When advocating accessible web practices for a commercial website, the question of “what does the law require us to do?” invariably arises.
The appropriate answer to that question should really be that it doesn’t matter. Regardless of the law there is a moral imperative to do the right thing unless you are OK with excluding people, making their web experiences unnecessarily painful, and generally flouting the web’s founding principles.
However as Web Usability’s article What is the law on accessibility? helpfully advises, in the UK the legal situation is as follows:
“The accessibility of a UK web site is covered by the Equality Act 2010” (which states that) “Site owners are required to make ‘reasonable adjustments’ to make their sites accessible to people with disabilities”. While “there is no legal precedent about what would constitute a ‘reasonable adjustment’”, “given that the Government has adopted the WCAG 2.1 level AA as a suitable standard for public sector sites and it is more broadly recognised as a ‘good’ approach, any site which met these guidelines would have a very strong defence against any legal action.”
So, WCAG 2.1 Level AA is the sensible accessibility standard for your commercial UK-based website to aim for.
While not aimed specifically at the UK market, deque.com’s article What to look for in an accessibility audit offers similar advice:
The most common and widely-accepted standard to test against is WCAG, a.k.a. Web Content Accessibility Guidelines. This standard created by the World Wide Web Consortium (W3C) defines technical guidelines for creating accessible web-based content.
WCAG Success Criteria are broken down into different “levels of conformance”: A (basic conformance), AA (intermediate conformance), and AAA (advanced conformance). The current standard for compliance is both WCAG 2.1 Level A and AA.
If you don’t have specific accessibility regulations that apply to your organization but want to avoid legal risk, WCAG 2.1 A and AA compliance is a reasonable standard to adopt.