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How to sign a PDF or document on an iPhone

Checked 4 October 2026

To sign a PDF on an iPhone, open it from Mail or Files and tap the Markup button. Tap the Add button, then Add Signature. Sign with your finger, tap Done and drag the signature into place. Your iPhone saves it for next time. Recent versions of iOS also include a Preview app that does the same.

An iPhone is the best device for signing a PDF, because you sign with a finger on glass rather than dragging a mouse. Apple builds this in: you can fill out and sign PDF forms on iPhone, and Markup lets you create signatures and reuse them.

Here is Apple's route first, then where a browser tool helps.

Step by step

  1. 1Save the PDF to FilesFrom Mail or Messages, tap the attachment, then share it to the Files app so you have a copy to work on.
  2. 2Open it and fill in any fieldsTap a field and type. AutoFill can offer details saved on your iPhone.
  3. 3Open MarkupTap the Markup button, then the add button, then Add Signature.
  4. 4Sign with your fingerSign on the line. Tap Clear and sign again if you are not happy. Signatures you create are saved for reuse in supported apps.
  5. 5Place, resize and shareDrag the signature into position and pinch to resize, then share the finished document back by email.

What Markup can't do

  • Markup draws on top: nothing is flattened, so your signature stays a movable annotation.
  • Typing onto a flat form means adding a text box by hand for every answer.
  • No tick or date fields, and no way to produce a Word version.
  • Signatures are tied to your iPhone rather than available in a browser on any device.

Finish it here instead

Type onto the page, tick the boxes, add the date and a signature you can reuse, then save a flattened PDF. It runs in this browser — your file is not uploaded.

or drop a file here · nothing is uploaded

Questions

Can I sign a PDF on an iPhone without an app?
Yes. Markup is built into iOS, and PDFpad works in Safari on the same phone if you need typed fields, ticks, dates or a flattened result.
Why does my signature look better on a phone?
Because you draw it with a finger at something close to writing speed. A mouse or trackpad produces the wobble everyone recognises.
Should I sign in Mail or in the Files app?
Mail is quickest for a one-off. Tap the attachment, tap Markup and sign. Then tap Done and choose to reply to the sender. Files is better if you want to keep a copy or fill in fields first. Both use the signatures your iPhone has saved.
How do I sign a PDF in the Preview app on iPhone?
Open the PDF in Preview and tap the Form Filling button. Tap each field to fill it in. Then tap the Add button to add your signature or a text box.
How do I add initials or delete a signature on iPhone?
In Markup, tap the Add button, then Add Signature, then Add or Remove Signature. Tap the Add button to create another, such as your initials. Tap the Delete button next to one to remove it.

Sources

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