Will adding an ADU raise my property taxes?

Adding an accessory dwelling unit typically does raise a property's assessed value, since it adds finished square footage and functional living space that a county assessor will factor into the next assessment. How much the tax bill actually changes depends on the assessed value increase and the millage rate the county and city set for that tax year, which varies annually. A homeowner planning an ADU should ask their county assessor's office how new construction of this kind gets valued before starting the project. Brian Beatty can help a homeowner think through that tradeoff against the rental income the ADU could generate.