Section 508 vs ADA vs WCAG: Which Applies to You?

The three names get used interchangeably in sales pitches and RFPs, which is how organizations end up building to the wrong version or assuming a deadline that does not apply to them. The quickest way through is to separate the standard from the laws, then find your row in the table below.

Which applies to you

Find the row that describes your organization. Each source is the primary document, linked.

WCAG: the standard everything points to

The Web Content Accessibility Guidelines are published by the W3C. They are not a law. They define testable success criteria at three levels, A, AA and AAA, and every law in the table adopts or references them. The current version, WCAG 2.2, became a W3C Recommendation on 5 October 2023 with 55 success criteria at Levels A and AA combined. It added nine criteria, including 2.5.8 Target Size (Minimum) and 3.3.8 Accessible Authentication (Minimum) at AA, and W3C notes that “4.1.1 Parsing is obsolete and removed from WCAG 2.2.” The full list is in our WCAG 2.2 checklist, and the version differences are in WCAG 2.1 vs 2.2.

Section 508: federal agencies and what they buy

Section 508 of the Rehabilitation Act applies to all federal agencies “when they develop, procure, maintain, or use electronic and information technology.” The Revised 508 Standards from the U.S. Access Board took effect January 18, 2018. Provision E205.4 of the ICT standards says: “Electronic content shall conform to Level A and Level AA Success Criteria and Conformance Requirements in WCAG 2.0”.

Private companies meet Section 508 indirectly. Federal acquisition rules require agencies to put the accessibility standards in their requirements, so a vendor selling software or web services to an agency is building to those requirements.

The ADA: two titles, two different situations

Title II covers state and local governments. The DOJ’s 2024 web and mobile rule names WCAG 2.1 Level AA as the technical standard, including for content provided through contractors. An interim final rule published April 20, 2026 moved the compliance dates to April 26, 2027 for governments with a total population of 50,000 or more and to April 26, 2028 for smaller governments and special districts. The standard did not change. Details, including the five exceptions, are in our ADA Title II web rule guide and the ADA Title II glossary entry.

Title III covers businesses open to the public. The DOJ’s March 18, 2022 guidance says the ADA applies to what those businesses offer on the web, names WCAG and the Section 508 Standards as helpful guidance, and says businesses have flexibility in how they comply. There is no technical regulation and no deadline. We cover that in does the ADA apply to business websites.

If you sell to consumers in the EU

The European Accessibility Act applies to covered products placed on the market and covered services provided to consumers after 28 June 2025, including e-commerce and consumer banking services. Microenterprises providing services are exempt. It is a separate regime from the U.S. laws above; see the European Accessibility Act for U.S. businesses.

What to build to

Because the versions nest, one target covers almost everything: WCAG 2.2 Level AA. W3C says the 2.0 and 2.1 criteria are essentially the same in 2.2, with the single exception of the removed 4.1.1 Parsing. Build to 2.2 AA, check 4.1.1 separately if a contract names 2.0 or 2.1 verbatim, and document what you tested. Our free accessibility checker is a starting point; automated tools find only part of what WCAG covers.

Frequently asked questions

About the work

Webvello is a web development and AI search company founded in 2024, based in Roseville, California, with 50+ projects across 37+ cities. We run accessibility audits and remediation against WCAG 2.1 and 2.2 AA and build new sites with accessible components from the start.

This page is general information, not legal advice. Sources are linked in each section and were checked on October 17, 2026.