By Mike Dunn

PHILADELPHIA (CBS) — Philadelphia Mayor Michael Nutter calls the citywide reassessment of property values “historic.”

About 560,000 notices were being mailed out by Philadelphia City Hall today to Philadelphia property owners (see related story).

And for many of them, it could be an early indication of a possible property tax hike.

“For the first time, our property tax system will be an accurate reflection of the real values of our properties,” the mayor said today at City Hall.

Those new “Actual Value Initiative” assessments are now in the mail, but what it means is still unclear. Mayor Nutter and City Council still need to decide on a new tax rate and what forms of relief will go to residential homeowners.

City of Philadelphia brochure about AVI (.pdf format)

Chief assessor Richie McKeithen (second from left in photo) says if you feel your assessment itself is wrong, you can file for what is called a “first-level” review, “to sort of save the actual taxpayer from having to go a formal hearing to get their assessment reviewed.”

The form to request such a review (.pdf) will be included in the assessment notice. But McKeithen warns you cannot request a review based on pure emotion, nor on ability to pay.

“We want you to file your first-level review based on honest facts: what your property is assessed, characteristics that we have on your notice for your property, is your property value equitable?”

If you have questions about the assessment, you can call the Office of Property Assessment at 215-686-9200, or go to phila.gov/opa.

If you are not satisfied with the first-level review, you will still have the option to formally appeal the assessment to the Board of Revision of Taxes.

The assessments will determine the property tax amounts due next year.