For many Deaf people, particularly those who are born deaf or became deaf early in life, written language is a second language. Their first language is a sign language: British Sign Language (BSL), American Sign Language (ASL), or one of many other national sign languages.
Captions are text. For some Deaf users, reading captions is effortful in a way that sign language interpretation is not. WCAG 1.2.6 recognises this and requires that prerecorded synchronised media (video with audio) includes a sign language interpretation.
This is Level AAA, the highest WCAG conformance level. Most organisations target Level AA. You will not fail a standard web audit for missing 1.2.6 unless your target is explicitly AAA. But for public sector bodies, government services, and organisations serving Deaf communities, this is worth understanding and planning for.
| Field | Details |
| WCAG Criterion | 1.2.6 |
| Conformance Level | Level AAA |
| Principle | Perceivable |
| WCAG Version | 2.1 |
| Official Reference | https://www.w3.org/WAI/WCAG21/Understanding/1-2-6 |
The WCAG 1.2.6 Concept in Plain Terms
Sign language interpretation for video means showing a signer on screen, typically a picture-in-picture window, translating the spoken audio into sign language in real time throughout the video.
This is not the same as captioning. A caption reader needs English literacy. A sign language user may not have strong written English skills, particularly if they are part of a Deaf cultural community where sign is the primary language. For these users, sign language interpretation is not just a preference; it is genuinely more accessible than captions.
Who Does WCAG 1.2.6 Actually Affect?
If you fail to meet basic WCAG 1.2.6 requirements, you exclude the following people:
- Deaf users whose first language is BSL, ASL, or another national sign language
- Deaf users who struggle with reading dense or technical written English
- Deaf community organisations, public bodies addressing Deaf audiences, and services with a known Deaf user base
In the UK, BSL received legal recognition under the British Sign Language Act 2022. In the US, ASL is recognised as a full language. Organisations serving public audiences should be aware of the linguistic rights of Deaf communities.
Common Failures Associated with WCAG 1.2.6
There are a few common failures that arise with WCAG 1.2.6. Let’s take a closer look:
No sign language provision at all
This is the most common situation, and many organisations simply have not considered this. For Level AA, this is not a WCAG failure. For AAA targets, it is.
Poor quality interpretation
A sign language interpreter who is not fluent, who signs at a poor position relative to the camera, or whose hands are not clearly visible does not meet the requirement. Quality of interpretation matters.
Interpretation window too small
If the interpreter is shown in a small corner of the screen and their signing is unclear because of low resolution or cramped space, the interpretation is not usable.
How to Fix It WCAG 1.2.6 Issues
Here are a few strategies to implement when trying to address WCAG 1.2.6 issues:
- Identify videos where sign language interpretation is a priority, including public-facing content, legal or rights-related information, and health information
- Commission a qualified, fluent sign language interpreter for the relevant sign language (BSL for UK, ASL for US, etc.)
- Record the interpreter as a picture-in-picture overlay on the video, or as a side-by-side version
- Ensure the interpreter is well-lit, clearly visible, and large enough on screen to read
- Publish the signed version clearly alongside the original
Note: There is no single universal sign language. BSL and ASL are distinct languages, as are Auslan, ISL, and others. If you serve international audiences, consider which sign language is most relevant for your primary user base.
Edge Cases Worth Knowing
There are a few edge cases that you should know about:
- Pre-existing video library: Retrofitting sign language interpretation onto a large content library is expensive. Prioritise new content and high-importance legacy content.
- Short vs long videos: The cost of sign language interpretation scales with video length. A short 90-second announcement is more achievable than a two-hour lecture series.
- User-generated content: If your site hosts user-generated video content, you are not typically responsible for providing sign language interpretation for that content.
How to Test for WCAG 1.2.6
If you want to identify WCAG 1.2.6 issues, there are a few methods:
- Identify all prerecorded synchronised media on the site
- Check whether a sign language interpreted version is available
- If it is: assess whether the interpreter is clearly visible and the interpretation quality is adequate
- Check whether the signed version is clearly labelled and easy to access
Why This Matters Beyond a Checkbox
Sign language is a rich, fully developed language, not a simplified version of written English. Treating sign language access as an edge case misrepresents the reality of Deaf people’s communication needs.
For organisations that serve Deaf communities directly, this is not a nice-to-have; it is fundamental to equal access.
WCAG 1.2.6 Quick Fix Checklist
Alright, time to make your digital content WCAG 1.2.6 compliant. Here’s a helpful checklist:
- High-priority video content has a sign language interpreted version
- The interpreter is clearly visible, well-lit, and large enough to read on screen
- The correct sign language is used for the primary audience (BSL/ASL/other)
- Signed versions are clearly labelled and easy to find
- New video productions have a process for commissioning sign language interpretation
WCAG 1.2.6 Sign Language (Prerecorded) FAQs
Looking for a quick recap? Here are answers to some of the most frequently asked questions on this topic:
No. 1.2.6 is Level AAA. Most organisations and most legal frameworks require Level AA. Unless you are explicitly targeting AAA, 1.2.6 is best practice rather than a compliance requirement.
Use the sign language of your primary audience. For UK audiences, that is BSL. For US audiences, ASL. If you serve international audiences, consider which sign languages are most relevant.
AI sign language avatars exist but vary widely in quality and accuracy. Some Deaf communities have expressed concerns about their cultural authenticity and linguistic accuracy. Human interpreters remain the preferred approach, especially for anything sensitive or complex.
If you publish recordings of meetings, webinars, or events as video content on your site, yes — if you are targeting AAA. For most organisations, the practical answer is to provide sign language interpretation at live events and consider it for high-priority published recordings.