Oregon maximum assessed value calculator.

Three values on an Oregon statement

An Oregon property tax statement lists real market value, maximum assessed value and assessed value. Real market value (RMV) is what the county assessor estimates the property would sell for. Maximum assessed value (MAV) is the ceiling on what can be taxed. Assessed value (AV) is the figure your tax is actually applied to, and ORS 308.146(2) says it is the lesser of the property’s MAV and its RMV. In a market where values have risen faster than 3 percent for years, AV equals MAV and sits well below RMV.

The 3 percent rule in the statute

ORS 308.146(1) says the maximum assessed value of property equals 103 percent of the property’s assessed value from the prior year or 100 percent of the property’s maximum assessed value from the prior year, whichever is greater. The “whichever is greater” part is why the tool asks for both numbers. If last year’s AV was held below MAV by a falling market, 103 percent of AV can be lower than last year’s MAV, and the MAV does not drop. If last year’s AV equaled MAV, MAV grows exactly 3 percent. Then AV is the lesser of MAV and this year’s RMV, so a fall in RMV below MAV pulls the taxed value down.

When the rule does not apply

Subsection (3) sends several cases to ORS 308.149 through 308.166 instead: new property or new improvements, property that is partitioned or subdivided, property that is rezoned and used consistently with the rezoning, omitted property first taken into account, property that is disqualified from exemption, partial exemption or special assessment, and a lot line adjustment (with a ceiling on the total of the adjusted lots). Property subject to partial exemption or special assessment is valued under the law governing that treatment (subsection (4)). When a portion of property is destroyed or damaged by fire or an act of God, subsection (5) reduces MAV to reflect the loss for the year the reduction in RMV is shown, and subsection (6) lets an owner apply by August 1 (or within 60 days of the loss, whichever is later) to have value determined as of July 1 for damage between January 1 and July 1. A late application up to December 31 carries a fee.

Worked example

Last year’s AV was $200,000, last year’s MAV was $250,000 and this year’s RMV is $400,000. 103 percent of AV is $206,000, which is lower than last year’s MAV of $250,000, so MAV stays $250,000. AV is the lesser of $250,000 and $400,000, which is $250,000. At a total rate of $15 per $1,000 that is $3,750, against $6,000 if the tax were applied to RMV. In the other direction, if last year’s AV and MAV were both $250,000, MAV would be $257,500 this year. The tool also reports how far AV sits below RMV, which is the gap the 3 percent growth has not yet closed.

What the number is used for

Your tax is the assessed value times the rates from the taxing districts that cover the property. Because AV is usually the lower of MAV and RMV, the year-to-year change in your bill follows the MAV rule far more closely than it follows market prices. Enter the total rate from your statement, per $1,000 of assessed value, to see the tax on AV beside what it would be on RMV. Other limits on total tax that appear on a statement are not modeled here.

Limits of this page

We read ORS chapter 308 from the Oregon Legislature’s site on November 2, 2026. We could not read the Oregon Department of Revenue page, which returned a not-found error to an automated request. The tool does not model new construction adjustments, exemptions, special assessments, tax limitation categories, or the local option levies that make up your rate. It assumes the property is ordinary residential property that the county has not rezoned or divided, and the numbers you enter are correct.

Sources

Sources opened and read November 2, 2026.

• Oregon Legislature: ORS 308.146, Determination of maximum assessed value and assessed value (read November 2, 2026)