Most people picture Maricopa County as the Phoenix metro, but more than half of it is federal land and much of the private land outside the cities is unincorporated desert: Tonopah, Wintersburg, Arlington, Wittmann, Morristown, Rainbow Valley and the land west of the White Tanks. If your parcel is out there, the county — not a city — sets the zoning, and the county's area plans describe what it expects to happen next.
Water is the single biggest variable in this county's land values right now. In 2023 ADWR published a groundwater model for the Hassayampa sub-basin west of the White Tank Mountains and concluded it could not approve new subdivisions there that depend on groundwater. That decision did not stop anyone from using an existing domestic well or building a single home, but it changed how large-scale buyers look at raw acreage in the far West Valley. A parcel's position relative to the Phoenix AMA boundary, the Hassayampa sub-basin and the Harquahala INA is now one of the first things a serious buyer checks.
The county assessor publishes parcel boundaries, size and full cash value for every parcel, and the recorder's document search shows deeds and easements. Both are linked below. Our research tool pulls the assessor's parcel record, FEMA flood zone and ADWR water designation for any Maricopa County address or APN in a few seconds.
What the public record says about Maricopa County
- County seat and size. Maricopa County's seat is Phoenix. It counted 4,420,568 residents in the 2020 Census across 9,201.79 square miles of land. Source
- Groundwater designation. Maricopa County contains parts of the Phoenix and Pinal Active Management Areas and the Harquahala Irrigation Non-Expansion Area. Which one applies depends on the parcel, not the county. Source
- Who owns the land. Maricopa County is 52% federal, 30% private, 13% state trust and 4% tribal land. Source
- Hassayampa sub-basin. ADWR's groundwater model for the Hassayampa sub-basin, west of the White Tank Mountains, found 4.4 million acre-feet of unmet demand over 100 years, and ADWR said it cannot approve new subdivisions there that rely on groundwater. Source
- County comprehensive plan. Maricopa County's comprehensive plan, Framework 2040, was approved on 20 May 2026. Area plans include Tonopah/Arlington, Rainbow Valley, Daisy Mountain/New River, Rio Verde Foothills and White Tanks/Grand Avenue. Source
Water and wells
Maricopa County contains parts of the Phoenix and Pinal Active Management Areas and the Harquahala Irrigation Non-Expansion Area. Which one applies depends on the parcel, not the county. Whether a particular parcel is inside a boundary is a map question, not a county question — the parcel research tool checks ADWR's boundary layer for the exact parcel, and the well lookup guide shows how to find any registered well on it.
Land markets we cover in Maricopa County
- Tonopah Maricopa County (unincorporated)
- Buckeye City of Buckeye inside city limits; Maricopa County outside
County offices for land research
These are the offices that hold the records a buyer, title company or attorney will ask about. Links marked unchecked link point to official county domains we have not yet opened ourselves.
| Assessor | www.mcassessor.maricopa.gov unchecked link |
|---|---|
| GIS / parcel maps | www.maricopa.gov unchecked link |
| Recorder (deeds, easements) | recorder.maricopa.gov |
| Treasurer (property tax) | treasurer.maricopa.gov unchecked link |
| Planning & zoning | www.maricopa.gov unchecked link |
| Long-range / area plans | www.maricopa.gov |
Look up a parcel in Maricopa County
Enter an address or assessor parcel number. We pull the parcel record, FEMA flood zone, ADWR water designation and elevation from public sources and label where each one came from.
Sources
- County seat and size — census.gov
- Groundwater designation — wrrc.arizona.edu
- Hassayampa sub-basin — azwater.gov
- County comprehensive plan — maricopa.gov
Checked 2026-10-02. Links go to the agency or publication named.
General information, not legal, tax or survey advice. First 48 Offers LLC is a real estate investment company that buys land. It is not a law firm, brokerage, surveyor or title company. Arizona statutes, county procedures and agency boundaries change, and every parcel turns on its own facts. Verify anything important with the county, the agency named, or an Arizona attorney before relying on it.