The purpose of the list element is to group related information items together on a webpage in a way that enhances user understanding.
Use of the list element does not generally impede accessibility to users with a disability — as long as the element is used correctly and with proper semantic markup. For example, when information is formatted as a list, it is essential for accessibility that the relationship between the list items is made explicit.
You can mark up list items using the
<li> element, but this tells screen readers nothing about the entire list. For that purpose, it is necessary to mark up the list as an ordered list, an unordered list or a definitions list, using
Guideline 1.3.1 Info and relationships defines the accessibility of lists as:
Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A)
This section applies not only to lists, but also to tables, PDFs and other ways of presenting information on a webpage.
Even when lists are used correctly, there are steps that can be taken to increase their accessibility.
In good web writing, lists are used for readability; grouping related information into lists not only makes information more readable for sighted users, but also navigable by a screen reader.
Screen readers treat lists as a single element so users can use keyboard shortcuts to get to the list (or lists if there's more than one list on a webpage) and jump from one list to another. The screen reader also announces the number of list items on a list. When a user wants to bypass a block of content like a list, they can do so because the screen reader treats the list as a single element.
Correctly marking up the list element allows screen reader users to navigate through each list item or to skip to, or past that list. A short and succinct list makes information easier to see but also easier for screen readers to navigate.