idea to check the characteristics the Assessor lists for your property to make sure that important features (such as the property’s parcel size, square footage of the improvements, zoning, waterfront feet, view, topography, steep slope hazard, high groundwater, flooded area) are accurately reflected in the Assessor’s records. If errors are discovered, the Assessor may be able to correct the data and the assessment without an appeal to the Board.

It is important to note that once the Assessor certifies the assessment rolls, the Assessor and his staff have no authority to make changes to your assessed values except under limited circumstances, such as a change in land use designation or manifest errors. (See FAQ for definition of manifest error.) To preserve your appeal rights, you should file your petition with the Board before the appeal deadline. You may withdraw your appeal at any time if you later resolve your issues with the Assessor’s Office, or for any other reason.

​The deadline for filing an appeal is the latter of (a) July 1 of the current assessment year, or (b) within 60 days of the date the Assessor mailed the Valuation Notice or other determination. Due to the timing of the Assessor’s Valuation Notices, in most cases, the filing deadline will be 60 days from the mailing date of your notice. Your properly completed appeal petition must be postmarked by the U.S. Postal Service or received in the Board’s office by 4 p.m. on the appeal deadline date.

The prescribed petition form must be used. The Board accepts hard copies, as well as electronic copies submitted only through the NEW Petition link under Filing Electronic Submissions on the home page of the BOE website. The Board does not accept appeals via email or fax. A letter, email or phone call is not acceptable as a substitute for the petition form. You can find more information on downloading and completing a petition at Preparing An Appeal and BOE Forms. 

The law allows late filing of petitions in some circumstances. For example, a late filing waiver may be granted if you receive incorrect written advice regarding filing requirements from a member of the Board of Equalization, BOE staff, the Assessor, or the Assessor’s staff. These are more fully discussed in FAQ. 

• ​The Board’s Clerk will review your petition upon receipt to determine whether it is complete and timely filed. The Board does not routinely acknowledge receipt of appeal petitions filed. However, you will be notified if your petition is denied, untimely filed, or incomplete. If your petition is incomplete or further information is needed, you will be given the opportunity to provide the required information. Once a timely and properly completed petition is submitted, it is assigned a petition number, scanned into the County’s system, and electronically shared with the Assessor's office.
• If you requested valuation information from the Assessor by checking the "request information" box in Section 3 of the petition form or by contacting the Assessor’s Office, the Assessor must make available to you the information used in valuing your property. Comparable sales data are typically included, but if valuation criteria other than comparable sales were used, the Assessor must provide you with that information as well. The Assessor is required to provide all such valuation information to you and the Board by the earlier of (a) 60 days of your request or (b) at least 21 business days before the Board of Equalization’s hearing.
• After your petition is filed, the Assessor’s staff will review your petition and may contact you. Although you are not obligated to do so, both you and the Assessor are encouraged to exchange valuation information and supporting evidence. This gives both parties the opportunity to resolve the dispute prior to a hearing before the Board. Based on the evidence that you provide, the Assessor may choose to recommend an adjustment in the assessed value or to settle the appeal with you through a Stipulated Agreement. If the Petitioner agrees with the Assessor’s recommended value, the need for a hearing will likely be eliminated. If a signed Stipulation Agreement is executed by both parties, the petition is withdrawn and no hearing will take place.
• Appeals resulting from Requests for Reconvening must be heard by the Board of Equalization. The BOE must determine the true and fair market value for these appeals, even if the parties agree. These reconvene appeals may not be stipulated between the parties. (See #6 in FAQ) 
• If an agreement on the true and fair market value of your property is not reached, the Board will schedule a hearing. How soon the Board of Equalization will be able to hear your appeal is largely dependent on the number of appeals filed. The Board’s Clerk will send you a written hearing notice at least 22 business days before the hearing date. The Assessor will usually mail a written Response to the Petitioner at least 21 business days before the scheduled hearing. The Board of Equalization will also receive a copy of the Assessor’s Response. If you do not receive the Assessor’s written Response at least 10 business days before the hearing, please contact the Board’s Clerk.
• You are encouraged to submit evidence supporting your estimate of the property’s valuation. By statute, the value placed on your property by the Assessor is presumed to be correct. The burden of proof is on the Petitioner to provide clear, cogent and compelling evidence that the Assessor’s value is incorrect. The Board of Equalization is very open to hearing Petitioner’s concerns, but cannot find in your favor if you do not provide evidence. All documentary evidence, including photographs, graphs and charts, must be postmarked or received by both the Board of Equalization and the Assessor’s Office at least 21 business days before your scheduled hearing date. These are more fully discussed in Preparing An Appeal. 
• The Board of Equalization allots 10 minutes per party for residential petitions and 15 minutes per party for commercial and industrial petitions.
• Board of Equalization’s hearings have been held remotely via a conference call format since the start of the Covid pandemic, however, future in-person hearings will take place in the BOE Hearing Room at 3000 Pacific Avenue, Room 244, Olympia, WA 98501. The BOE Hearing Room is wheelchair accessible. To request disability accommodations, call the Reasonable Accommodation Coordinator at least 3 days prior to the meeting at 360-786-5440. Persons with speech or hearing disabilities may call via Washington Relay: 711 or 1-800-833-6388.
• The Board of Equalization offers teleconference hearings for Petitioners who are out of the county or who need reasonable accommodation due to illness or disability. Please contact the BOE Clerk to request a teleconference hearing.
• After the hearing concludes, the Board members discuss the petitions and the evidence presented in closed Executive Session before making their decisions. The Board’s written decision will be mailed to the parties, usually within 30 to 45 days of the hearing date.
• If either the Petitioner or the Assessor does not agree with the Board of Equalization’s decision, either party may appeal to the Washington State Board of Tax Appeals within 30 days of the date that the BOE’s decision was mailed. These are more fully discussed in FAQ. 
• To avoid accruing interest and penalty fees, Petitioners should pay property taxes when due. Any subsequent valuation changes will be addressed by the Treasurer's Office with either a corrected property tax statement or a refund. You may also pay your taxes under protest and petition the Superior Court for a refund by filing a lawsuit under chapter 84.68 RCW.