How to open .PUB files on iOS
To open .PUB files on iOS, iOS typically won’t open .PUB with full fidelity; share or transfer the file to a Windows PC and open it with Microsoft Publisher.
Step-by-step instructions
- iOS typically won’t open .PUB with full fidelity; share or transfer the file to a Windows PC and open it with Microsoft Publisher.
Common issues
The .PUB file won’t open or shows as an unknown format
This usually happens when Microsoft Publisher (or a compatible importer) isn’t installed on the device, or the OS has no associated app for .PUB.
- On Windows, install Microsoft Publisher and open the file from within Publisher (File > Open).
- On non-Windows devices, move the file to a Windows PC with Publisher for the most reliable results.
Layout/formatting changes after opening in another app
Because .PUB is proprietary, importers may not fully support all layout features, fonts, or embedded objects.
- Open the file in Microsoft Publisher to preserve layout and typography as authored.
- If you must use an importer, compare the output carefully (especially text reflow, image placement, and missing fonts).
A tool identifies the file as application/x-mspublisher but your workflow expects another MIME type
Some systems detect .PUB as application/x-mspublisher; assuming an IANA-registered type may cause handling issues in strict pipelines.
- If you control the pipeline, allow application/x-mspublisher for Publisher content where appropriate.
- If you need broader compatibility, open in Publisher and export to a more widely supported format used by your workflow.
Security note
.PUB is a complex, proprietary format; treat files from unknown sources as potentially risky because document parsers can have vulnerabilities.