Assessor

The Maricopa County Assessor is the county office responsible for identifying taxable property, maintaining ownership and property information, establishing property values, applying legal classifications and exemptions, and administering valuation-related services for real and personal property. This article explains how residents and property owners can search Assessor records, locate a parcel number, understand valuation information, handle classification or factual errors, file valuation appeals and claims, register rental property, work with business or mobile-home records, apply for valuation relief, and determine when another county office is responsible for a property-tax issue.

Assessor Office Responsibilities

The Maricopa County Assessor's Office annually notices and administers more than 1.8 million real and personal property parcels and accounts with a combined full cash value exceeding $1 trillion. Its work centers on the property information and valuations that become part of the county assessment roll.

The Assessor locates and identifies taxable property, identifies ownership, establishes values for property subject to taxation, lists those values on the assessment roll, assigns or maintains legal classifications, and applies qualifying exemptions. Its responsibilities cover several different types of property, including residential real estate, business personal property, and manufactured or mobile homes.

This distinction matters because the Assessor does not calculate individual property-tax bills and does not collect property taxes. Questions about a valuation, property characteristics, ownership information, legal class, exemption, or Assessor record generally belong with the Assessor. Questions about an actual property-tax bill or tax payment belong with the Maricopa County Treasurer's Office.

The Assessor's organization includes the Administrative Division, Valuation Relief Program Division, Information Technology Division, Property Ownership & Mapping Division, and Appraisal Division. Property owners do not necessarily need to identify a division before seeking assistance. The office's inquiry system routes questions based on the category and topic selected by the user.

Property and Parcel Searches

For many users, the first task is locating a property record. The Assessor's main website provides parcel and address searching, allowing users to identify the Assessor Parcel Number associated with a property and review available Assessor information.

The parcel number is also called the APN, or Assessor Parcel Number. According to the Assessor's parcel number instructions, users can search from the main page using either a name or street address. The APN appears in the first column of the search results. When several results appear, compare the owner name and property information before relying on a parcel number.

Having the correct parcel or account number is especially useful when submitting an inquiry, requesting an address-related update, reviewing a valuation, working with rental-registration records, or completing Assessor forms. A parcel number identifies the property in the Assessor's system and should not be confused with a tax-payment reference or another county department's record number.

Search Information to Prepare

Before searching or contacting the Assessor, gather the identifying information that applies to the property. Depending on the task, useful information may include:

The property owner's name.
The street address.
The Assessor Parcel Number or account number, if already known.
The property type involved in the request.
The tax year shown on a Notice of Valuation.
Supporting records when reporting a factual, ownership, classification, or valuation issue.

Using the correct parcel is particularly important for owners with multiple properties or similarly named entities. A mailing-address issue, residential classification request, valuation appeal, and business personal property account may each require different supporting information even when they involve the same owner.

Property Values and Taxable Values

A common source of confusion is the difference between Full Cash Value and Limited Property Value. The Assessor describes Full Cash Value, or FCV, as its estimate of a property's market value. Limited Property Value, or LPV, is generally the value used as the basis for Arizona property taxation and cannot exceed the property's Full Cash Value.

The Assessor's Limited Property Value explanation describes two calculation methods, commonly referred to as Rule A and Rule B.

Rule A Valuations

Rule A applies to most properties that have not experienced a statutory change requiring a different calculation. Under Rule A, LPV can generally increase by as much as 5 percent per year, provided it does not exceed Full Cash Value.

This means a property's market-related value and taxable value can move differently. A decline in Full Cash Value does not automatically mean LPV will decline by the same amount. Likewise, changes in LPV do not by themselves state what the final property-tax bill will be.

Rule B Valuations

Rule B applies when a statutory trigger affects the property. Examples identified by the Assessor include new construction or major improvements, demolition, parcel splits or lot combinations, changes in property use, and the loss of certain special valuation programs.

Under Rule B, the Assessor uses a percentage derived from similar properties in the same classification and applies that percentage to the property's Full Cash Value. The resulting LPV may be higher, lower, or similar to the property's prior LPV. Rule B therefore should not be assumed to automatically produce an increase.

From LPV to Assessed Value

Assessed Value is determined by multiplying Limited Property Value by the assessment ratio established under Arizona law. The Assessor provides an example in which an LPV of $58,702 multiplied by a 10 percent assessment ratio results in an Assessed Value of $5,870. The Treasurer uses assessed values when calculating property taxes.

Property owners reviewing a valuation should therefore distinguish among Full Cash Value, Limited Property Value, and Assessed Value rather than treating them as interchangeable figures.

Notices of Valuation

The Assessor sends Notices of Valuation showing how property is valued and classified for tax purposes. For residential real property, the 2026 calendar states that the Assessor mailed the 2027 Notice of Valuation on February 20, 2026.

When reviewing a notice, compare the valuation and classification with the underlying issue you believe is incorrect. The correct filing process depends on the type of problem. The Assessor separates valuation or classification disagreements, factual or multi-year classification errors, and recent primary-residence classification changes into different procedures.

Three Different Correction Paths

The Assessor's valuation dispute instructions identify three primary filing paths for real property:

Appeal: Used when the owner disputes the value or classification shown on the applicable Notice of Valuation.

Notice of Claim: Used for factual errors, such as incorrect square footage or year built, or certain classification errors affecting the current or prior tax years covered by the claim process.

Residential Legal Class Change: Used when a property recently became the owner's primary residence and the owner wants the legal classification updated.

Selecting the wrong procedure can create unnecessary delays. A valuation disagreement is not the same as correcting an objective property characteristic, and a primary-residence classification request has its own documentation requirements.

Real Property Appeals

For the 2027 real-property Notice of Valuation mailed February 20, 2026, the deadline for an Assessor-level Petition for Review of Real Property Valuation was April 21, 2026. The Assessor states that online appeals are closed for that appeal season.

A real-property appeal is appropriate when an owner believes the property's value or classification on the notice is incorrect. Examples include a Full Cash Value that the owner believes does not reflect market value or a property classified as a rental when it is occupied full-time as the owner's residence.

The Assessor requires documentation supporting the owner's position. Examples given by the office include recent appraisals, comparable sales, and legal-classification documentation. Appeals submitted without supporting documentation may be denied.

The residential property calendar states that August 15, 2026 was the Assessor's deadline to rule on assessment appeal requests. A property owner who is dissatisfied with the Assessor's decision may file with the State Board of Equalization within 25 days from the date of the Assessor's appeal decision.

Notices of Claim

A Notice of Claim addresses a different type of problem. The Assessor indicates that this procedure may be used for a factual or classification error involving the current or past three tax years identified on its 2026 appeals page: 2026, 2025, 2024, or 2023.

Examples include a property record showing 3,000 square feet when the actual property contains 2,000 square feet, or a qualifying classification that has been incorrect for multiple years. Evidence is required. The Assessor identifies items such as blueprints, permits, ownership records, and legal-classification proof as possible supporting documents.

The office states that a correction may result in a property-tax refund if the taxpayer overpaid and the claim is approved. Any resulting refund is handled through the County Treasurer.

The Assessor currently accepts electronic Notices of Claim only through its designated claim process or designated inbox described by the office. Property owners using other online contact methods should not assume that a general inquiry substitutes for the formal Notice of Claim requirement.

Residential Legal Class Changes

A residential legal-class change is intended for property that has recently become the owner's primary residence. The Assessor's 2026 instructions distinguish the applicable tax years according to when the change occurred.

If the property became a primary residence between January 1 and July 1, 2026, the owner may request classification changes for both 2026 and 2027. If the property became the primary residence after July 1, 2026, the request can apply only to 2027 under the information provided by the Assessor.

Primary Residence Documentation

Supporting documents must show a matching occupant name and property address. The Assessor identifies the following documentation options:

A driver's license showing the occupant's name and property address.

A voter registration card showing the occupant's name and property address.

The name-and-address portion of the most recent federal or state tax return, accompanied by either a motor vehicle registration or utility bill showing the same occupant name and property address.

Owners should not send an entire tax return when using the tax-return option. The Assessor specifically requests only the portion showing the name and address, along with the required secondary documentation.

The residential property section also covers rental registration, mailing-address requests, physical property address notifications, residential forms, and annual valuation dates.

Mailing and Property Addresses

Mailing-address changes and physical property address issues are separate matters. For a mailing-address update, the Assessor requests the parcel number or property address. For a physical property address notification, the parcel number should be included, and the Assessor verifies physical address notifications with the city or town where the property is located.

The Assessor's forms library includes a Real Property Update Mailing Address form along with forms for appeals, residential legal-class changes, rental registration, mobile homes, valuation relief, business property, and other Assessor programs. Using the form that matches the exact service can help avoid routing a request through a general inquiry when a dedicated filing process exists.

Rental Property Registration

The Assessor provides residential rental property registration services and related forms. The residential property section directs owners to the appropriate forms for registering rental property and provides an online portal for rental-registration inquiries.

Owners should distinguish rental registration from legal-classification correction. Registering a residential rental property and asking the Assessor to correct a property that is wrongly classified as a rental involve different circumstances. Likewise, removing an existing rental registration is handled through an Assessor request rather than simply leaving the record unchanged.

The Assessor's FAQ and forms materials also address checking rental registrations, keeping registration information current, reporting unregistered rental property, and identifying qualified-family-member issues that can affect property classification.

Personal Exemption Programs

The Valuation Relief Programs Division administers personal exemption programs for qualifying property owners. The personal exemptions page contains the current application requirements and documentation for widowed applicants, totally disabled applicants, disabled veterans, certain surviving spouses, and other valuation-relief situations.

For the current program information shown for 2026, applications are due by February 28, or by September 1 when accompanied by an approved Exemption Deadline Waiver. The page states that applicants under the current rules must satisfy applicable income and residency qualifications.

For households with no children under age 18 residing in the home, the stated income limit is $39,865. For households with medically or physically disabled children, or children under age 18 who lived in the home during the previous calendar year, the stated limit is $47,826. Social Security benefits, military pensions, and veterans' disability payments are excluded from the income calculation described by the Assessor.

Common Application Documents

The exact documentation depends on the exemption category. The Assessor identifies combinations that may include:

A Personal Exemption Application.

Proof of Arizona residency or proof of primary residency, depending on the program.

Income documentation when required.

A spouse's death certificate for applicable surviving-spouse or widowed programs.

A Veterans Affairs letter showing the disability percentage for veteran disability programs.

An Arizona Department of Revenue Certificate of Disability for the applicable totally disabled exemption.

An Exemption Deadline Waiver for applications submitted during the waiver period.

The Assessor also states that an individual cannot receive more than one personal exemption program under multiple exemption categories covered by the cited statute.

Veteran Changes for 2027

The Assessor announced that several changes to disabled veterans' personal exemptions take effect beginning in January 2027 for Tax Year 2027. Those changes are separate from the 2026 program requirements described on the current valuation-relief page.

Under the announced 2027 changes, income limits for the disabled veteran and surviving-spouse property-tax exemption program are eliminated. Veterans rated 100 percent disabled by the U.S. Department of Veterans Affairs, including veterans receiving Total Disability Based on Individual Unemployability, may qualify for a full property-tax exemption on their primary residence.

The announced changes also expand eligibility for certain surviving spouses and allow qualifying veterans with a 100 percent disability rating, including TDIU, and qualifying surviving spouses to transfer the exemption to a new primary residence when they apply within 60 days of moving.

Because the 2027 legislation changes requirements that differ from the 2026 program information, applicants should use the requirements that apply to the tax year for which they are seeking the exemption rather than assuming the same standards apply to both years.

Business Personal Property

The Assessor also values taxable business personal property. The Business Personal Property section explains that this category may include assets such as desks, tables, computers, machinery, and equipment.

Business owners are responsible for reporting the acquisition costs of active assets used in the operation of the business each year. After receiving the report, the Business Personal Property Unit applies depreciation factors to the reported costs to determine Full Cash Value.

For the 2026 tax year, the Assessor mailed Arizona Business & Agricultural Business Property Statements on January 9, 2026, and the filing deadline was April 1, 2026. The 2026 Notice of Valuation for Personal Property was mailed August 14, 2026, and the stated appeal deadline is September 14, 2026.

The Assessor's electronic filing system accepts Excel and CSV files and has a 20 MB file-size limit. Business owners working with an existing account should use the account information associated with that business property rather than a residential parcel number unless the Assessor's filing specifically calls for it.

Mobile Home Records

The Mobile Homes section covers unsecured manufactured and mobile homes. The Assessor's Mobile Home unit identifies new owners, updates ownership when title transfers occur, and maintains assessment information for these personal-property accounts.

The Arizona Motor Vehicle Division is the Assessor's source for manufactured and mobile-home ownership, and titles must be registered with the Motor Vehicle Division. When an unsecured manufactured or mobile home is moved from one location to another, a 504 Property Tax Clearance is required under the statute cited by the Assessor.

An Affidavit of Affixture changes a manufactured or mobile home's status from personal property to real property. The affidavit must be filed in the county where the home is located.

For unaffixed mobile homes, the Assessor's 2026 calendar states that Notices of Valuation were mailed June 12, 2026 and that the deadline to file a Personal Property Petition for Review of Valuation was July 13, 2026.

Questions and Virtual Appointments

When a property issue does not fit a specific filing form, the Assessor provides an online inquiry and virtual appointment system. The form asks for the user's first and last name, email address, phone number, category, topic, property type, parcel or account number when applicable, and a description of the question.

Supporting documents may also be attached. The listed accepted formats include TIF, DWG, WLD, DXF, DGN, SHP, SHX, DBF, PRJ, SBN, SBX, ZIP, DOC, DOCX, TXT, XLSX, XLS, CSV, and PDF.

The Assessor states that requests submitted through the inquiry system are delivered to its Public Assistance Department and that higher-than-normal request volume may cause processing delays. Users can also schedule a virtual appointment with a Public Assistance clerk.

Issues Requiring Specific Procedures

A general inquiry should not be treated as a substitute for a formal filing when the Assessor has established a specific procedure. For example, valuation appeals have filing requirements and deadlines, Notices of Claim require evidence and a designated submission method, legal-class changes require specified documentation, and business or mobile-home appeals follow personal-property procedures.

Before sending a request, identify whether the issue concerns a search, record correction, classification, valuation appeal, claim, exemption, rental registration, business asset account, or mobile home. Matching the problem to the correct Assessor process reduces the risk of submitting information that cannot be acted on through the selected channel.

Assessor Office Contact

Maricopa County Assessor's Office
301 W Jefferson Street
Phoenix, AZ 85003
602-506-3406

Assessor FAQs

Can I respond to a property correction notice electronically?

Yes, electronic communication is now available for certain property error-correction procedures. Under legislation announced by the Assessor in April 2026, property owners who choose electronic communication may respond digitally to a Notice of Proposed Correction. The law also allows a Notice of Claim to be filed electronically and requires an electronic acknowledgment of receipt when that method is used. The change does not eliminate existing filing deadlines or other procedural requirements, and documents that legally must be served by certified mail will continue to follow that process. Property owners dealing with a correction notice should follow the instructions on that notice and use the Assessor's designated electronic process rather than treating an ordinary message as a formal response.

Where can I find older Assessor reports?

The Assessor maintains an official property reports archive with report sections for multiple years. The current archive lists years from 2019 through 2027 and also provides a Conservation Easement Report. This can be useful when researching historical Assessor information or comparing published county property data across different reporting years.

Can I receive Assessor notices electronically?

The residential property section provides an option to sign up for eNotices. Property owners interested in electronic notices should use the enrollment option available through the official residential property page. Because different Assessor filings and notices can carry statutory requirements, receiving information electronically should not be treated as permission to disregard the instructions, dates, or delivery requirements stated on an official notice.

How can I narrow down an unusual property-record issue?

The Assessor's official FAQ database can be filtered by subjects such as ownership, corrections, splits, property values, legal class, rental registration, data, common areas, historic tax treatment, and valuation notices. Using the category closest to the problem can help distinguish a routine record question from an issue that requires a specific Assessor procedure or form.