Does your license number have to be on your website?

In most licensing states, yes. The rule is usually written as “your license number must appear in all advertising”, and a website is advertising. Minnesota's statute names websites explicitly, Oregon's says internet advertising must show the number visually, Florida's says the number goes in every advertisement regardless of medium, and California's definition covers any electronic transmission. The states that do not require it tend to be the ones with no statewide contractor license at all, where the duty may still exist at city or county level.

That question was settled by the way the statutes are written. They define advertising by function — a commercial message offering your services — not by format, and most of the definitions were drafted broadly enough to survive new media. California's regulation lists “airwave or any electronic transmission”; Massachusetts covers “any commercial message” in a long list that ends with any sign or display. A page that says what you do and invites people to hire you is a commercial message.

The footer of every page is the simplest way to satisfy every version of the rule at once. Pennsylvania's law does not say where it goes, only that it must be clearly visible; California is more pointed, and treats a number reachable only through a separate link as not being in the advertisement. A sitewide footer means you never have to argue about which page counted as the ad.

Those are advertisements by the same definitions, and they are usually the ones customers actually see first. Most profiles give you a description field or a short bio that will hold the line. This is also the practical reason to keep one canonical disclosure line: you paste the same text everywhere instead of writing a different one per platform.

It depends on the state, and this is the item that varies most. Massachusetts includes “any interior or exterior sign or display, including on a vehicle” in its definition. California names lettering on vehicles registered in this or any other state. Washington does the opposite and expressly says signs on motor vehicles and on-premises signs do not count as advertising under that section. Arizona lets you skip vehicle signage if the ad shows a web address whose site displays your name and number.

That is the most common near-miss. California's guidance is that the number must be in the advertisement itself and not exclusively in fine print reachable through a separate link. A dedicated licensing page is one click away from the advertisement, which is the thing the rule is trying to prevent. A footer costs you nothing and removes the argument.

No, and this is worth being precise about. It means we did not verify one against the statute, so we are not going to state one. Plenty of trades are licensed at city or county level even where the state has no general contractor license — Texas is the clearest example, where the state licenses electricians, plumbers and HVAC through TDLR but leaves general remodeling to municipalities. Check with the authority that issued your license.

It is usually a citation with a civil penalty rather than anything dramatic, and boards do enforce it: California's CSLB runs a complaint form aimed specifically at illegal advertising, and its citations carry civil penalties. The more serious exposure is advertising for work that requires a license when you do not hold one, which California treats as a misdemeanor. Amounts and procedures vary by state, so check your board before assuming a number you read online applies to you.

List each one. Contractors who work across a state line normally run a footer that names both registrations, because each state's rule applies to advertising directed at people in that state. New Jersey's regulation, for example, is written about advertisements distributed within the State. One footer with two lines satisfies both and costs nothing.