1. Check how a lower value would affect your bill
Your statement lists a real market value (the county’s estimate of your property’s value on January 1, 2026) and an assessed value. A lower market value can lower your tax in two ways, and neither is guaranteed. If the value the board sets falls below your property’s maximum assessed value, your assessed value drops to that lower value. Separately, even when assessed value does not change, a lower market value lowers the Measure 5 limits on the general government and school portions of the tax, which can reduce the tax on a property that is in compression or would become compressed at the lower value. A property that is not in compression on the current bill can become compressed after a supported reduction, so the limits have to be recomputed at the proposed value, not read from the current bill. Bond taxes are outside the Measure 5 limits, so compression does not reduce them; a change in assessed value can still affect them. If neither path applies, a lower value may not change your bill. The full article walks through both paths with an illustration.
This guide focuses on appeals of real market value, the value my service handles. Oregon also allows appeals of some other values, with exceptions listed in the Department of Revenue’s appeal guide. Complaints about tax rates or levies are outside the board’s value decision.
2. Gather evidence of value on January 1, 2026
The board wants evidence of what your property was worth on January 1, 2026. Recent sales of comparable homes near that date are the usual evidence, along with anything specific to your property that the county may have missed, such as needed repairs. The county recommends sending evidence in advance. If evidence arrives fewer than ten days before the hearing, the board may continue (postpone) the hearing.
3. File with Clackamas County by December 31, 2026
- Use Clackamas County’s own petition and authorization forms, not the generic state versions.
- File a separate petition for each tax account.
- Send five copies of your petition and five copies of all evidence.
- Mail it with a U.S. Postal Service postmark (not a postage meter date) on or before December 31, 2026, or make sure the county’s Oregon City office receives it by 5 p.m. Pacific time on December 31.
Filing fee: Clackamas County does not list a filing fee, and the amount, if any, is being confirmed. Check with the county before you file.
4. If someone represents you
You can file your own appeal. Oregon law (ORS 309.100) also allows a licensed real estate broker to represent an owner before the appeals board with the owner’s written authorization. If someone represents you, use the county’s own authorization form.
5. The hearing and the decision
The Clackamas County Property Value Appeals Board holds hearings, expected from February through April 15, 2027; the county’s notice sets your date. You or your representative present the case, and the board sends its decision in writing. If it lowers your value, the change applies to the 2026-27 tax year. No result is guaranteed. A further appeal to the Oregon Tax Court is a separate step with its own deadline and filing fee.
Want me to handle it?
I prepare and file the appeal and represent you at the hearing. You pay my fee only if your taxes go down. My fee is 22.5% of your 2026-27 tax savings, only if the appeal lowers your taxes, when the last required client signature on the agreement is completed by December 20, 2026 (Pacific time). When the last required client signature is completed on or after December 21, 2026 (Pacific time), the appeal is a holiday rush and my fee is 50% of your 2026-27 tax savings, again only if the appeal lowers your taxes. Your rate is set by the date of that signature and does not change after that. If the appeal does not lower your taxes, you owe me nothing. Any county filing fee is separate and is owed whatever the outcome.
December 31 is the county’s filing deadline, not my intake deadline. Before I can file, the agreement and authorization have to be signed, the packet prepared and reviewed, any county fee paid and the filing mailed or delivered, so please contact me well before the end of December. A request that arrives in the last days of the month may not leave enough time to file.
See my Clackamas County property tax appeal page.
More: property tax appeal FAQ · guides for Multnomah County and Washington County
This page explains the general process; it is not legal or tax advice, and county rules can change. The appeals board decides every appeal, and no result is guaranteed. County rules checked October 2026. Nathan Austin Property Tax Appeal is Nathan Austin’s own business. Nathan Austin, Oregon licensed real estate broker #201244900.