A team chat tool is accessible only if people can reach conversations, understand new activity, compose and correct messages, share files, join calls, control notifications, and recover from errors with the input and output methods they use. A vendor accessibility page is useful evidence, but it is not a substitute for testing the exact plan, platform, configuration, integrations, and workflows your team depends on.
Build a representative test matrix
List the desktop, web, mobile, and assistive-technology combinations actually in scope. Include keyboard-only navigation, at least one screen reader used by the team, browser zoom, high-contrast or forced-colors mode where applicable, speech input, reduced motion, and caption needs. Record app version, operating system, browser, workspace settings, and date.
Create a private test workspace with invented content. Include public and private channels, direct messages, threads, reactions, mentions, search, file sharing, images, code snippets, an audio or video meeting, and a notification burst. Avoid putting real confidential messages into evaluation recordings or screenshots.
Complete core chat tasks without a pointer
Starting from launch or sign-in, use only the keyboard to switch workspaces, find a channel, move through unread messages, open a thread, compose and edit a message, attach a file, add image description text, react, search, change status, and adjust notification preferences. Focus should remain visible, follow a logical order, and return predictably when dialogs close.
The WCAG 2.2 understanding documents cover keyboard access, focus, color, captions, target size, names and roles, and status messages. Use those criteria to organize evidence, while recognizing that a native application may use platform accessibility conventions rather than browser markup.
Listen to the conversation with a screen reader
Check whether the screen reader announces channel names, sender, timestamp, message text, reactions, thread state, edit state, unread position, attachments, and presence without drowning the user in repetition. Test navigation by message and by region. New messages should be discoverable, but assertive announcements should not continually interrupt reading or composing.
Vendor guidance can reveal intended commands. Slack's accessibility documentation describes keyboard navigation, screen-reader support, display controls, captions, transcripts, image descriptions, and announcement preferences. Microsoft likewise documents core Teams tasks with a screen reader. Verify those documented paths in the selected product rather than assuming they work identically across versions.
Inspect visual presentation and non-text cues
Increase zoom and text size, narrow the window, enable a high-contrast theme, and check that the composer, message actions, threads, search results, and settings remain usable. Color must not be the only signal for unread, presence, errors, selected channels, or mention priority. Custom emoji, animated images, and moving reactions need controls that respect motion preferences and do not flash dangerously.
Images need meaningful descriptions when they convey information. Link text should remain understandable. Tables, code blocks, polls, and third-party app cards require their own review because structured content can collapse into an incoherent reading order.
Test notifications, audio, video, and alternatives
Check visual, audible, and screen-reader notifications separately. Users should be able to reduce nonessential interruptions while keeping direct messages, urgent calls, or chosen channels discoverable. Test quiet hours, mobile handoff, multiple workspaces, focus mode, and notification history. A sound-only incoming-call signal needs a visual or assistive alternative; a badge-only signal needs a nonvisual route.
For meetings or huddles, test keyboard entry and exit, mute and camera controls, live captions, transcript availability, chat, reactions, screen sharing, interpreter visibility where relevant, and control of caption presentation. Record language and accuracy limitations honestly. Do not treat automatic captions as perfect or claim accessibility for every participant from one successful call.
Include administration, integrations, and recovery
Ask a keyboard and screen-reader user to create a channel, manage membership, review permissions, find retention settings, export permitted data, and recover a deleted or mistaken action where supported. Test sign-in, multi-factor authentication, password recovery, session expiry, and account switching. Bots, forms, calendars, and ticket integrations can introduce inaccessible dialogs or messages even when the core chat is usable.
Record failures with task, steps, expected result, observed result, platform, severity, evidence, workaround, owner, and retest date. Separate a verified workaround from a fix. Ask disabled users who perform the real work to review high-impact flows, compensate them appropriately, and avoid turning one person's result into a universal claim.
The decision record should state which combinations passed, which remain blocked, what accommodations or alternative channels are needed, and when the tool will be retested. That bounded conclusion is more credible than a single score: this team can complete these named tasks on these tested configurations, while these documented limitations still require action.
Sources
- Understanding WCAG 2.2 — W3C Web Accessibility Initiative
- Accessibility in Slack — Slack Help Center
- Quick Start Guide: Using Microsoft Teams with a screen reader — Microsoft Support