WCAG 3.3.6 Error Prevention (All): What It Means and How to Test It

Anton StewartAuthor Reviewed September 28, 2026 against the W3C Understanding document

What WCAG 3.3.6 Requires

AAA only: the review, correction and confirmation requirements of 3.3.4 apply to every form submission, not only legal, financial or data-deletion ones.

Can AccessBell Test This Automatically?

Not fully. Like most WCAG criteria that depend on meaning or context, this one needs a person to judge. AccessBell's report lists it for manual review rather than marking it pass or fail automatically, so it never gets missed.

How to Test It by Hand

Check that every form on the site, not just high-stakes ones, offers a way to review and correct input before submitting.

Common Failures

A simple contact form submits immediately with no review step, which is fine at AA but fails the broader AAA requirement.

WCAG 3.3.6 Questions

What does WCAG 3.3.6 require?

AAA only: the review, correction and confirmation requirements of 3.3.4 apply to every form submission, not only legal, financial or data-deletion ones.

Can AccessBell test WCAG 3.3.6 automatically?

Not fully. This criterion needs a person to judge, so AccessBell's report lists it for manual review rather than marking it pass or fail on its own.

What level is WCAG 3.3.6?

Level AAA, added in WCAG 2.0. Level AAA is the highest, most demanding conformance level in WCAG.

Sources

This page explains a technical standard and is not legal advice. See our disclaimer.

3.3.6 Error Prevention (All)