After you file a property tax appeal, you may submit evidence to support your case. Evidence helps explain why you believe your property’s assessed value is incorrect.
You may submit new or additional evidence, but you do not have to. The County Board of Equalization will send us the evidence you submitted at the county level. If you want the Board of Tax Appeals to consider that evidence, you must tell us which specific items you want reviewed.
To rely on evidence you submitted to the County Board of Equalization, file a Statement of Reliance.
Check your evidence deadline
Your Prehearing Order will tell you when evidence is due. Unless the order gives a different deadline, you have 60 days from the date your appeal was acknowledged to submit new evidence.
Late evidence may not be accepted.
You must also send the county assessor an identical copy of any evidence you submit to the Board.
Send a copy to the assessor
If you send evidence to the Board, you must also send the same evidence to the county assessor.
You must send the assessor’s copy by U.S. mail or hand delivery, unless both parties agree to another delivery method.
What makes evidence helpful
Helpful evidence supports your opinion of your property’s market value. Your evidence should focus on the value of the whole property, including both the land and any buildings or improvements.
Useful evidence may include:
- Comparable sales
- Appraisals
- Photos
- Repair estimates or contractor bids
- Documents from a government agency
- Maps, property records, or other supporting documents
- Written explanations that connect your evidence to your property’s value
Show the value of the whole property
The Board considers the market value of the whole property. This means the combined value of the land and improvements, such as buildings.
Evidence about only the land value or only the building value may be helpful, but it usually does not prove the full market value of the property.
Market value is the amount your property would likely sell for on the open market. State law requires property to be assessed at 100% of its true and fair value. True and fair value means market value.
Foreclosures and short sales are usually not considered normal market sales.
There are three common ways to determine market value:
- Sales comparison approach
- Cost approach
- Income approach
You may also use a combination of these approaches.
Market evidence may include sales of your property or similar properties made within the past five years. For more information, see RCW 84.40.030(1).
Using comparable sales
Comparable sales are sales of properties that are similar to yours. For residential property appeals, comparable sales are often the best way to show market value.
Look for sales that:
- Happened within 5 years before your assessment date
- Happened as close as possible to your assessment date
- Are close to your property, such as in the same neighborhood or subdivision
- Are the same type of property, such as residential or commercial
- Are similar in size, age, condition, quality, and features
- Help show the market value of your whole property
Sales that are closest to your assessment date and most similar to your property are usually given the most weight. Sales that happened after the assessment date may be given less weight.
For each comparable sale, include:
- Parcel or account number
- Property address
- Sale date
- Sale price
- Lot size
- Square footage
- Year built
- Number of bedrooms and bathrooms, if residential
- Garage, carport, outbuildings, or other features
- Zoning
- Access issues
- Wetlands, view, waterfront, or utility access, if relevant
A map showing your property and the comparable sales may also be helpful.
You can find comparable sales information from realtors, title companies, or your county assessor’s office. The Department of Revenue has a list of county assessor websites.
The Board prefers comparable sales to be organized in a sales grid.
Download the sales grid template (.xls)
Include repair, condition, or development evidence
Repairs, condition issues, environmental impacts, or development limits may affect your property’s value. If these issues are part of your case, include documents that show what the issue is and how it affects value.
Do not just state that repairs are needed. Show what needs to be fixed and provide evidence of the cost.
Useful evidence may include:
- Photos of damage or outdated features
- Independent contractor estimates
- Repair bids
- Documents showing the work needed and the cost
- Environmental reports or related documents
- Permit denials
- Letters from a government agency explaining development restrictions
- Other official documents about limits on how the property can be used
Upgrades are different from repairs. An upgrade may improve the property, but it may not show that the assessed value is too high.
Evidence that is usually not helpful
Some information may seem relevant but may not help prove your property’s market value.
The Board generally cannot use:
- The assessed value of a neighbor’s property
- Your property’s assessed value from other years
- Complaints or past issues with the assessor’s office
- Large amounts of raw or disorganized information
A neighbor’s sale price may be useful if the property sold before the assessment date and is comparable to your property. But a neighbor’s assessed value is not enough to prove your property’s value.
Should you get an appraisal?
You may submit an appraisal if you have one. An appraisal can be helpful if it includes strong evidence and clear explanations.
The Board may consider the facts and analysis in an appraisal, such as comparable sales or income information. However, the Board must make its own decision about value. It does not have to accept the appraiser’s final value conclusion.
Organize your evidence
Organized evidence is easier to review and understand.
When preparing your evidence:
- Identify which County Board of Equalization materials you want the Board to consider.
- Group your evidence by the point it supports.
- Label each document clearly.
- Number the pages.
- Use a comparable sales grid when submitting sales information.
- Explain how each piece of evidence supports your opinion of value.
How to label evidence
Mark each page of evidence in the lower right corner.
Include:
- The party submitting the document
- The document number
- The page number
For example, if you are the appellant and you submit your third document, page 1 could be labeled: A3-1
This means:
- A = Appellant
- 3 = Document 3
- 1 = Page 1
Submit your evidence
You may submit evidence by email, mail, or fax.
Email: bta@bta.wa.gov
Mail: Board of Tax Appeals, P.O. Box 40915, Olympia, WA 98504-0915
Fax: 360-586-9020
If you have questions, contact us at bta@bta.wa.gov or call 1-866-788-5446.