Accessible e-books between EPUB 3 and PDF/UA

Not legal advice. Whether and how far your publishing or distribution business is affected should be clarified case by case.

What the directive covers

Article 2(2)(e) of Directive (EU) 2019/882 names "e-books and dedicated software". Article 3 defines this as a service: the provision of digital files conveying an electronic version of a book that can be accessed, navigated, read and used, together with the software and apps dedicated to exactly that. E-readers form a separate product category. According to recital 41, publishers and other economic operators involved in distribution can also count as service providers.

Annex I Section IV(f) describes what an accessible e-book has to achieve, without prescribing technology:

• synchronised text and audio where an e-book contains audio in addition to text,
• e-book files must not prevent assistive technology from operating properly,
• access to the content, navigation of the content and layout including dynamic layout, provision of structure, and flexibility and choice in how content is presented,
• alternative renditions of the content and interoperability with a variety of assistive technologies,
• discoverability through metadata about accessibility features,
• digital rights management (DRM) must not block accessibility features.

For the wider legal framework, see The European Accessibility Act and PDFs, BaFG in Austria and BFSG in Germany.

EPUB for flowing text, PDF for fixed layout

For fiction and most non-fiction, EPUB 3 with the W3C Recommendation EPUB Accessibility 1.1 has become the industry standard. EPUB is based on HTML and reflows. Readers choose font size, spacing and colours themselves, and screen readers and read-aloud features handle it well. The directive asks for "flexibility in presentation" and "dynamic layout". A well-made EPUB delivers both almost by default; a PDF only with effort.

There are still good reasons for PDF. Textbooks with complex figures, academic publications, standards, art books and titles cited by page number depend on their layout. A PDF properly tagged to PDF/UA can be accessible. Readers who need strong magnification or their own colours still run into the limits of fixed pages, though. Many publishers therefore offer EPUB as the primary accessible edition and PDF alongside it.

Metadata decides whether anyone finds the book

An accessible e-book is of little use if nobody can find it as one. That is why the EAA explicitly requires metadata about accessibility features. It is maintained in two places.

Inside the EPUB file, EPUB Accessibility 1.1 requires the schema.org properties accessMode, accessibilityFeature and accessibilityHazard; accessibilitySummary and accessModeSufficient are recommended. The conformance statement, such as "EPUB Accessibility 1.1 - WCAG 2.2 Level AA", goes in dcterms:conformsTo.

Retailers and platforms receive the information via ONIX, specifically code list 196 (used with ProductFormFeatureType 09). It has codes for conformance, for individual features such as table-of-contents navigation or alternative text, for hazard warnings, and dedicated codes for the EAA exemptions.

The information has to be accurate. A title labelled "accessible" whose figures lack alternative text does more harm than an honest statement of its limitations.

The real work happens in typesetting

Quality depends on the editorial work on the content. That work is the same for EPUB and PDF.

Reading order and navigation

Marginal notes, info boxes and captions belong where they make sense in the content, not wherever they happened to be placed in the layout software. Running heads and page numbers are artifacts in a PDF. Longer works need a linked table of contents, and PDFs need bookmarks as well. If the print edition is cited by page number, the e-book should carry those page numbers, in EPUB through a page list.

Footnotes and formulas

Reference markers and note text must be linked. PDF/UA uses the Note tag for this, PDF/UA-2 uses FENote; EPUB uses references with back links. Formulas as images are silent for screen readers. In EPUB, MathML is the recommended approach. In PDF/UA-1 every formula needs a Formula tag with alternative text, and PDF/UA-2 also allows MathML.

Figures and language

Informative figures need alternative text, complex diagrams an extended description as well. In textbooks this is editorial work that has to be in the production schedule, or it will be missing on publication day. The main language is set, and foreign-language quotations are marked up separately so that speech output pronounces them correctly.

Which of these points can be checked automatically is listed in the accessible PDF checklist.

Older titles and the backlist

You will often hear that older e-books are exempt anyway. The directive does not support that as a blanket statement. The exemptions in Article 2(4) explicitly concern content of websites and mobile applications, such as office file formats published before 28 June 2025 or archived content not updated after that date. They contain no general exemption for e-books sold as a service in their own right.

The EAA applies to services provided after 28 June 2025. How backlist titles that are still sold after that date should be treated is seen differently within the industry and by national authorities. You need a legal assessment for your own case here.

Anyone relying on a disproportionate burden must assess and document it under Article 14, keep the records for five years and, for services, renew the assessment at least every five years. Microenterprises providing services are exempt under Article 4(5).

We recommend producing all new titles accessibly and working through the backlist by importance and sales.

EasyPDFUA and PDF editions

EasyPDFUA works with PDF only, not EPUB. The PDF/UA check quickly shows whether a PDF title is tagged at all and whether title, language, fonts and Unicode mappings are correct; for large catalogues the same stocktake runs through the API. For untagged backlist PDFs, retroactive tagging adds a base structure, title, language and link tags. It does not reconstruct headings, footnotes, formulas, tables or alternative text, which is exactly the main work in an academic book. That work belongs in typesetting and production. Other sectors are listed in the overview of affected industries.

Frequently asked questions

Do e-books have to be accessible since 2025?

Yes, if they are offered to consumers as a service after 28 June 2025. The EAA covers e-books and dedicated software. Microenterprises providing services are exempt. The details are set out in national laws such as the Austrian BaFG and the German BFSG.

Is EPUB or PDF better for accessible e-books?

For most books, EPUB 3 with EPUB Accessibility 1.1, because the text reflows and adapts to the reader. PDF to PDF/UA is common for layout-bound academic and educational titles and can be accessible too, but it is less flexible.

Which accessibility metadata does an e-book need?

In EPUB, the schema.org properties accessMode, accessibilityFeature and accessibilityHazard, which EPUB Accessibility 1.1 requires, plus the recommended accessibilitySummary and accessModeSufficient. Retailers receive the information via ONIX code list 196.

Are older e-books exempt from the requirements?

Not across the board. The exemptions in Article 2(4) of the directive concern content of websites and apps, not e-books as a service in their own right. How backlist titles should be treated is viewed differently across the industry and needs a legal assessment for your case.