Why Is WCAG Level AA the Standard for Digital Accessibility?

When you’re building an accessibility initiative, it’s a good idea to establish your goals up front — and most accessibility experts will tell you that means seeking Level AA conformance with the Web Content Accessibility Guidelines (WCAG).

If you’re new to web accessibility, WCAG is the international consensus standard. It’s divided into three levels of conformance:

• Level A: The least strict level of conformance (conformance in this context simply means voluntary compliance).
• Level AA: Contains all of the requirements from Level A, along with additional requirements.
• Level AAA: The most strict level of conformance, containing all of the requirements from Levels A and AA, along with additional requirements.

When we discuss those levels with clients, we’ll often get questions about those other conformance levels. Most frequently, we’ll hear “why can’t we just do Level A?” from leaders who have concerns about the cost of accessible design (though we’re quick to point out that accessibility is an investment, not a cost).

But Level AA is the effective standard for a reason. Here’s why it’s the best goal for your organization — and why those other levels are still important in certain situations.

Related: Why WCAG Conformance Doesn’t Mean “Perfectly Accessible”

WCAG Level A is a baseline, but it's not ideal

So, why not just meet Level A criteria?

Level A success criteria address only the most critical barriers, such as ensuring basic keyboard navigation and providing alternative text for images. If your site meets Level A, it achieves a barebones level of accessibility — but omits many requirements that are essential for a functional user experience.

Put simply: If your website only meets Level A, you are likely still excluding a significant portion of your audience. Level AA introduces specific requirements that significantly improve usability, including:

• Contrast (Minimum) (Success Criterion 1.4.3): Level A does not have a requirement for color contrast. Without Level AA, a person with low vision or color blindness might find your text impossible to distinguish from its background. Level AA requires a contrast ratio of at least 4.5:1 for standard text, which ensures readability for many more users.
• Focus Visible (Success Criterion 2.4.7): While Level A requires that a site can be navigated with a keyboard, it does not require that the user can determine which element they have selected. Level AA ensures that a visible border or highlight appears around links and buttons during navigation, which is vital for people with motor disabilities who rely on a keyboard alone (no mouse).
• Resize Text (Success Criterion 1.4.4): Level AA requires that users can scale text up to 200 percent without using assistive technology and without losing content or functionality. For many people with visual impairments, this functionality is the difference between a usable site and one that is completely blocked.

If you’re looking for a practical argument for meeting Level AA, it’s this: Level A does not provide the same reliable legal protection as higher levels of conformance. Most international laws and U.S. court interpretations point toward Level AA as the expected standard for non-discrimination.

The challenges of Level AAA conformance

On the other end of the spectrum, Level AAA is the most rigorous tier of WCAG. However, it’s often not recommended as a sitewide goal because some criteria are virtually impossible to meet for certain types of content:

• Success Criterion 3.1.5 (Reading Level): This requires that text does not require reading ability more advanced than a lower secondary education level. For a medical research journal, a law firm, or a technical engineering site, meeting this goal is impossible without removing the necessary professional precision.
• Success Criterion 1.2.6 (Sign Language): This requires sign language interpretation for all prerecorded audio content. For organizations with vast archives of video content — such as a university with thousands of recorded lectures — the logistical and financial cost of providing human signers for every video is often unfeasible.
• Enhanced Contrast (Success Criterion 1.4.6): This mandates a 7:1 contrast ratio for all text. For many brands, this requirement can severely limit design palettes and visual branding in ways that Level AA (4.5:1) does not.

Instead of aiming for full Level AAA, many experts recommend selecting individual AAA criteria — such as avoiding flashing content entirely — that make sense for your specific audience.

Related: The Americans with Disabilities Act Is 35 Years Old — And More Relevant Than Ever

Establishing your digital accessibility goals

Setting a clear goal is the first step toward building a more inclusive digital presence. While Level AA is the de facto standard for compliance with the ADA and other global regulations, your strategy should focus on the impact your changes have on real people.

An accessibility-first mindset helps you move beyond a simple checklist. By aiming for the latest standards — currently WCAG 2.2 Level AA — you can expand your market reach, improve SEO, and provide a better experience for every visitor.

The Bureau of Internet Accessibility (BOIA) provides the expertise, audits, and strategic plan necessary to help your organization achieve and maintain long-term digital accessibility. If you are ready to define your goals and start your journey toward conformance, send us a message.