PDFs are still the default format for reports, invoices, forms, and whitepapers. Yet for millions of screen-reader users, opening a PDF can feel like opening a locked box. The document looks fine visually, but the assistive technology underneath reads content in the wrong order, skips images, or announces page headers as body text.
The good news: most PDF accessibility failures fall into six predictable categories. Fix these and your documents become usable for blind and low-vision readers, easier for search engines to parse, and more defensible under ADA, Section 508, and the European Accessibility Act.
1. Missing tags — the document has no structure
A PDF without tags is just a canvas of text and images. Screen readers see an undifferentiated stream of characters because there are no headings, paragraphs, lists, or landmarks to navigate by.
How to fix it: Generate tagged PDFs from the source file (Word, InDesign, Google Docs) using export options like "Document structure tags for accessibility." If the PDF is already untagged, run auto-tagging in Adobe Acrobat or a tool like EasyAccessPDF, then verify the tag tree.
2. Broken reading order — content jumps around
Multi-column layouts, sidebars, and floating text boxes often cause screen readers to read across columns instead of down them. A sentence from the left column can be followed by a sentence from the right column mid-paragraph.
How to fix it: Use the Reading Order tool in Acrobat to number content in the intended sequence. Listen to the document with NVDA or JAWS to catch jumps that automated checkers miss.
3. Missing or poor alt text — images become silence
Charts, diagrams, and screenshots without alternate text are skipped entirely. Decorative images that are tagged waste time because the screen reader announces them as content.
How to fix it: Mark decorative images as artifacts. Write descriptive alt text for meaningful images, and for charts, describe the insight rather than the appearance.
4. Inaccessible tables — data without context
When table header cells are tagged as regular data cells, screen-reader users hear numbers without knowing what they represent. Merged cells and nested tables make the problem worse.
How to fix it: Use proper TH tags with scope attributes. Avoid merged cells in source documents and verify table navigation with a screen reader.
5. Missing language declaration — mispronounced words
Without a document language set, a screen reader may try to read English text with a French voice, or vice versa. Every word becomes harder to understand.
How to fix it: Set the document language in File > Properties > Advanced. For multilingual PDFs, add span-level language attributes where the language switches.
6. Nondescriptive links — "click here" everywhere
Users browsing by link list encounter dozens of identical "read more" or "click here" entries. They must read surrounding context for every link.
How to fix it: Use meaningful anchor text at the authoring stage: "Download the 2025 accessibility report" instead of "Click here."
Validate before you publish
Automated checkers catch missing tags and alt text, but they cannot judge reading order or semantic accuracy. Test with a real screen reader, or use a validator like PAC 2024 or EasyAccessPDF's free PDF checker, which audits against PDF/UA and WCAG principles.
Making PDFs accessible is not just about compliance. It is about ensuring that everyone who needs your information can actually use it.