Accessory Dwellings

A one-stop source about accessory dwelling units, multigenerational homes, laneway houses, ADUs, granny flats, in-law units…

Property tax Calculator

Calculating the Impacts of this ADU Tax Policy Change on Your Property

We’ve built this little calculator tool to help Multnomah County homeowners understand what the possible impacts of the tax policy change are for their property.

This property tax estimator tool helps estimate what your property taxes using the Oregon Department of Revenue reMAV formula, as described here. It compares this new ‘reMAV’ method to the standard ‘improvement’ tax calculation method that was used before 2015, and is used in all other counties in Oregon besides Multnomah County.

Using this calculator, once you enter values from your recent tax bill, it will spit out the property tax calculations under the common, standard formula that Multnomah County was using until this year, as well as the property tax estimate using Department of Revenue’s re-MAV formula.

These are approximate estimates, not considering any 3% annual rise that the property taxes would normally have. You should call Multnomah County to get a more authoritative estimate.

The values that you need to use this calculator are listed on your property tax bill, which you can find online by visiting and clicking on “guest”. Type in your address eg. “100 N. Example”. Leave off “St” or “Ave” from the address. Once in, click the “Tax Summary” tab, then click the hyperlink “click to view tax bill”. That’s where the new tax records can be viewed if you don’t have your paper copy handy. Type your values in the yellow boxes. 

%d bloggers like this: