# How to sign a PDF on an iPhone

Open the PDF in the Files app, tap the Markup button, tap the plus button, choose Add Signature, and sign with your finger. It's built into iOS and iPadOS and costs nothing.

## Steps in the Files app

1. Get the PDF into Files. If it came by email, tap the attachment, tap the Share button, and choose Save to Files.
2. Open the Files app and tap the PDF.
3. Tap the Markup button. It looks like a pen tip in a circle.
4. Tap the plus button, then Add Signature.
5. Sign with your finger, or an Apple Pencil on an iPad, and tap Done. Your iPhone saves it for next time.
6. Drag the signature onto the line. Pull the blue dots to resize it.
7. Tap Done. Files saves the signed PDF in place.

Then send it back from the Share button, or attach it to a reply in Mail.

## Signing straight from Mail

You can skip Files. In Mail, tap the PDF attachment, tap Markup, and add your signature the same way. When you tap Done, Mail offers to reply with the signed file attached. That's the fastest route for a form someone emailed you.

## The Preview app

Newer versions of iOS and iPadOS also include a Preview app for PDFs. It has a Form Filling button for typing into fields, and the same plus button to add your signature. Use whichever you have. Apple's [iPhone signing guide](https://support.apple.com/guide/iphone/fill-forms-sign-documents-create-signatures-iph1d3607e5c/ios) matches the current version.

## Tips for a cleaner signature

- Turn the phone sideways before you sign. You get a wider box and a steadier line.
- Sign slower than you would on paper.
- Save initials as a second signature for forms that ask for them on every page.

## When Markup isn't enough

Markup puts an image of your signature on the page. It doesn't record when you signed or stop the file being edited later. If you're the one collecting signatures, send the PDF through an e-signature service. Each person signs from their own phone through a link. See [how to sign a PDF](/guides/how-to-sign-a-pdf) for when that's worth it, or the [Android steps](/guides/how-to-sign-a-pdf-on-android) for a signer on another phone.

## Common questions

### Why don't I see the Markup button?

Some apps show the PDF without editing tools. Save it to Files first and open it there, where Markup is always available.

### Can I delete a signature I saved on my iPhone?

Yes. Tap the plus button in Markup, then Add Signature, and remove the one you don't want from the list of saved signatures.

### Can I sign a PDF on an iPhone without downloading an app?

Yes. Markup is part of iOS and iPadOS, in Files, Mail and Photos. You don't need anything from the App Store.