ADA vs. WCAG vs. Section 508: What's the Difference?

Why the Confusion Exists

If you have spent any time researching web accessibility, you have encountered three terms that seem to be used interchangeably: ADA, WCAG, and Section 508. People ask whether their website is "ADA compliant" and get told to follow "WCAG guidelines." Federal contractors hear about "508 compliance" and wonder if it is the same thing. Vendors pitch "ADA and WCAG compliance" as if the two are synonymous.

The confusion is understandable because these three frameworks are deeply interconnected. But they are not the same thing. Each serves a different purpose, comes from a different source, applies to different entities, and operates through different enforcement mechanisms. Understanding the distinctions is essential for knowing exactly what your obligations are and how to meet them.

Think of it this way: the ADA is a law that says you cannot discriminate. WCAG is a technical standard that defines what accessible web content looks like. Section 508 is a federal regulation that requires government technology to meet specific accessibility standards. They work together, but they are different instruments with different scopes.

The ADA: A Civil Rights Law

The Americans with Disabilities Act is a comprehensive civil rights law enacted in 1990 and amended in 2008. It prohibits discrimination on the basis of disability in employment, state and local government services, public accommodations, commercial facilities, transportation, and telecommunications.

What the ADA Covers

The ADA is organized into five titles:

Title I covers employment — requiring employers with 15 or more employees to provide reasonable accommodations and prohibiting disability-based discrimination in hiring, firing, and working conditions.

Title II covers state and local government services — requiring that all programs, services, and activities of state and local government entities be accessible to people with disabilities.

Title III covers public accommodations — requiring that private businesses open to the public not discriminate against people with disabilities in their goods, services, and facilities.

Title IV covers telecommunications — requiring telephone and internet companies to provide relay services.

Title V contains miscellaneous provisions, including anti-retaliation protections.

The ADA and Websites

The ADA's original text does not specifically mention websites, digital content, or the internet. This is simply because the commercial internet did not exist when the law was written. However, the ADA was deliberately written in broad, technology-neutral language. It prohibits discrimination in access to "places of public accommodation" and government services without limiting those concepts to physical spaces.

Over the past decade, courts across the country have ruled that websites fall within the scope of the ADA. The DOJ has consistently taken the position that the ADA applies to web content. And the 2024 Title II final rule removed any remaining ambiguity for state and local government websites by explicitly requiring WCAG 2.1 Level AA conformance.

Who the ADA Applies To

The ADA applies to virtually every employer with 15 or more employees (Title I), every state and local government entity (Title II), and every private business that qualifies as a place of public accommodation (Title III). In the context of websites, this means the ADA covers government websites, business websites, nonprofit websites, and most other public-facing websites in the United States.

The ADA is enforced through private lawsuits, DOJ enforcement actions, and complaints filed with federal agencies. There is no certification process and no formal compliance reporting requirement.

WCAG: A Technical Standard

The Web Content Accessibility Guidelines are an international technical standard published by the World Wide Web Consortium (W3C) through its Web Accessibility Initiative (WAI). WCAG is not a law. It is not a regulation. It is a voluntary consensus standard that defines, in specific and testable terms, what accessible web content means.

What WCAG Does

WCAG provides a detailed set of success criteria organized around four principles: Perceivable, Operable, Understandable, and Robust (POUR). Each success criterion describes a specific accessibility requirement and is assigned to one of three conformance levels (A, AA, AAA).

For example, WCAG Success Criterion 1.4.3 states that text must have a contrast ratio of at least 4.5:1 against its background. This is a specific, measurable, testable requirement. There is no ambiguity about what "sufficient contrast" means — it is a mathematical ratio that can be verified with a tool.

This specificity is what makes WCAG valuable. Laws like the ADA say "be accessible" but do not define what accessible means in technical terms. WCAG provides that definition.

WCAG Versions and Levels

WCAG has evolved through several versions:

• WCAG 2.0 (2008) — The foundational modern version. Contains 61 success criteria. Still referenced by Section 508.
• WCAG 2.1 (2018) — Added 17 criteria addressing mobile, low-vision, and cognitive accessibility. Referenced by the DOJ's 2024 Title II rule.
• WCAG 2.2 (2023) — Added 9 criteria (and removed 1) addressing authentication, focus appearance, and dragging movements. The current W3C Recommendation.
• WCAG 3.0 — In development. Will use a new conformance model but is years from completion.

Each version is backward-compatible: conforming to WCAG 2.2 also means conforming to 2.1 and 2.0.

The three conformance levels are cumulative:

• Level A — Minimum baseline. Without these, content is fundamentally broken for some users.
• Level AA — The standard target for legal compliance worldwide.
• Level AAA — Enhanced accessibility. Not recommended as a blanket requirement.

Who WCAG Applies To

As a voluntary standard, WCAG does not directly "apply" to anyone in a legal sense. You cannot be sued for violating WCAG itself. However, WCAG is referenced by the laws and regulations that do apply to you. When the DOJ says websites must be accessible under the ADA, WCAG is the standard they point to. When Section 508 was revised in 2017, it incorporated WCAG 2.0 Level AA. When the European Union adopted the European Accessibility Act, it referenced standards based on WCAG.

WCAG is the de facto global standard for web accessibility compliance, regardless of which law you are operating under.

Section 508: A Federal Procurement Regulation

Section 508 is a provision of the Rehabilitation Act of 1973, as amended in 1998. It requires federal agencies to make their electronic and information technology (EIT) accessible to people with disabilities — both employees and members of the public.

What Section 508 Covers

Section 508 covers a broad range of information and communication technology (ICT) used by or procured by federal agencies:

• Websites and web applications
• Software applications
• Electronic documents (PDFs, Word documents, spreadsheets)
• Hardware (kiosks, copiers, telecommunications equipment)
• Video and multimedia content
• Mobile applications

Critically, Section 508 is a procurement standard. When federal agencies purchase, develop, or maintain technology, that technology must meet Section 508 standards. This creates a ripple effect through the technology industry: any company that wants to sell products or services to the federal government must ensure those products meet Section 508 requirements.

The Section 508 Refresh

In January 2017, the U.S. Access Board published updated Section 508 standards (often called the "Section 508 Refresh"). The refresh was a landmark change because it directly incorporated WCAG 2.0 Level A and AA success criteria as the technical standard for web content and electronic documents.

Before the refresh, Section 508 had its own set of technical standards that were separate from (though similar to) WCAG. After the refresh, the two are aligned for web content: meeting WCAG 2.0 Level AA for web content means meeting Section 508 for web content.

The refresh also adopted additional requirements for non-web ICT, such as software applications, hardware, and telecommunications products, that go beyond what WCAG covers.

Who Section 508 Applies To

Section 508 applies to:

• Federal agencies — All executive, legislative, and judicial branch agencies must ensure their ICT is accessible.
• Federal contractors and vendors — Companies that sell technology products or services to federal agencies must provide accessible products. This is typically verified through a Voluntary Product Accessibility Template (VPAT).
• Organizations receiving federal funding — Section 508 obligations can extend to state agencies, universities, and other organizations that receive federal financial assistance, though this often operates through Section 504 of the Rehabilitation Act.

Section 508 does not directly apply to private businesses that have no federal connection. If your company does not contract with the federal government or receive federal funding, Section 508 is not your concern — though the ADA likely is.

How the Three Relate to Each Other

The relationship between ADA, WCAG, and Section 508 can be understood as a hierarchy of purpose:

The ADA establishes the legal obligation. It says people with disabilities have the right to access goods, services, and information without discrimination.

WCAG provides the technical definition. It defines exactly what "accessible" means for web content, in specific, measurable terms.

Section 508 applies that definition to federal technology. It requires federal agencies and their vendors to meet WCAG-based standards for all their information and communication technology.

They converge around the same core: WCAG 2.0/2.1 Level AA. The DOJ uses WCAG to evaluate ADA compliance. Section 508 incorporates WCAG directly. International laws reference WCAG as well. WCAG is the common thread.

Side-by-Side Comparison

Type: ADA is a civil rights law. WCAG is a technical standard. Section 508 is a federal regulation.

Issued by: ADA was enacted by Congress. WCAG is published by the W3C. Section 508 standards are maintained by the U.S. Access Board.

Year: ADA was enacted in 1990 (amended 2008). WCAG 2.2 was published in 2023. Section 508 was added to the Rehabilitation Act in 1998 (refreshed 2017).

Scope: ADA covers all aspects of disability discrimination (employment, government services, public accommodations). WCAG covers web and digital content accessibility. Section 508 covers federal information and communication technology.

Who it applies to: ADA applies to employers, government entities, and private businesses open to the public. WCAG is voluntary (but referenced by laws). Section 508 applies to federal agencies, contractors, and federally funded organizations.

Technical standard: ADA does not specify one directly (courts and DOJ reference WCAG). WCAG is the technical standard itself. Section 508 incorporates WCAG 2.0 Level AA for web content.

Enforcement: ADA is enforced through lawsuits and DOJ action. WCAG has no enforcement mechanism of its own. Section 508 is enforced through federal procurement policies, agency complaints, and lawsuits under the Rehabilitation Act.

Common Scenarios: Which Applies to You?

You are a private e-commerce company. The ADA (Title III) applies to your website. Section 508 does not, unless you sell to the federal government. You should follow WCAG 2.1 or 2.2 Level AA to demonstrate ADA compliance.

You are a city government. ADA Title II applies, and the DOJ's 2024 final rule requires WCAG 2.1 Level AA conformance. If you receive federal funding (most cities do), Section 504 of the Rehabilitation Act may also apply.

You are a software company selling to federal agencies. Section 508 directly applies to your products. You will need to produce a VPAT documenting your conformance. For web-based products, this means meeting WCAG 2.0 Level AA (and ideally 2.1 or 2.2).

You are a public university. ADA Title II applies (you are a state entity). Section 504 applies (you receive federal funding). Section 508 may apply to technology you procure. WCAG 2.1 Level AA is the standard across all of these.

You are a private healthcare provider. ADA Title III applies (you are a place of public accommodation). If you accept Medicare or Medicaid, Section 504 applies as well. Your patient portal, website, and digital documents should meet WCAG 2.1 Level AA.

You are a nonprofit food bank. ADA Title III likely applies if you serve the public. If you receive federal grants, Section 504 applies. WCAG 2.1 Level AA is the appropriate standard.

What About Section 504?

Section 504 of the Rehabilitation Act predates the ADA and prohibits disability discrimination by organizations that receive federal financial assistance. It is frequently overlooked but has broad reach: any school, university, hospital, nonprofit, or state agency that receives federal grants, contracts, or other funding is covered.

Section 504 is enforced by the federal agency that provides the funding. For healthcare organizations, that is the Department of Health and Human Services. For educational institutions, it is the Department of Education. These agencies can investigate complaints, conduct compliance reviews, and withhold funding from non-compliant organizations.

While Section 504 does not specify WCAG directly, enforcement agencies increasingly interpret it to require web accessibility consistent with WCAG standards.

What About State Laws?

Several states have enacted their own digital accessibility laws that add to (but do not replace) federal requirements:

California's Unruh Civil Rights Act has been used extensively in web accessibility lawsuits. It allows statutory damages of $4,000 per violation per visit, which can add up rapidly.

New York state and city laws have been used as additional legal bases for accessibility lawsuits, contributing to New York's position as the state with the most ADA web accessibility filings.

Colorado's HB21-1110 specifically requires state and local government websites to conform to WCAG 2.1 Level AA.

Other states including Illinois, Maryland, and Minnesota have laws or policies addressing digital accessibility.

State laws can create additional obligations and additional legal exposure beyond what the ADA and Section 508 require. They typically reference WCAG as the technical standard.

Which Standard Should You Follow?

For the vast majority of organizations, the answer is simple: follow WCAG 2.2 Level AA. Here is why:

WCAG 2.2 is the most current W3C Recommendation. It is backward-compatible with 2.1 and 2.0. Meeting WCAG 2.2 Level AA means you automatically satisfy the WCAG 2.0 Level AA requirements referenced by Section 508 and the WCAG 2.1 Level AA requirements referenced by the DOJ's Title II rule.

By targeting WCAG 2.2 Level AA, you are positioning your organization for compliance with the ADA, Section 508, the European Accessibility Act, and the accessibility laws of most other jurisdictions — all with a single standard.

Do not get paralyzed by the complexity of overlapping laws and standards. They all point to the same destination.

Key Takeaways

The ADA is the law — it establishes that people with disabilities have a legal right to access your website. WCAG is the standard — it defines what accessible web content actually looks like in measurable terms. Section 508 is the federal regulation — it requires government technology to meet WCAG-based standards.

For most organizations, the practical guidance is the same regardless of which framework applies to you: conform to WCAG 2.2 Level AA. Doing so gives you the strongest possible position under the ADA, Section 508, state laws, and international accessibility regulations.

The three frameworks are not competing requirements. They are layers of the same system, all pointing toward the same goal: a web that works for everyone.