Glossary · Thresholds & Valuation
County assessor
In short
The county office that sets full cash value. For a contractor it is the source of the residential threshold denominator, and the figure is public before the bid goes out.
In full
Each county's assessor values locally assessed property. By December 15 each year the assessor identifies all real property in the county subject to taxation and not valued by the Department of Revenue, determines its full cash value as of January 1 of the following year using ADOR's manuals and procedures, and lists it on the tax roll. Identification runs on aerial photography, ADOR records, building permits and other documentary sources.
Before March 1 each year the assessor notifies each owner of record of the parcel's full cash value and limited property value, if applicable. That date is not absolute: it is subject to an exception at A.R.S. § 42-13254, and the director may extend it by up to thirty days for delays caused by an act of God, flood, fire or a declared state of emergency. An extension applies to all property valued by the assessor, not to individual parcels.
For a contractor the assessor is the source of one number: the denominator in the residential alteration threshold. A.R.S. § 42-5075(S)(1)(a) points at the most recent full cash value established under title 42, chapter 13, article 2 — the article that assigns this work to assessors.
ADOR Tax Policy directed contractors to obtain that figure from the county assessor's website, which matters more than it sounds. The value is public record and can be pulled before a bid goes out, with no involvement from the property owner and no waiting on the owner's annual notice.
ADOR's response supplied Maricopa County's parcel viewer as its example. The example is illustrative only — a parcel is searchable through its own county's assessor and no other, so a Yavapai or Coconino parcel is not retrievable from Maricopa's system.
A.R.S. §§ 42-13051, 42-15101(A), 42-5075(S)(1)(a); ADOR Tax Policy information letter, 2026-08-13