BOISE, Idaho — When property value assessments were sent out this past May, many Ada County residents saw their home values go up.

In the North End, the median assessed value jumped by more than 18%. On the Boise Bench, residents will experience a 20% median increase.

Ada County Assessor Robert McQuade says the market value is one of two key factors that drive up property tax bills.

"Really it's a function of supply and demand here," McQuade said. "We have a very low supply of single-family residential housing, a tremendous demand, and that's really what's pushing the prices up. People are moving from different areas of the country, primarily the West Coast, and they are paying cash for homes here."

McQuade says the other primary influence of increased tax bills is local taxing districts, such as a school district or city, increasing their budget every year, which is capped at 3%.

"They all can increase their budgets each year, three percent of the highest of the last year's budget," McQuade said. Plus, they can take in new construction. Often times people forget that they voted for levies and they get their tax bill and are like, why has my tax bill gone up so much."

McQuade said unless residents have noticed an obvious error, it is too late to dispute assessed home values and property tax bills.

To avoid a late fee or interest, residents must pay their bills, or an installment, by December 20.

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