“Section 508,” “WCAG,” and “ADA” get used interchangeably in accessibility conversations — but they are three different things, and knowing which one applies to you is the first step to compliance. One is a set of technical guidelines. The others are laws. Here is how they fit together.
WCAG: the technical standard everyone references
The Web Content Accessibility Guidelines are maintained by the World Wide Web Consortium (W3C). They are organized around four principles — content must be Perceivable, Operable, Understandable, and Robust (POUR) — and broken into testable “success criteria” at three conformance levels: A (minimum), AA (the legal target almost everywhere), and AAA (aspirational). When a law requires “accessibility,” it almost always does so by pointing at a specific WCAG version and level. WCAG itself is not a law; it is the ruler the laws measure against.
Section 508: the federal IT law
Section 508 of the Rehabilitation Act requires federal agencies to make their electronic and information technology — websites, documents, software, kiosks, and more — accessible to people with disabilities. The 2018 “508 Refresh” aligned the technical requirements with WCAG 2.0 Level AA. If you are a federal agency, or you sell IT to one, or you run a program funded by federal dollars that flow through a 508-obligated entity, Section 508 is your standard.
The ADA: the civil-rights law with the biggest reach
The Americans with Disabilities Act prohibits discrimination on the basis of disability. Two titles matter for the web:
- Title II covers state and local governments. In 2024 the Department of Justice published a rule adopting WCAG 2.1 Level AA as the required standard for their websites and mobile apps, with compliance dates of April 26, 2027 and April 26, 2028.
- Title III covers private businesses that are “places of public accommodation.” There is no numeric web regulation here yet, but courts have repeatedly treated WCAG 2.1 AA as the practical benchmark in accessibility lawsuits.
Which standard applies to you?
- Federal agency or contractor: Section 508 → WCAG 2.0 AA (build to 2.1 AA to stay ahead).
- State or local government (agency, city, county, school district, special district): ADA Title II → WCAG 2.1 AA by the deadlines above.
- Healthcare provider receiving federal funds: Section 1557 of the ACA and Section 504 of the Rehabilitation Act — the HHS Section 504 digital-accessibility deadline is May 11, 2027.
- Private business: ADA Title III — no fixed regulation, but WCAG 2.1 AA is the defensible target.
The good news: they converge
You do not have to reconcile three different rulebooks. Whatever your obligation, the practical answer is the same: conform to WCAG 2.1 Level AA, document the work, and keep it current. Meeting WCAG 2.1 AA satisfies Section 508's 2.0 AA baseline and the ADA Title II standard simultaneously. Build to that target once and you have covered every version of the requirement.
Not sure which standard governs your organization — or how far your current site is from it? We assess your websites and document libraries against WCAG 2.1 AA and give you a prioritized, documented remediation plan.