Apple Books not syncing PDFs between devices

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Level 1

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Apple Books not syncing PDFs between devices

I want to sync PDFs between my iPad mini (26) and Mac (Tahoe 26.3). On either device, when I upload a PDF, it won't show up on the other device. I've tried everything (that I know of).

Both devices are using the same account.
The PDFs are kept in iCloud Drive and sync fine there.
Books from the store sync fine.
iCloud is on for Books on both devices -- tried turning it off, restarting the devices, and turning it back on again.
Sync is on in Books settings on both devices, tried turning that on and off again too.
Tried creating and uploading a fresh PDF to see if it was an issue with the files. Still didn't sync.
Even tried rebuilding the library and group containers, and clearing caches, no help.
The PDF added on the iPad is present in ~/Library/Mobile Documents/iCloud~com~apple~iBooks but won't show up in the actual Books app.

I think this is a bug, but I just want to check if anyone has any other ideas to try?

MacBook Air 13″, macOS 26.3

Posted on Jul 6, 2026 6:38 PM

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Answer 1

Top-ranking reply

v1v3km

Level 5

6,124 points

Jul 6, 2026 11:10 PM in response to suz248

You've done excellent troubleshooting. Given that the PDF appears in ~/Library/Mobile Documents/iCloud~com~apple~iBooks but not in Books app itself, this is almost certainly a known sync issue with Books in macOS/iPadOS 26 (specifically how Books reads from its iCloud container). Here are some additional things to try:

1. Force Books to re-index its library

On Mac:

- Quit Books completely

- Open Terminal and run: killall bird (this restarts the iCloud sync daemon)

- Relaunch Books and wait a few minutes

2. Check Books library database

- On Mac, go to ~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks/Books/

- Check if the PDFs appear here (this is Books' internal library folder, separate from iCloud)

- If not present, Books may not be picking them up from the iCloud container

3. Try adding via Books drag-and-drop on Mac

- Open Books on Mac

- Drag the PDF file directly onto the Books window

- Check if it now syncs to iPad

4. Check PDF file format compatibility

- Some PDFs (especially heavily encrypted or non-standard format) won't sync properly

- Try with a simple, basic PDF to confirm if it's a file issue

5. Sign out of iCloud on one device and sign back in

- On the Mac: System Settings > Apple ID > Sign Out > Sign Back In

- This refreshes the iCloud Books sync token

6. This does appear to be a macOS/iPadOS 26 Books bug

Given your detailed testing, I'd recommend submitting feedback via https://feedbackassistant.apple.com as this is likely a regression in the new OS version that needs an Apple fix.

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