Accessibility mistakes that hurt SEO and conversion: the 5 fixes
CRO and LLM Optimiser
What is accessibility?
Accessibility means designing and building websites so people can use them regardless of disability or circumstance, including visual, hearing, motor, and cognitive impairments.
Accessibility is not just compliance. It is about building digital experiences that work reliably for everyone.
Key disabilities to consider (what they mean in practice)
Visual impairments
- Blindness: users may rely on screen readers
- Low vision: users may rely on magnification or high-contrast settings
- Colour blindness: users may not distinguish certain colours, so do not rely on colour alone and ensure sufficient contrast
Hearing impairments
- Deafness: captions or transcripts are required for audio and video
- Hearing loss: similar needs, plus assistive devices
Motor impairments
- Limited dexterity: keyboard navigation or alternative inputs
- Paralysis: voice control, switch devices, and predictable focus order
Cognitive and learning disabilities
- Dyslexia: readable fonts, clear layout, predictable navigation
- Attention deficits: minimal distractions and clear hierarchy
- Memory impairments: simple flows and clear signposting
Seizures (e.g. epilepsy)
- Avoid rapid flashing and give users control over motion.
The business case for web accessibility
Accessibility is a conversion and retention lever.
- If people cannot navigate your site, they leave.
- If your site creates friction, conversion drops.
- If your content is poorly structured, search engines struggle to understand it.
Google has said accessibility is not a direct ranking factor, but accessibility improvements often overlap with user experience signals that affect search performance (engagement, clarity, structure).
‘Many organisations are waking up to the fact that embracing accessibility leads to multiple benefits, reducing legal risks, strengthening brand presence, improving customer experience and colleague productivity.’
Paul Smyth, Head of Digital Accessibility, Barclays
The global disability market is large
The World Health Organisation estimates 16% of the global population lives with a significant disability. (WHO: Disability and health)
Accessibility directly impacts conversion
Most sites still fail basic standards. WebAIM reports that 95.9% of homepages fail to meet WCAG 2 standards. (WebAIM Million)
If a site is hard to use, people abandon it. Level Access reports that many users with disabilities leave inaccessible sites immediately. (State of digital accessibility)
Accessibility is cheaper when done early
The W3C’s business case is clear: building accessibly from the start costs far less than retrofitting. (W3C business case)
Top accessibility mistakes hurting your website (and how to fix them)
Each section includes:
- what the mistake is
- why it impacts accessibility
- how it impacts SEO and conversion
- how to test it
1) Missing semantic HTML and heading structure
What it is: using the wrong elements for structure (or skipping heading levels), especially common with page builders.
Why it affects accessibility: screen readers use headings to navigate. If the hierarchy is broken, users lose the map.
Why it affects SEO and conversion: headings help search engines understand topic structure. Clear structure also improves readability and reduces bounce.
How to test:
- Use WAVE to spot structural issues: WAVE
- Inspect headings in DevTools
- Test with a screen reader: NVDA (Windows) or VoiceOver (Mac)
2) Missing or misused ARIA
ARIA (Accessible Rich Internet Applications) adds accessibility information for dynamic UI components.
What to remember: ARIA is a bridge, not a replacement for semantic HTML. Use native elements first.
Common attributes (use sparingly and correctly):
aria-labelfor icons or controls without visible textaria-expandedfor toggles (menus, accordions)aria-describedbyfor help text and errorsaria-livefor dynamic notifications
Reference: W3C ARIA overview
3) Poor keyboard navigation and focus management
What it is: users cannot complete tasks using only a keyboard, or focus order is confusing.
Why it affects accessibility: many users rely on keyboard navigation or assistive tech.
Why it affects SEO and conversion: if users cannot navigate, they abandon. That kills leads and engagement.
How to test:
- Navigate your site using only Tab, Shift+Tab, Enter, and Escape
- Ensure focus is visible and logical
- Run audits in Lighthouse/PageSpeed
4) Inadequate colour contrast
What it is: text does not have enough contrast against its background.
Why it affects accessibility: low contrast makes content unreadable for many users.
Why it affects SEO and conversion: unreadable content increases bounce and reduces trust.
How to test:
- Use WebAIM Contrast Checker: Contrast checker
- Run WAVE or Lighthouse accessibility audits
5) Missing text alternatives (alt text)
What it is: images and media without meaningful text alternatives.
Why it affects accessibility: screen reader users miss content.
Why it affects SEO: alt text helps search engines understand images and can improve image visibility.
How to test:
- Run WAVE or Lighthouse
- Manually review key pages and templates
Key takeaways
- Accessibility is not just compliance, it is usability and revenue protection.
- Fix structure, keyboard access, contrast, and alt text first. These are high impact and easy to test.
- Build accessibility into templates early. Retrofits are more expensive.
Want a quick accessibility + conversion audit of your site?
If you want to know what’s actually broken (and what to fix first), start with a free site audit. I’ll review your key templates for accessibility blockers, conversion friction, and the technical issues that quietly tank SEO performance.
