Property tax glossary

Assessment Ratio

The percentage of a property’s market value that a state uses to calculate its taxable assessed value.

Comparable Sales (Comps)

Recent sales of similar nearby properties, used as evidence that your assessment is too high.

Overassessment

When a property’s assessed value exceeds its true market value, so the owner overpays tax.

Appeal Deadline

The last date to file a property tax appeal; miss it and you usually wait a full year.

Market Value

The price a property would likely sell for on the open market.

Assessed Value

The dollar value a tax assessor assigns to a property to calculate its taxes.

Millage Rate

The property tax rate, expressed as dollars of tax per $1,000 of assessed value.

Effective Tax Rate

The actual percentage of a home’s market value paid in property tax each year.

Homestead Exemption

A tax break that reduces the taxable value of your primary residence.

Property Tax Protest

The Texas term for formally challenging your property’s assessed value.

Informal Review

An optional first meeting with the assessor to resolve your appeal before a formal hearing.

TRIM Notice

Florida’s “Truth in Millage” notice, mailed each August, which opens the appeal window.

Reassessment

The periodic process where a county updates property values, often every 1–5 years.

Board of Equalization

A local body that hears property tax appeals and decides whether to adjust assessments.

Uncapping (Assessment Reset)

When a home sells and its capped taxable value resets to full market value, spiking taxes.

Escrow Shortage

When your mortgage escrow underfunds a risen tax bill, forcing a higher monthly payment.

Notice of Assessment

The official document telling you your property’s assessed value for the coming tax year.

Appeal Hearing

A short, informal meeting where you present evidence for a lower assessment.

Mass Appraisal

The statistical method assessors use to value thousands of properties at once — and a common source of errors.

Arm’s-Length Sale

A sale between unrelated parties acting in their own interest — the gold standard for a comparable.

Equalization

Adjusting assessed values across a jurisdiction so similar properties are taxed fairly and consistently.

Uniformity (Equity) Appeal

An appeal arguing your property is assessed higher than comparable properties, regardless of market value.

Appraisal District (CAD)

In Texas, the county body that appraises all property for tax purposes — where you file your protest.

Notice of Appraised Value

The annual notice stating your property’s appraised value — and the start of your protest window.

Appraisal Review Board (ARB)

The independent Texas panel that hears property tax protests when informal resolution fails.

Burden of Proof

Who must prove the value is wrong — and in several states it shifts to the assessor.

Fair Market Value

The price a property would sell for between a willing buyer and seller — the benchmark for every appeal.

Tax Levy

The total amount a taxing authority needs to raise — which, divided by total value, sets the rate.

Assessment Cap

A legal limit on how much a property’s taxable value can rise each year.

Ad Valorem Tax

A tax based on the assessed value of property — the legal term for property tax.

Special Assessment

A separate charge for a local improvement (sidewalks, sewers) that is not based on property value.

Senior / Over-65 Exemption

A reduction or freeze on property taxes available to older homeowners in many states.

Tax Abatement

A temporary reduction or elimination of property taxes, often to encourage development or improvements.

Grievance Day

The set date (mainly in New York) when homeowners can formally challenge their assessment.

Common Level Ratio (CLR)

A state-published ratio (notably Pennsylvania) that converts assessed value to current market value.

Highest and Best Use

The most profitable legal use of a property — which can push an assessment above its current use.

Cost Approach

A valuation method: land value plus the depreciated cost to rebuild the structure.

Sales Comparison Approach

Valuing a home by comparing it to recent sales of similar properties — the basis of most appeals.

Income Approach

Valuing a property from the rental income it produces — used for commercial and rental property.

Functional Obsolescence

A loss in value from outdated or poorly designed features — a valid reason to lower an assessment.

Economic (External) Obsolescence

A loss in value from outside factors like a nearby nuisance — usable evidence in an appeal.

Parcel Number (APN)

The unique ID your county uses to identify your property on every tax record and appeal.

Tax Assessor

The local official responsible for determining the value of property for tax purposes.

Tax Certiorari

A legal proceeding to challenge an assessment in court after administrative appeals are exhausted.

Save Our Homes (Florida)

Florida’s constitutional cap limiting annual assessment increases on homesteads to 3%.

Proposition 13 (California)

California’s law capping assessment increases at 2% a year and reassessing only on sale.

Rollback / No-New-Revenue Rate

The tax rate that would raise the same revenue as last year — a check on rising bills.

Evidence Packet

The organized set of comps, photos, and records you present to support a lower value.

Small Claims Assessment Review (SCAR)

A low-cost New York process for homeowners to appeal after Grievance Day.

Taxable Value

The value your tax is actually calculated on, after ratios, caps, and exemptions are applied.

Pay Under Protest

Paying a disputed tax bill on time while formally reserving your right to appeal and be refunded.

Assessment / Valuation Date

The single date each year on which your property’s value is legally fixed.

De Minimis Threshold

A minimum gap between assessed and market value some boards require before granting a reduction.

Personal Property Tax

A tax on movable business assets (or vehicles), separate from real-estate tax.

Circuit Breaker Relief

A program that caps property tax as a share of income for lower-income or older homeowners.

Property Tax Lien

A legal claim against your property for unpaid taxes — separate from any valuation dispute.

Council Tax Band

The A–H valuation band (England/Scotland) that sets how much Council Tax you pay.

Valuation Office Agency (VOA)

The UK government body that sets Council Tax bands and handles band challenges.

Stamp Duty Land Tax (SDLT)

The UK tax paid when buying property — often overpaid, and sometimes reclaimable.

Multiple Dwellings Relief (MDR)

An SDLT relief for buying more than one dwelling in a single transaction.

LBTT (Land and Buildings Transaction Tax)

Scotland’s tax on property purchases, collected by Revenue Scotland — the replacement for Stamp Duty.

LTT (Land Transaction Tax)

Wales’ tax on property purchases, collected by the Welsh Revenue Authority — the replacement for Stamp Duty.

Additional Dwelling Supplement (ADS)

Scotland’s higher-rate LBTT surcharge on additional properties — reclaimable if you sell your old home within 36 months.

Uninhabitable Property (SDLT/LBTT/LTT)

A property not suitable for use as a dwelling at purchase may be taxed at lower non-residential rates.

Mixed-Use Property (SDLT/LBTT/LTT)

A property with both residential and commercial elements, taxed at lower non-residential transaction-tax rates.