This story has been updated.

When Fulton County property owners got notices of their property values last week, many were surprised by what wasn't there.

The notices show estimated taxes based on new property values, but all don't take into account every new homestead exemption that voters passed last fall, which could reduce the tax bill for many.

The exemptions set a 3 percent cap on value increases for tax purposes for Fulton County schools and the cities of Alpharetta, Johns Creek, Milton, Mountain Park and Roswell. In Atlanta, taxable values can't rise more than 2.6 percent each year for owner-occupied homes.

VIDEO: Previous coverage of Fulton taxes

Channel 2's Richard Belcher reports

The caps aren't based on current values for many homeowners, but on the value their property had in 2016, 2017 or 2018— whichever was lowest.

That base value is what’s missing from the latest property-value notices, and has caused confusion for many homeowners. DeWayne Pinkney, the deputy chief appraiser, said the lowest-value year is calculated automatically in homestead exemptions, but that number isn’t reflected in the property notices.

It is, however, part of the math used to create new school and city homestead exemptions that didn’t appear on previous notices.

Additionally, residents in Alpharetta, Roswell and Milton don’t see their city homestead exemption on value notices. The county doesn’t collect their city taxes, so it doesn’t include those exemptions on its own notices and hasn’t in the past.

It makes a difference for homeowners. Fulton leaders reacted to complaints that values skyrocketed in 2017 by freezing most values at 2016 levels, so last year's are substantially higher. The state — which is contesting Fulton's action — still hasn't approved the 2017 or 2018 tax digests for the county.

If the state prevails, county property owners could be required to pay more in property taxes for those two years.

This year’s tax rates still haven’t been set, and were not reflected in estimates sent with property value notices. Local taxing authorities will set rates, and tax bills will be sent, later this year.

Taxpayers have until Aug. 2 to appeal their values if they think the county's appraisals are incorrect.