Evidence & Sources

Every factual claim on AssessCheck is traceable to a source we can name, with the date we verified it. This page explains what that means in practice: what evidence is in property-tax research, why traceability matters, what this site relies on, and — just as important — what it cannot establish and when only official documentation will do.

What is evidence in property-tax research?

Evidence is information you can point to: the statute that sets a deadline, the notice that shows your assessed value, the recorded sale that supports an opinion of value, the assessor’s own page that describes the appeal process. In property-tax work the distinction between a claim and evidence is practical, not academic — a review board weighs what you can document, and a homeowner comparing two websites needs to know which one cites the rule and which one is guessing.

Why evidence matters

• Property-tax rules are jurisdictional. A percentage that is a cap in one state is a ratio in another and nothing at all in a third. Traceable sources are the only way to tell which rule actually applies to you.
• Figures change. Rates are adopted annually, exemption amounts move with legislation, and CPI-linked limits are recalculated. A claim without a verification date cannot be trusted past the moment it was written.
• Decisions with real money ride on this: whether to file a protest, which deadline governs, what figure to enter on a form. Those decisions deserve better than a number of unknown origin.

What AssessCheck relies on

Three layers, in priority order:

1. Primary official sources. Statute text on official portals (Texas, Virginia, California, Arizona), administrative rules, state departments of revenue and taxation, county assessors, appraisers, treasurers and appeal boards. Every source we register is read — not assumed — and the registry records what was read and when.
2. Official materials we could not read in full. Some government sites block automated access. Where that happened, we say so in the source record and cite only what the source’s own official text (for example a search-result description) states.
3. Our own calculations. The property value estimator and the assessment checker apply verified rules to figures you supply. The rules are sourced; the inputs are yours; the output is arithmetic, not data.

When this information can be useful

• Understanding the notice you received — what each value on it means and which one the law attaches limits to.
• Deciding whether your assessment warrants a closer look, and what evidence would support your case if it does.
• Estimating how your state’s system turns a value into a tax bill, before the bill arrives.
• Finding the official office, form and deadline that governs your situation, in your state.

When official documentation is essential

Some questions only the responsible authority can answer. Rely on your county assessor, property appraiser, tax collector, board of equalization or equivalent office — not this site — for:

• Your property’s current official value and its history.
• The deadline that governs your parcel this year — many deadlines anchor to the date your specific notice was mailed or delivered.
• Which exemptions apply to you and their exact amounts, which vary by county and by your circumstances.
• The tax rate actually applied to your parcel, including special assessments and fees.
• Procedural requirements for filing, evidence exchange and hearings.

What AssessCheck can verify

• The rules of each covered state: assessment ratios, cap mechanics, exemption structures, notice requirements and appeal ladders, each cited to the official source it was verified from.
• The arithmetic that connects those rules — what the property value estimator and assessment checker compute, shown step by step.
• Which sources say what, so you can read the primary document yourself instead of trusting a summary — ours included.

What AssessCheck cannot determine

• Your property’s correct value. No tool on this site values property; the estimator works from a figure you supply.
• Whether your assessment is wrong, or whether a protest, petition or appeal will succeed.
• Your actual tax bill, which depends on local rates, exemptions and special assessments that only your tax office can state.
• Legal, tax, appraisal or financial advice. This is an informational tool, and it is not affiliated with any government agency.

Our sources

The registry behind every page holds, for each source: the publisher, the exact URL, the date we verified it, what it supports, and notes recording what was read. The state-by-state official sources are listed on our resources page. How we select, verify and retire sources is described in our methodology.

How we use sources

• Claim-level citation. Pages that make factual claims render a Sources block; each cited source names the specific claim it supports.
• Verification dates, honestly. Sources record the date they were actually read. Where a page could not be read, the record says so rather than implying otherwise.
• No substitution. When a figure cannot be verified — a county rate, an exemption amount, a year’s inflation multiplier — the pages say the figure is not available rather than publishing a placeholder. Where a whole tool would require unverified data, the tool is not built for that state.
• Contrast, not contamination. Each state’s pages are written against that state’s own vocabulary and statutes, and automated tests keep one state’s law from drifting into another’s pages.

Evidence for a protest or appeal

If you are preparing a protest, petition or appeal, the practical evidence guides cover what each kind of evidence — photographs, repair estimates, sales documentation, comparables, surveys — can and cannot show, starting with the property tax protest evidence guide and the state-specific evidence pages linked from each state.

Important disclaimer

AssessCheck is an informational tool. It does not replace an official assessment, appraisal, tax bill, legal advice or professional valuation, and it is not affiliated with any appraisal district, property appraiser, or government agency. Verify current deadlines, values and procedures with the authority that governs your property. Read the full disclaimer.