Glossary of Terms

Property Taxation Terms*

Ad Valorem Property Tax Taxes imposed on the basis of the property's value.
Assessed Value (AV) The taxable value of a property against which the tax rate is applied.
Assessment Appeal Due process initiated by taxpayer if the assessed value of their property cannot be agreed upon with the Assessor.
Assessment Appeals Board (AAB) Differences over the valuation of property are handled by the local Board of Equalization. This board is composed of the five members of the Board of Supervisors. They consider all evidence presented by the property owners and the Assessor's Office at a formal public hearing. 
Assessment Roll The official list of all property within the County assessed by the Assessor.
Base Year Value (BYV) The fair market value of a property at the time of the 1975 lien date, or the date of the subsequent new construction or change in ownership.
Business Personal Property Property which is movable and not affixed to the land, and which is owned and used to operate a business, such as machinery, equipment, computers, furniture, and supplies.
Change In Ownership A transfer of real property resulting in the transfer of the present interest and beneficial use of the property.
California Consumer Price Index (CCPI) Determined annually by the California Bureau of Labor Statistics.
Escape Assessments Assessments levied outside the normal assessment period for the lien date(s) in question.
Exclusions Qualifying transfers of real property which are excluded from reappraisal if a timely claim is filed with the Assessor's Office.
Exemptions Legally qualified deductions from the taxable assessed value of the property.
Factored Base Year Value (FBYV) A property's base value, adjusted annually by the change in the CCPI, not to exceed 2 percent. It is the upper limit of taxable value each year.
Fiscal Year The period beginning July 1 and ending June 30.
Fixture Tangible property securely affixed to real property.
Full Cash Value (FCV) The amount of cash or its equivalent value that property would bring if exposed for sale in the open market, and as further defined in Revenue and Taxation Code Section 110.
Improvements Buildings or structures generally attached to the land.
Lien The amount owed and created by the assessment of the property, or the amount levied against property by a taxing agency or revenue district.
Lien Date The date when taxes for any fiscal year become a lien on property. The Lein Date for California property is 12:01 a.m., January 1.
New Construction The construction of new buildings, additions to existing buildings, or alterations which convert the property to another use or extends the economic life of the improvement.
Personal Property Any property except real estate, including airplanes, boats, and business property.
Possessory Interest (PI) Interest of a lessee in government-owned property. Examples of a PI include the exclusive right to use public property, such as Special Use Permits issued by the US Forest Service for outdoor guides, private trail or race events, and summer home tract cabins.
Proposition 13 (Prop 13) Passed by California voters in June 1978, Proposition 13 is a Constitutional amendment that limits the taxation of property and creates a procedure for establishing the current taxable value of locally assessed real property, referencing a base year full cash value.  
Proposition 8 (Prop 8) Passed by California voters in November 1978, Proposition 8 requires the temporary reduction in the assessed value when there is a decline in market value below the property's factored base year value.
Proposition 19 (Prop 19) Passed by California voters in November 2020, Proposition 19 generally expands the ability to transfer assessed value and narrows property tax benefits for intergenerational transfers. New transfer provisions were added for victims of disasters and the severely handicapped.
Real Property Land that has been legally defined and improvements that have been made to the land.
Secured Roll Assessment roll on which the taxes are secured by a lien against the real estate.
Special Assessments Direct charges or flat fees against property which are included in the total tax bill but are not based upon the Assessor's valuation of the property. Examples are solid waste charges or water infrastructure fees. 
State Board of Equalization (BOE) The Board consists of four members elected by California voters by district, and the State Controller. Their duties include administering various State taxes and fees, and serving as an appellate body for property, business, and income tax assessments. Through guidelines and rules, the Board promotes uniformity in local assessment practices.
Supplemental Assessment Upon a change in ownership or completion of new construction, a supplemental assessment is issued in addition to the annual regular assessment and is based on the net difference between the previous assessed values and the new value for the remainder of the assessment year(s).
Tax Rate The ratio of the tax to the tax base. The minimum ad valorem property tax rate is 1% of the net taxable value of the property. The total tax rate may be higher due to voter-approved general obligation bonds that are secured by property taxes for the annual payment of principal and interest.
Tax Roll The official list of property subject to property tax, together with the amount of assessed value and the amount of taxes due, as applied and extended by the Auditor.
Tax Rate Area (TRA) A geographic area having the same property tax allocation factors.
Transfer of Ownership Change in ownership or change in manner in which property is held.
Unsecured Roll Assessment roll consisting largely of business personal property on which the property taxes are not secured by a lien against the real estate.
*Explanation of terms are provided to simplify assessment terminology, but do not replace legal definitions.