Data Sources

Every tax rate and fee on this site is researched from official government sources. This page explains which sources we use and how we rank them when they disagree.

Reviewed by William Smith. Last updated October 1, 2026.

Our source hierarchy

When we research a state, we look for the most authoritative source first and work down only if we must:

• State Department of Motor Vehicles (DMV) or equivalent motor vehicle agency
• State Department of Revenue or Taxation
• Other official state government agencies
• State statutes and legislative sources
• Official county government sources
• Official city government sources
• Official government forms and fee schedules
• Other authoritative sources only when official ones are unavailable

How we resolve conflicts

When two sources disagree, we do not simply pick the lower or higher number. We check:

• Which source is current, and the effective date of each figure.
• Whether the sources describe different transaction types (dealer vs private sale).
• Whether one figure is state-level and another is local.
• Whether one refers to a new vehicle and another to a used vehicle.
• Whether one is a base fee and another includes extra charges.

If real uncertainty remains after checking, we explain it on the page rather than present a false certainty. Our methodology page shows how a resolved figure then turns into the numbers you see on a state page.

Official sources by state

These are the agencies behind each state we’ve published. Each state page lists its own full source list.

Dates and freshness

Vehicle tax and DMV rules change often. We record when each figure was checked, preserve effective dates when an official source gives one, and update the page when the law changes. Confirmed changes appear on our rate and fee updates log, with the date and what changed.

Tell us about a source

If you represent a state or local agency, or you have found an official source that is more current than ours, email admin@taxtitleandlicensecalculator.com. We will review it and update the page if it checks out.