Editorial policy
Anyone can publish a number. These are the rules that decide whether a number gets published here, and what happens when one turns out to be wrong.
Maintained by Arthur Patch · Last updated
Who researches and publishes
CarFeeCalc is researched, built and maintained by Arthur Patch, one person rather than a content team. That is worth stating plainly because it explains the shape of the site: 10 states published carefully rather than fifty generated quickly. There is no editorial board to appeal to and no anonymous byline to hide behind — if something here is wrong, it reaches the person who can fix it.
The seven rules
1. Primary sources only
A figure may be published when it comes from the state motor vehicle agency or revenue department’s own fee schedule, its published PDF, or the statute itself. Aggregator sites, dealer blogs and other calculators are treated as leads to check, never as evidence. Where a secondary source contradicts what the primary source says, the primary source wins and the secondary source is ignored.
2. Every figure carries a date
Each state page lists the sources used and the date every figure on it was last confirmed against them. A page without a date is a page that cannot be audited, and an undated fee is indistinguishable from a stale one.
3. Unconfirmed means labelled, not omitted
Where a fee is real but its exact amount could not be confirmed against a primary source, the calculator marks it as an estimate in the interface rather than presenting it as fact. Quietly rounding an unknown into a total is the failure this rule exists to prevent.
4. Conflicting local rates are dropped
If two credible sources disagree on a city or county rate, that jurisdiction is removed from the calculator rather than guessed at. A missing city is an inconvenience; a wrong rate is a wrong tax bill.
5. Assumptions never cross state lines
Trade-in credit and rebate treatment are the most common source of error in vehicle fee tools, because they vary and look like they should not. Each state’s rule is established from that state’s own source, never inferred from a neighbour or from what is usual.
6. Published worked examples are reproduced
Where a state publishes its own example calculation, the engine is tested against it and that test stays in the regression suite permanently. There are currently 196 such checks, and they run before any change can be deployed.
7. Ask whether a tax applies at all
Not every tax that exists in a state applies to a vehicle. Illinois home rule sales taxes legally exclude titled property, which is why Chicago’s well-known 10.25% is not what you pay on a car — and why most calculators overstate it by hundreds of dollars.
Where the rules changed the answer
A policy is only worth reading if it costs something to follow. These are cases where the statute disagreed with the consensus, and the statute won:
- FloridaNo electric-vehicle registration surcharge exists. The widely republished “$200, rising to $250” came from a bill that never passed; the statute sets the EV licence tax equal to a petrol car.
- IllinoisThe $10,000 cap on the trade-in credit expired on 1 January 2022. Dealer sites and calculators still quote it as current.
- TexasSeparately stated manufacturer rebates are excluded from taxable consideration, so a rebate genuinely reduces the tax — rare enough that most tools assume the opposite.
- South CarolinaA trade-in does reduce the Infrastructure Maintenance Fee. The largest competitor in this category openly states it could not confirm this.
- CaliforniaA trade-in reduces nothing at all — the CDTFA’s own worked example counts the trade-in as part of the purchase price.
Corrections
Errors are treated as defects, not as embarrassments. If you find one, write to hello@carfeecalc.com with the page, the figure you believe is wrong, what it should be, and where that comes from — the agency's fee schedule, the published PDF, or the statute section.
Reports that cite a source are acted on first, because a source turns a report into a fix. Without one the claim still gets read, but it has to be researched from scratch. Where two credible sources disagree and neither is clearly the primary one, the disputed figure is removed rather than left in place — the rules above apply to corrections as much as to first publication.
Every substantive change is dated in the changelog, including corrections. A site that quietly edits its numbers is asking to be trusted without evidence.
How often figures are re-checked
Each state page shows the date its figures were last confirmed against the sources listed on it. The most recent check across all 10 states was . States are re-checked when a legislature amends a fee, when a correction comes in, and on a rolling schedule regardless. Because fee changes are rarely announced to websites, the honest position is that this site lags the statute book — which is why the date is printed rather than buried.
Independence
This site carries advertising, and some outbound links to commercial products are affiliate links. Both are disclosed in full in the advertising and affiliate disclosure. Neither touches the editorial process described above.
Concretely, the rules that make that claim checkable:
- No advertiser, affiliate, dealer, lender or insurer sees a figure before it is published, or reviews a state page at any stage.
- No state is added, ordered, promoted or held back for commercial reasons. The publication order is set by the criteria above and nothing else.
- No fee, rate, comparison or ranking on this site is for sale, and no sponsored content is presented as editorial.
- Source citations are never affiliate links. A link to a statute or a fee schedule earns nothing and is never monetised.
- A correction is published on its merits. Whether a change helps or hurts an advertiser is not a consideration, and has never been raised.
Adverts are labelled, kept out of the calculator's result area, and never styled to look like a fee, a result or a recommendation. If the funding model changes again it will be disclosed here and dated in the changelog before it goes live.
What this policy does not cover
It does not make an estimate into a quote. The limits of what these figures can tell you — local rate variation, vehicle-specific charges, dealer documentation fees, and the fact that this site has no affiliation with any motor vehicle agency — are set out in the disclaimer.