Prevent errors

Rule ID	Error 4
Conformance	Required
Definition	To prevent errors when input includes legal and/or financial transactions (e.g. online shopping, banking), the user must be able to either reverse, check or confirm the data before the transaction is finalized.
Purpose	The intent of this rule is to help users with disabilities avoid serious consequences as the result of a mistake when performing an action that cannot be reversed. For example, purchasing non-refundable airline tickets or submitting an order to purchase stock in a brokerage account are financial transactions with serious consequences.
Conformance	Required
WCAG Success Criteria	Success Criterion 3.3.4 Error Prevention (Legal, Financial, Data) Other Related Success Criterion:
Rule Category	Forms
Rule Scope	Page
First Step	no
Techniques	Provide a confirmation page showing all the user inputs before for final submission of the information for modification of user controlled data on a server. Provide a means for the user to review previous submissions and give them the ability to cancel or modify previous submissions of legal or financial information. Use a confirmation checkbox in addition to the submit button, to require the user to confirm the data is valid before submission.
Information Links	Understanding SC 3.3.4 Error Prevention (Legal, Financial, Data.) G164: Providing a stated time within which an online request (or transaction) may be amended or canceled by the user after making the request. G98: Providing the ability for the user to review and correct answers before submitting. G155: Providing a checkbox in addition to a submit button. G99: Providing the ability to recover deleted information. G168: Requesting confirmation to continue with selected action. G155: Providing a checkbox in addition to a submit button. G98: Providing the ability for the user to review and correct answers before submitting. G168: Requesting confirmation to continue with selected action.