Web accessibility means designing and building a website so that disabled people can perceive, understand, navigate and use it, whether they are blind and using a screen reader, have low vision, cannot use a mouse, are deaf, or have a cognitive or learning disability. WCAG, the Web Content Accessibility Guidelines published by the W3C, is the internationally recognised standard for measuring it. The current version is WCAG 2.2, and level AA is the benchmark most UK organisations aim for.
How WCAG works
WCAG is organised around four principles: content must be perceivable, operable and understandable, and the code must be sound enough to work reliably with assistive technology such as screen readers and voice control. Under those sit testable success criteria, each graded A (the minimum), AA or AAA. Meeting AA means passing every A and AA criterion.
In practice, many criteria come down to familiar things. Images need alt text so a screen reader can describe them. Text needs enough colour contrast against its background, at least 4.5:1 for normal-sized text at AA. Every function must work from a keyboard, with a visible focus outline showing where you are. Form fields need proper labels, and errors must be explained in words, not just shown in red. Videos need captions.
WCAG 2.2, published in October 2023, added criteria that matter on everyday business sites: interactive targets such as buttons should be at least 24 by 24 CSS pixels or well spaced, a sticky header or banner must not completely hide the item that has keyboard focus, and logging in should not depend on memorising or retyping a code without help such as paste or a password manager.
Why it matters for a UK business
The Equality Act 2010 requires service providers to make reasonable adjustments so disabled people are not put at a substantial disadvantage, and that duty extends to services offered through a website. The Act does not name WCAG, but WCAG 2.2 AA is the benchmark accessibility auditors most commonly use to judge whether a site works for disabled people. The Public Sector Bodies Accessibility Regulations 2018, which require a published accessibility statement, apply to public bodies only, not to private businesses.
The commercial case is simpler. A visitor who cannot complete your booking form with a keyboard, or cannot read pale grey text on a phone in sunlight, leaves. Much of the same work also helps search: descriptive headings, alt text, clear link text and well-structured HTML make a page easier for search engines to interpret as well as for people.
Common mistakes
- Buying an overlay. A widget that adds a toolbar to the page does not fix the underlying code, and screen reader users often find these tools get in the way.
- Testing only with automated tools. Scanners catch a fraction of the issues. Keyboard testing and a screen reader check find the rest.
- Placeholder text instead of labels. The hint disappears as soon as someone starts typing.
- Links called “here”. Screen reader users often browse a list of links, and twenty links reading “here” tell them nothing.
- Brand colours that fail contrast. A light orange or grey that looks elegant on a monitor can be unreadable for many people.
- Cookie banners and pop-ups that trap keyboard focus or cannot be closed without a mouse.
How to act on it
Pick your most important journeys, such as finding a service, contacting you and buying, and try each one using only the Tab, Enter and arrow keys. Run the pages through a free checker such as WAVE or axe and fix contrast, missing labels and missing alt text first. Then test with a screen reader: VoiceOver is built into Macs and iPhones, and NVDA is free on Windows.
Accessibility is cheapest to get right when a site is being designed, because colours, components and templates are still open to change. When I work on a website redesign, WCAG 2.2 AA is written into the brief from the first wireframe.