What Is Closed Captioning? Definition, Laws (ADA/WCAG/CVAA), Formats & Standards (2026)

Closed captions include speaker IDs and non-speech audio cues (music, laughter, sound effects) and assume same-language dialogue for viewers who cannot hear the audio. Subtitles translate dialogue for foreign-language viewers but typically omit sound effects and speaker labels. In streaming (Netflix, etc.) the terms are often used interchangeably as "CC" and "SDH" (Subtitles for the Deaf and Hard-of-Hearing).

Depends on who you are. Broadcast TV: yes, under FCC rules dating to 1993 and reinforced by FCC Report and Order 11-36 (2012). Federal agencies: yes, under Section 508 (revised 2018). State/local governments: yes, under DOJ Title II Final Rule (published April 24, 2024), with compliance by April 24, 2026 (large governments, 50,000+ population) or April 24, 2027 (small governments). Private businesses: case law under ADA Title III makes WCAG 2.1 Level AA the de facto standard.

No, not on their own. YouTube auto-captions are approximately 85–92% accurate on clean single-speaker English but drop to 60–75% on accented English, technical vocabulary, or noisy audio. WCAG expects synchronized captions of adequate quality — accuracy is an expectation, not just presence. Auto-captions are a starting point that must be reviewed and corrected by a human for compliance-grade output.

None for captioning specifically. WCAG 2.2 (October 2023) added no new caption success criteria. SC 1.2.2 (prerecorded, Level A) and SC 1.2.4 (live, Level AA) from WCAG 2.1 (June 2018) remain the operative rules. The DOJ Title II Final Rule (April 2024) adopts WCAG 2.1 Level AA as its baseline conformance target.

For US federal agencies, yes — under Section 508 (revised 2018) and general Section 504 obligations. For public web content of state/local governments after April 24, 2026 (large) or April 24, 2027 (small), yes — under the DOJ Title II Final Rule. For private businesses, WCAG 2.1 SC 1.2.4 (Level AA) is the de facto standard cited in ADA Title III lawsuits. For IP-delivered video that previously aired on US broadcast television, FCC Report and Order 11-36 (2012) requires live captions per the CVAA phase-in.

SRT for maximum compatibility (YouTube, video editors, most platforms). WebVTT (.vtt) for HTML5 web video with native browser support and CSS styling. DFXP/IMSC 1.2 for Netflix and broadcast-quality delivery with strict styling requirements. SCC (Scenarist Closed Captions, using EIA-608 codes) for US broadcast TV workflows.

WCAG 2.1 Success Criterion 1.2.2 (Level A) requires captions for prerecorded synchronized media — any recorded video with audio. Success Criterion 1.2.4 (Level AA) requires captions for live synchronized media — webinars, live streams, and real-time video. SC 1.2.4 is a stricter, higher-conformance-level requirement that many small organizations skip.

For accessibility compliance under ADA Title III (private businesses), best practice is yes for all published video. Instagram, TikTok, and LinkedIn each provide auto-caption features, but manual review is recommended for WCAG-compliance-grade output. Auto-captions typically achieve 85–92% accuracy on clean English audio and are not sufficient on their own to satisfy WCAG.

"Closed captions" (often shortened to CC) means on-screen text that reproduces spoken dialogue, speaker labels ("NARRATOR:", "WOMAN:"), and non-speech audio cues ([door closes], [applause], [music playing]) for viewers who cannot hear the audio. "Closed" means the captions can be turned on or off by the viewer — as opposed to "open captions" which are permanently burned into the video and always visible. On a remote, TV, or player, the CC button toggles closed captions on/off.

During playback: (1) click or tap the screen to show the player controls, (2) click the speech-bubble icon or select "Subtitles" from the menu, (3) choose "Off" from the list. On a TV app: press up or menu on your remote during playback, navigate to Subtitles/Audio, select Off. To set the default for your whole account: sign in on Netflix.com → Manage Profiles → pick a profile → Subtitle appearance → set language and style. Netflix uses IMSC 1.2 (DFXP) internally, but you never see the file — it's a viewer-side toggle.

On a Roku: press the star (*) button on the remote during playback → Closed Captioning → Off. Or from the home screen: Settings → Accessibility → Captions mode → Off. On most Smart TVs (Samsung, LG, Sony, TCL): press the CC button on the remote (sometimes labeled Subtitle), or open Settings → Accessibility → Captions and toggle off. Cable/satellite box: press the CC button on the remote, or navigate to Menu → Setup → Closed Captioning → Off. AMC and other cable channels rely on the box or TV setting, not per-channel controls.

Closed captions can be toggled on/off by the viewer — they're stored as a separate file (SRT/VTT/DFXP) that the player reads and overlays on the video. Open captions are burned directly into the video pixels — they're always visible and cannot be turned off. Open captions are used for viral social clips (TikTok, Reels, Shorts) where auto-play with muted audio is the norm, or for accessibility-first videos where you want to guarantee captions display regardless of player support. Closed captions are the standard for TV, streaming platforms, and web video where viewer choice matters.

SDH (Subtitles for the Deaf and Hard-of-Hearing) is a hybrid — the format of a subtitle file with the content of closed captions. It includes speaker labels and non-speech audio cues (like CC) but is delivered as a subtitle track (like translated subtitles). Netflix and other streaming platforms often list "English [CC]" and "English SDH" interchangeably. The distinction matters historically: traditional closed captions used EIA-608 or CEA-708 broadcast standards, while SDH uses subtitle file formats (SRT, VTT, DFXP). For accessibility compliance, both count as captions.

The standard CC icon is a rectangle containing the letters "CC" — usually black or gray. It's used across TV remotes, video players (YouTube, Netflix, Vimeo, VLC), and social apps to indicate that captions are available and can be toggled on/off. Some platforms use variants: a speech bubble icon (Netflix mobile), the letters "SUB" (in some international contexts), or a filled/outlined rectangle to indicate captions on/off state. The Unicode character for the closed captions symbol is U+1F5A9 (🖩) but most platforms use custom SVG icons instead.

EU: Yes. The European Accessibility Act (Directive 2019/882) took effect June 28, 2025 and requires captions for audiovisual media services and digital products including e-books, e-commerce, and banking apps. Compliance is by June 28, 2025 for new products; existing products have until June 28, 2030. Brazil: Yes. The Lei Brasileira de Inclusão (LBI, Lei 13.146/2015) requires accessibility including subtitles and audio description for broadcast television and digital public services. WCAG 2.1 AA is the de facto standard, with enforcement through the Ministério Público and civil-society advocacy. Federal government services must comply per Decreto 5.296/2004 and the eMAG accessibility guidelines.