Where accessibility and SEO overlap, and where they do not

7 days ago
3 min read

Updated: 19 hours ago

Introduction

Two separate projects are proposed. One is an accessibility review, usually framed as compliance, and one is a search improvement, framed as marketing. They are scheduled separately, budgeted separately, and often prioritised against each other.

A substantial part of the work is identical. Both depend on content being structured, described in text and reachable without a mouse, because a screen reader and a crawler encounter a page in similar ways. Recognising the overlap gets more done for the same money, provided nobody pretends the two are the same thing.

1. Where accessibility and SEO overlap is in the underlying structure

The largest shared area.

Proper heading hierarchy, meaningful landmarks and a logical reading order help somebody navigating by structure and help a crawler understand what a page covers. Fixing headings once serves both, and it is usually the single most productive shared task.

2. Text alternatives serve both audiences

The most familiar example.

Alt text describes an image to a person who cannot see it and to a system that cannot interpret it. The same sentence does both jobs, which is why writing it for the human case produces the better result for the other one automatically.

3. Descriptive link text helps everybody

A small change with two benefits.

People navigating by links hear them out of context, so read more and click here convey nothing. Descriptive text tells them where the link goes and simultaneously tells a search engine what the destination is about.

4. Video and audio need transcripts either way

Content that otherwise does not exist.

Captions and transcripts make media usable for people who cannot hear it, and they are the only way the content becomes text that can be indexed or searched. This is one of the clearest cases where a single piece of work satisfies two requirements completely.

5. Clear, plain language is a shared requirement

Frequently overlooked as an accessibility matter.

Simple sentences and defined terminology help people with cognitive differences, people reading in a second language, and anybody scanning quickly. It also matches how people actually search, which is rarely in industry vocabulary.

6. Page speed matters to both

For different reasons that point the same way.

Assistive technology on older devices struggles with heavy pages, and slow pages lose visitors and influence rankings. The work is identical whichever justification funds it.

7. Understand what does not overlap

The honest limit of the argument.

Colour contrast, keyboard focus indicators, form labelling and support for assistive software have no search benefit whatsoever. They are required for people to use your site, and they must be done on their own merits rather than being smuggled in under a marketing budget.

8. Treat accessibility as an obligation, not a tactic

The framing that matters.

In many jurisdictions this is a legal requirement, and in all of them it determines whether a substantial share of the population can use your site. Presenting it as a search tactic makes it vulnerable to being deprioritised the moment the search argument weakens.

9. Start with the shared items

Sequencing that gets the most done.

Headings, alt text, link text and transcripts are cheap, benefit both, and can usually be done without a developer. They also demonstrate progress, which makes the specialist work easier to fund afterwards.

Automated checkers find only a fraction of accessibility problems. A page can pass every automated test and remain unusable with a keyboard or a screen reader, so testing with actual assistive technology, or with people who rely on it, is the only way to know where you genuinely stand.

Conclusion

Recognise that structure, text alternatives, link wording and transcripts serve accessibility and search simultaneously.

Fix heading hierarchy first because it is the largest shared benefit, write alt text for the human case and let search benefit follow, use descriptive link text, produce captions and transcripts for media, write in plain language, improve page speed for both reasons at once, accept that contrast, keyboard support and form labelling have no search benefit and must be justified independently, treat accessibility as an obligation rather than a tactic, and remember that automated tools catch only part of the problem.