Title III covers places of public accommodation, which is most private businesses that serve the public; Title II covers state and local government. Neither names a website in the statute, which is the source of most of the confusion, and both have been applied to websites repeatedly by courts and by the Department of Justice's own guidance. This page is what each title binds, what the guidance says a business should do, and what that means for the site you own. It is not legal advice and it is not a substitute for asking your own lawyer.
Title III, and what public accommodation covers
Title III applies to private businesses in the twelve categories the statute lists: shops, restaurants, hotels, professional offices, banks, healthcare providers, schools and the rest. If your business is one of them, the Department of Justice's guidance is that its website has to be accessible, and points at WCAG as the practical measure rather than setting a separate technical standard for private sites.
Title II, and why the rules there are firmer
Title II binds state and local government, and in 2024 the Department of Justice issued a rule setting WCAG 2.1 Level AA as the technical standard for their web content, with compliance dates by entity size. If you sell to a city or a state agency, that rule reaches you through the contract even though the title itself does not bind you.
What this means for the site you own
Aim at WCAG Level AA, keep the evidence, publish a statement, and fix the paths a customer complains about first. On the worked example that is 401 issues, 167 hours and $15,872 to clear, and the first quarter of it covers everything a demand letter has ever named.
Questions people ask about ada title iii
Is there an ADA certification for websites?
No. Nobody can certify a website as ADA compliant, and a supplier offering a certificate is selling a badge.
Does the ADA apply to a business with no physical premises?
Courts have split on it, and the practical answer most businesses take is to comply anyway: the cost of the fix is smaller than the cost of being the test case.
Is this legal advice?
No. It is what the public guidance says and what the standard asks for. The letter on your desk is for your lawyer.