Where to start with InDesign Accessibility | Threading and Beyond

Today’s blog post grew out of a conversation with Colleen Gratzer about InDesign accessibility and how to create accessible PDFs.

One of the biggest takeaways is that accessible PDFs start with accessible source documents, which means building structure, reading order, paragraph styles, and tagging into the InDesign file before export.

This post is an outtake from my podcast episode with Colleen, where we focused on why designers should incorporate accessibility best practices during the production phase rather than as a last-minute fix at the end.

Video Guide

Build a Strong Foundation with Paragraph Styles

Paragraph styles play the biggest role in creating accessible documents in InDesign. They do much more than control appearance. They define the structure that assistive technologies use to interpret the document.

A well-structured document uses paragraph styles consistently for:

Headings
Body text
Lists
Table headings

When designers apply manual formatting instead of paragraph styles, screen readers cannot recognize headings or understand the document hierarchy. Paragraph styles also make it much easier to update documents and generate tables of contents.

Many accessibility challenges disappear when designers use InDesign as it was designed to be used.

Use Threaded Text Frames to Create Logical Reading Order

Threading connects separate text frames into one continuous story. This feature becomes especially important when text flows across multiple columns or pages.

For example, a news article might include a section heading, headline, subheading, and body copy placed in separate text frames. Threading those frames tells assistive technologies that the content belongs together and should be read in sequence.

The same principle applies when text continues from one page to the next. Threading preserves the natural reading order so readers experience the content as one uninterrupted story.

Export Settings Matter

Even a carefully prepared document can lose its accessibility if you export it incorrectly.

When exporting from InDesign to Acrobat, use these settings:

Export as Pages
Enable Create Tagged PDF
Enable Use Structure for Tab Order

The first two settings are essential. If you forget to enable Structure for Tab Order, Acrobat provides a way to correct it later.

NOTE: Some projects include high-resolution images but also need to meet strict PDF file size limits. In these cases, adjust image compression settings during export.

Run automated and manual accessibility check

After exporting to PDF, Acrobat’s Accessibility Checker provides a useful starting point. It identifies common issues and helps verify that accessibility information was transferred successfully.

Next, do a manual review for items such as:

Reading order
Color contrast
Heading structure
Alternate text
Appropriate use of tags

Human review remains an essential part of the process.

After completing these reviews, run the PDF through the PAC tool for final additional validation.

A Practical Accessibility Workflow

A consistent workflow makes accessibility easier to manage throughout a project.

Review the document structure.
Apply paragraph styles consistently.
Build a logical heading hierarchy.
Thread related text frames.
Use native tables and built-in table of contents features.
Add alternative text where needed.
Export a tagged PDF using the correct settings.
Review the PDF in Acrobat.
Complete a manual accessibility check.
Run a final accessibility check in the PAC tool to validate PDF/UA compliance and identify any additional issues.

Building accessibility into your InDesign documents from the beginning creates better PDFs, reduces remediation work, and delivers a more usable experience for everyone who reads your content.

Let me be your champion for inclusion. I offer tailored solutions (and self-paced courses!) to ensure your documents meet and exceed compliance expectations. For more detailed insights, tutorials, and in-depth discussions on accessibility and related topics, don’t forget to check out my YouTube channel: The Accessibility Guy on YouTube. Subscribe for regular updates!