Assessor

The Los Angeles County Assessor maintains property assessment records, determines taxable values, reviews ownership changes and new construction, administers qualifying exemptions, and provides property information to owners and the public. This article explains how to search Assessor records, identify the correct office, prepare an inquiry, request record corrections, review an assessed value, and avoid confusing Assessor services with property tax billing or formal assessment appeals.

Assessor Duties and Services

The Assessor’s Office is responsible for identifying taxable property in Los Angeles County and placing assessed values on that property. Its work covers residential real estate, commercial and industrial property, business personal property, vessels, aircraft, manufactured homes, apartments, and other specialized property categories.

For real property, the Assessor maintains information about land and improvements. Improvements include assessable buildings and structures on the land. The term does not necessarily mean that the owner recently remodeled or upgraded the property.

The Assessor also receives recorded deeds and building permit information. These records help the office determine when a change in ownership or assessable new construction requires a new appraisal. In addition, the office processes exemption claims, property data correction requests, mailing address changes, decline-in-value applications, and certain disaster-related claims.

Assessor Versus Tax Collector

The Assessor determines assessed values and maintains assessment records. The Assessor does not perform the same function as the Treasurer and Tax Collector, which handles property tax bills and payments. A question about the description, ownership record, exemption, land value, improvement value, or reassessment generally belongs with the Assessor. A question about an amount due, payment status, delinquency, or tax bill payment generally belongs with the tax collection system.

An assessed value is also different from the amount of tax owed. Tax bills may include bonded indebtedness and direct assessments in addition to the general property tax levy. Contacting the correct department first can prevent delays and duplicate inquiries.

Property Search and AIN Records

The official Los Angeles County Assessor property search provides access to property and assessment information. A property owner, buyer, researcher, or other user should begin with the most accurate identifying information available.

The Assessor Identification Number, commonly called the AIN or parcel number, is one of the most useful identifiers for Assessor transactions. An address may change in format or may not match the format used in county records, while the AIN identifies the assessed parcel.

Information to Prepare

Before searching or contacting the office, gather the details that directly identify the property and the issue. Depending on the request, useful information may include:

The complete property address, including unit information when applicable.
The Assessor Identification Number.
The property owner’s name as it appears on available records.
The tax year or assessment year involved.
The date of a transfer, construction completion, or notice.
A copy of the Notice of Assessed Value Change or other relevant document.
A clear explanation of the record, value, exemption, or ownership question.

Users should review numbers carefully before submitting a form or inquiry. An incorrect AIN can direct staff to a different parcel, and an incomplete address can make it difficult to identify condominium units, apartment interests, or properties with similar street numbers.

Limits on Online Ownership Details

The Assessor maintains many records for assessment purposes, but California law prohibits publishing identifying information such as a homeowner’s name online without the owner’s written permission. The absence of an owner’s name from an online property result does not mean that the Assessor lacks an ownership record.

Property ownership information may need to be requested through the County Registrar-Recorder/County Clerk. Assessment information, property characteristics, maps, transfer lists, and other Assessor records follow separate public-record procedures.

How Assessed Values Work

Property taxes are based in part on the assessed value assigned to land and improvements. The Assessor’s real property assessment overview explains the relationship among assessed values, ownership changes, new construction, and supplemental assessments.

Under Proposition 13, the maximum general property tax levy cannot exceed 1% of a property’s assessed value, plus bonded indebtedness and direct assessment taxes. Annual increases in assessed value are generally limited to 2%, except when a change in ownership or new construction creates a new assessment event.

A property is generally reassessed to current market value when ownership changes or new construction is completed. This new value becomes a base year value for the reassessed interest or newly constructed portion. The rest of a property may continue under an existing assessed value when only part of the property is affected.

Supplemental Assessments

State law requires supplemental assessments after qualifying changes in ownership or completion of new construction. A supplemental assessment reflects the difference between the previous value and the newly determined value.

The Auditor-Controller calculates the supplemental property tax and prorates it based on the number of months remaining in the fiscal year. The county fiscal year runs from July 1 through June 30.

A change in ownership or completion of new construction between January 1 and May 31 can result in two supplemental assessments and two supplemental tax bills. One applies to the remainder of the fiscal year in which the event occurred, and the other applies to the following fiscal year.

The Assessor mails a Notice of Assessed Value Change before supplemental tax bills are issued. Supplemental bills are separate from regular annual property tax bills. They are sent directly to the property owner rather than to an impound account that may be maintained by a lender.

Ownership Changes and Reappraisal

Recorded transfers are reviewed to determine whether a property or ownership interest must be reappraised. The Assessor generally receives a copy of a recorded deed and evaluates the transaction under California property tax law.

The date of reappraisal is generally the deed recording date. For property acquired through an estate or living trust after an owner’s death, the reappraisal date is the date of death rather than the date the property is distributed to a beneficiary.

The Assessor’s change in ownership information explains that the Ownership Division reviews recorded deeds and may also identify ownership changes through owner reporting, State Board of Equalization information, trade publications, and public filings.

Transfers That May Be Excluded

Some transfers may qualify for an exclusion from reassessment, but the applicable requirements depend on the type and date of the transfer. Transfers between spouses and registered domestic partners do not cause a reappraisal for property tax purposes. This includes qualifying transfers resulting from death, divorce, or termination of a domestic partnership.

The addition of joint tenants does not generally result in an immediate reappraisal. Transfers involving irrevocable trusts are reappraisable in most cases, although exclusions may be available in qualifying circumstances.

Property owners should not assume that a family transfer, trust transaction, or ownership restructuring is automatically excluded. Some exclusions require a claim form and supporting documentation. Missing a required claim can affect how the transfer is processed.

Proposition 19 Requirements

Proposition 19 changed property tax benefits for certain inherited residences, homeowners over age 55, severely disabled homeowners, and victims of wildfires or other natural disasters.

For qualifying parent-child or grandparent-grandchild transfers occurring on or after February 16, 2021, the transferred property must have been the transferor’s principal residence. The child or grandchild must make it a principal residence within one year and file a qualifying Homeowners’ Exemption or Disabled Veterans’ Exemption within one year of the transfer.

For qualifying base year value transfers by homeowners over age 55 or severely disabled homeowners, both the original and replacement properties must meet principal-residence requirements. The claimant must own and occupy the original property at the time of sale or within two years of purchasing or constructing the replacement residence. Proposition 19 allows qualifying replacement residences anywhere in California and permits eligible homeowners to use the transfer benefit up to three times.

New Construction and Remodeling

The Assessor receives building permit information from local permitting jurisdictions and reviews each project to determine whether the work is assessable. A permit does not by itself establish the final assessment result. The type, scope, and effect of the work must be evaluated.

The official new construction and remodeling guidance describes assessable additions, renovations, changes in use, and work that may be treated as normal maintenance or repair.

Common Assessable Projects

New construction can include a substantial addition to land or improvements, an alteration that brings an improvement to a like-new condition, work that extends a property’s economic life, or a project that changes the way the property is used.

Examples of work that may be assessable include:

Adding a new floor or subterranean level.
Building a room addition or increasing living space.
Converting an unfinished attic or basement into living space.
Adding a bathroom, garage, or elevator.
Constructing an accessory dwelling unit or junior accessory dwelling unit.
Changing a property from industrial or retail use to residential use.
Completing a major renovation that leaves the property substantially equivalent to new.

The value of qualifying new construction is added to the existing improvement value. The existing land and unaffected improvements do not necessarily receive a full reassessment solely because new construction occurred.

Maintenance and Cosmetic Work

Normal maintenance and repair are generally not assessable. Examples include termite repairs, dry rot repairs, reroofing, and replacing doors, windows, fences, or decks. Replacing kitchen or bathroom cabinets, countertops, flooring, fixtures, or built-in appliances with items of similar quality may also be treated as nonassessable maintenance.

More extensive remodeling may be assessable when it changes the floor plan, upgrades plumbing or electrical capacity, increases the size of a room, changes property use, raises the quality class, or extends the useful life of the property. Each permit and project is reviewed individually, so two projects with similar labels may receive different treatment based on their actual scope.

Exemptions and Relief Claims

The Assessor administers several property tax exemption and exclusion programs. The correct form depends on the property, the owner, the use of the property, and the event that created the claim.

The official Assessor forms directory includes forms for homeowners, disabled veterans, nonprofit organizations, ownership changes, new construction exclusions, disaster damage, business property, vessels, aircraft, base year value transfers, and property record corrections.

Homeowners’ Exemption

A homeowner may qualify for a $7,000 reduction in assessed value when the home is owned and used as the principal residence on January 1. New property owners automatically receive a Homeowners’ Property Tax Exemption Claim Form.

The exemption may also apply to a supplemental assessment when the prior owner did not claim it. The claim can be mailed or submitted through the available online filing process, subject to the form instructions and any required supporting documentation.

The Homeowners’ Exemption is different from homestead protection. The exemption reduces taxable assessed value for a qualifying principal residence. Homestead protection concerns home equity and creditors and does not determine the property’s assessed value.

Disaster and Calamity Claims

Owners whose homes or businesses were damaged or destroyed by a natural disaster may qualify for property tax relief. The forms directory includes the Application for Reassessment of Property Damaged or Destroyed by Misfortune or Calamity, identified as form ADS-820.

Property owners who have already filed a misfortune or calamity claim can use their AIN or property address to check the claim status through the Assessor’s system.

Property Data Corrections

An owner who believes the Assessor’s official record contains an incorrect building or land detail may submit a Property Data Change Request, form ASSR-129. The request should identify the specific record being challenged and provide information that supports the correction.

A data change request concerns the factual property record. It is not the same as a decline-in-value application, an exemption claim, or an appeal of an assessed value. Selecting the correct process helps the office route the submission to the appropriate unit.

Decline-in-Value Reviews

A decline-in-value review addresses a situation in which a property’s current market value is lower than its assessed value as of January 1 for the year under review. Proposition 8 permits a temporary reduction when the market value falls below the trended Proposition 13 base year value.

For the 2026-2027 tax year, the Assessor began accepting decline-in-value applications on July 2, 2026. The filing deadline is November 30, 2026.

The Assessor’s assessed value review and appeal information distinguishes an informal Assessor review from a formal appeal filed with the Assessment Appeals Board.

Informal Review Versus Appeal

A property owner may ask the Assessor to review and explain a value. However, an informal review does not replace a formal Assessment Appeals Board filing and does not extend the appeal deadline.

For a supplemental assessment, adjusted supplemental assessment, adjusted property tax bill, or escaped assessment, a formal appeal generally must be filed within 60 days of the applicable mailing date or postmark date described in the notice or bill.

For the regular assessment roll, the formal appeal filing period runs from July 2 through November 30. When November 30 falls on a Saturday, Sunday, or legal holiday, a filing or postmark on the next business day is treated as timely.

The Assessment Appeals Board acts as an impartial third party in disputes between a property owner and the Assessor. Filing an appeal does not mean the Assessor made an error, and requesting an Assessor review does not preserve formal appeal rights.

Business Property Assessments

The Assessor assesses unsecured property owned by businesses in Los Angeles County and conducts business audits required by the state. Business personal property can include machinery, equipment, fixtures, supplies, and leasehold improvements used in a trade or business.

Unlike real property, business personal property is generally reassessed annually because a business may acquire or dispose of assets during the year. The business property assessment information explains annual statement requirements and the types of property businesses must report.

Businesses with personal property and fixtures costing $100,000 or more must file a Business Property Statement each year by April 1. The statement reports acquisition costs for supplies, equipment, fixtures, and improvements at each business location in the county.

Businesses with personal property and fixtures below the $100,000 threshold are generally not required to file annually. Their value may be established through an initial statement or an on-site appraisal and may later be adjusted through subsequent appraisals. Business inventory is exempt from property taxation.

Public Records and Record Requests

The Assessor maintains assessment rolls, assessment maps, lists of properties transferred during the preceding two years, organizational exemption claims, supporting documents, market data, and information about property characteristics.

The Assessor public records request process allows the public to request and inspect reasonably identifiable records under the California Public Records Act and county policies.

A request should describe the desired records precisely. Broad wording can make it difficult to determine which documents are being requested. Include the property address, AIN, date range, document type, or assessment year when those details apply.

The Assessor’s policy is not to charge for duplicating routine records. Requests involving media inquiries, intergovernmental matters, or formal Public Records Act or Freedom of Information Act matters may be handled through the Public Information Officer.

Choosing the Correct Office

The Assessor operates headquarters, district offices, regional offices, a courthouse office, and a temporary satellite site. Property-specific valuation questions may be handled by the district assigned to the property. Ownership, exemptions, mapping, specialized property, and public-service matters may be directed to specialized units or appointments.

The official district office locator helps users identify the office assigned to a property. This is useful when an inquiry concerns residential or commercial valuation within a particular district.

North District Service Changes

The Sylmar office closed effective March 26, 2026. North District Public Services and Operations temporarily moved to the Assessor’s headquarters in downtown Los Angeles. The North District mailing location is also at the Hall of Administration in a separate room from the temporary public-service counter.

North District property owners may also visit the temporary Castaic Library Satellite Site until new North District office locations become operational. The satellite site is open on Mondays and Fridays from 10:00 a.m. to 5:00 p.m., except county holidays. Visitors must be in line by 4:45 p.m.

Office Hours and Access

Headquarters and the East, South, West, and Lancaster offices are generally open Monday through Friday from 8:00 a.m. to 5:00 p.m., except county holidays. Headquarters requires visitors to be in line by 4:45 p.m.

The Beverly Hills Courthouse Office is open Tuesday through Thursday from 8:00 a.m. to 4:00 p.m., except county and Superior Court holidays. Visitors must be in line by 3:45 p.m.

Because operating locations and schedules can change, users planning an in-person visit should review the official Assessor office locations and hours before traveling.

Appointments and Online Inquiries

The Assessor accepts general inquiries and offers appointments for several service categories. An inquiry that is not tied to a specific property address may be submitted with the requester’s name, email address, phone number, explanation, and an optional PDF or DOCX attachment. The stated response time for the contact form is one to three business days.

The Assessor appointment system offers Microsoft Teams and in-person appointments. Available appointment categories include:

Property ownership, transfers, and Proposition inquiries.
Residential and commercial-industrial valuation questions.
Homeowners’ Exemption matters.
Disabled Veterans’ Exemption matters.
Major exemptions for qualifying nonprofit and public uses.
Mapping and geographic information system services.
Data sales and public information inquiries.
High-value or complex commercial and multi-residential property.
Marine property, aircraft, airlines, and manufactured homes.
Special business property, leasing, vending, and apartment furnishings.

Preparing a Clear Submission

A concise, property-specific explanation usually produces a more useful response than a general request for help. State the result being questioned, identify the relevant notice or form, and explain the correction or clarification being requested.

When attaching a document, confirm that it relates to the same property and tax year identified in the message. Avoid sending unnecessary personal or financial records when the Assessor’s form does not request them.

Common Assessor Mistakes

Contacting the Wrong Department

Sending a payment question to the Assessor or an assessed-value question to the tax collection office can delay the response. Identify whether the issue concerns property data, assessed value, ownership, exemption eligibility, a tax bill, or a payment before selecting a department.

Missing Appeal Deadlines

An Assessor review does not preserve the right to a formal appeal. Property owners who want to protect formal appeal rights must file with the Assessment Appeals Board within the applicable filing period, even when an informal review is pending.

Using the Wrong Form

A property data correction, mailing address change, decline-in-value request, ownership exclusion, disaster claim, and exemption application each use a different process. Read the form title and filing instructions before submission.

Assuming All Remodeling Is Taxable

Routine maintenance, repair, and replacement with materials of similar quality are generally treated differently from additions, major rehabilitation, capacity upgrades, and changes in use. The Assessor reviews the actual project rather than relying only on a permit description.

Ignoring Supplemental Bills

Supplemental tax bills are separate from regular annual bills and are sent directly to the property owner. Owners should not assume that a lender’s impound account will receive or pay a supplemental bill.

Relying Only on an Address

An address alone may be insufficient when a property has multiple units, several parcels, or a recently changed address format. Include the AIN whenever it is available.

Assessor Offices

Los Angeles County Assessor Headquarters
Kenneth Hahn Hall of Administration
500 W. Temple Street, Room 225
Los Angeles, CA 90012-2770
(213) 974-3211
(888) 807-2111

North District Office Temporary Public Services
Kenneth Hahn Hall of Administration
500 W. Temple Street, Room 225
Los Angeles, CA 90012-2770
(818) 833-6000

North District Office Mailing Address
Kenneth Hahn Hall of Administration
500 W. Temple Street, Room 293
Los Angeles, CA 90012-2770
(818) 833-6000

North District Castaic Library Satellite Site
27971 Sloan Canyon Road
Castaic, CA 91384
(818) 833-6000

East District Office
1190 Durfee Avenue
South El Monte, CA 91733
(626) 258-6001

South District Office
1401 E. Willow Street
Signal Hill, CA 90755
(562) 256-1701

West Regional Office
6167 Bristol Parkway, Suite 100
Culver City, CA 90230
(310) 665-5300

Beverly Hills Courthouse Office
9355 Burton Way, Suite 400
Beverly Hills, CA 90210
(310) 665-5300

Lancaster Regional Office
251 E. Avenue K-6
Lancaster, CA 93535
(661) 940-6700

Assessment Appeals Board
Kenneth Hahn Hall of Administration, Room B-4
500 W. Temple Street
Los Angeles, CA 90012-2770
(213) 974-1471

Assessor FAQs

How does the Homeowner Alert Service help property owners?

The Homeowner Alert Service is an email-based notification program designed to alert registered property owners to potential fraud-related activity involving their property records. Registration can provide an early warning that allows an owner to review unexpected activity and determine whether further action is necessary. The service does not replace recorded documents, assessment notices, or other official county communications. Property owners should register through the Los Angeles County Assessor website and keep their email information current so alerts are not missed.

Can the Spanish Homeowners’ Exemption form be filed online?

The Assessor’s e-file system does not currently accept the Spanish-language Homeowners’ Exemption application online. A property owner who wants to complete the application in Spanish must download the Spanish version and submit it by mail according to the form instructions. Applicants should review the form carefully because supporting documents may be required. The English-language application may be available for online submission. Current filing options are explained on the official Homeowners’ Exemption page.

What proof is needed for an accessibility construction exclusion?

Construction that makes a principal residence more accessible for a person with a disability may qualify for exclusion from assessment. Filing the claim alone may not be sufficient. The owner must provide proof of disability and a statement identifying the construction, installation, or modification that was necessary to improve accessibility. The explanation should connect each improvement directly to the accessibility need rather than describing the project only as general remodeling. Required claims and instructions can be found in the Assessor’s official property forms directory.

Are all Assessor forms available for e-filing?

No. The forms directory includes a mix of downloadable forms and forms that can also be submitted online. An “E-File” or “Submit Online” option appears only when electronic filing is available for that specific document. Property owners should not assume that a downloaded form can be emailed or uploaded through another filing page. Follow the submission method listed beside the exact form number, and use the current version rather than a saved copy from an earlier year.