Short answer
As of iOS 18 / iOS 26, there is no native iOS feature to add a password or Face ID lock to an individual PDF file in the Files app — Apple's Files app does not expose per-file encryption. A practical built-in workaround: save the PDF into a Note in the Notes app, then lock that note (tap ··· → Lock Note) using Face ID or device passcode; this hides the PDF within a Face ID-protected note, though the PDF file itself outside Notes remains unprotected. True file-level PDF password encryption — the kind that travels with the file and asks for a password in any viewer — requires a third-party app; many dedicated scanner and PDF apps offer this, plus an in-app Face ID vault that locks all stored documents behind biometric authentication.
ScanTo Pro does this on your iPhone: it scans to a clean PDF, runs on-device OCR, and can lock files with Face ID — a pay-once app with no subscription. Check the App Store listing for current features.
What to look for before choosing
- iOS has no native per-file PDF password feature in the Files app (as of iOS 18/26)
- Notes app workaround: embed PDF in a locked Note — protects it within Notes via Face ID, but not the file itself
- Third-party apps can add AES-256 password encryption directly into the PDF file (portable protection)
- In-app Face ID vaults (common in dedicated scanner apps) lock all stored documents behind biometrics
- A file-level password is portable — it travels with the PDF and is enforced in any compliant viewer on any platform
A practical decision process
- iOS has no native per-file PDF password feature in the Files app (as of iOS 18/26).
- Notes app workaround: embed PDF in a locked Note — protects it within Notes via Face ID, but not the file itself.
- Third-party apps can add AES-256 password encryption directly into the PDF file (portable protection).
- In-app Face ID vaults (common in dedicated scanner apps) lock all stored documents behind biometrics.
- A file-level password is portable — it travels with the PDF and is enforced in any compliant viewer on any platform.
Quick comparison
| Need | What to check | Why it matters |
|---|---|---|
| Pricing model | Check whether useful features require a subscription, a one-time unlock, or neither. | The cheapest app on day one may not be cheapest after a year. |
| Privacy model | Prefer on-device work when the content is sensitive. | Private documents, resumes, study data, and family content deserve careful handling. |
| Export / lock-in | Confirm file formats, sharing, backup, and deletion controls. | A good app should help you finish the task, not trap your work. |
Where ScanTo Pro fits
ScanTo Pro is a strong fit when you want private, on-device scanning without a subscription.
Pay onceNo subscriptionOn-device
This page is an independent buying guide. App Store features and prices can change, so confirm details on the listing before purchase.