You can sign a PDF on an iPhone or Mac without printing it. On iPhone, open the PDF in Preview and use Markup or the signature control. On Mac, use Preview’s Markup toolbar to create a signature with your trackpad, camera, or nearby Apple device. These steps add a visible signature; use a certificate workflow if the recipient specifically requires a certificate-based digital signature.

Apple updates its interface over time. The steps below follow Apple’s current iPhone PDF guide and Preview for Mac guide.

When you want the same workflow in Chrome

If you also work on a computer with Chrome, Sign PDF Document gives you one place to finish a PDF: draw or upload a signature, add typed text, dates, stamps, and notes, then place and rotate every item. It can also merge PDFs and images, manage page order, and export or print the result. Files are processed locally in the browser and no account is required.

This is useful when the recipient accepts a visible electronic signature. It does not provide the certificate or digital ID required for certificate-based signatures.

Sign a PDF on iPhone

  1. Save or open the PDF in the Files app, or open it in Preview if available on your iOS version. You can also use the PDF viewer in a compatible app.
  2. Tap the PDF to open it. If it is a form, tap a field and enter the requested information before signing.
  3. Open Markup or the annotation controls. Depending on the app and iOS version, tap Add and choose Add Signature, or select the signature tool from the markup menu.
  4. Draw your signature with your finger, or select a saved signature if the app offers one. Tap Done.
  5. Drag the signature onto the correct line. Use the handles to resize it, and make sure it does not cover nearby text or a date field.
  6. Save or export the PDF. If you are sharing from the preview, choose a destination that creates the signed file rather than replacing your only original.
  7. Open the saved copy again from Files and check every page.

If the PDF is an interactive form, use its form-filling controls first. A blank line in a non-interactive document may require an annotation rather than a form-field signature. The available buttons can vary depending on where the PDF is open.

Sign a PDF on Mac with Preview

  1. In Finder, open the PDF with Preview. If another app opens it, Control-click the file and choose Open With → Preview.
  2. Select the Markup button to show the markup toolbar, then select Sign.
  3. Create a signature using one of the offered methods:
    • Trackpad: write your name with a finger, then confirm.
    • Camera: sign on white paper and hold it up to the camera as directed.
    • iPhone or iPad: select a nearby device and sign on its screen if Continuity is available and the devices meet Apple’s requirements.
  4. Select the saved signature and click where it belongs in the PDF.
  5. Drag the signature into position and resize it with the handles. Review the page at normal zoom.
  6. Choose File → Save or export a separate copy. Keep an untouched original when you need a record of the unsigned document.
  7. Close and reopen the signed copy. Confirm that the mark is present and all pages remain in order.

Saved signatures may be available to other apps or devices connected to your Apple setup. If you are using a shared Mac, review where the signature is stored and remove saved marks you no longer want to keep.

iPhone vs Mac: which should you use?

SituationiPhoneMac
You need to sign a short form on the goConvenient for a quick markupWorks, but requires access to the computer and file
You need precise placement or a long documentPossible, but small fields can be harder to positionLarger screen makes review and placement easier
You want to create a saved signatureDraw with a finger where supportedUse trackpad, camera, or nearby iPhone/iPad
The PDF has many pages or detailed fieldsZoom and check every page carefullyEasier to compare pages and inspect fields
A certificate-based signature is requiredUse the named certificate app or workflowUse the organization-approved certificate workflow

Fix common issues

  • I cannot find Preview on iPhone: app availability and labels depend on the iOS version. Open the file in Files or the app that received it and look for Markup or signature annotations.
  • The signature tool is missing: the PDF viewer may not support signatures, or the file may restrict editing. Open it in Preview or another approved editor; ask the sender for help if it is protected.
  • The signature is too large or small: select it and use the resize handles before saving. Reopen the exported copy to confirm the change stuck.
  • My form fields do not work: the PDF may not contain interactive form fields. Use text annotations only if the recipient accepts them, or request a fillable version.
  • Someone else needs to sign next: do not edit a certificate-signed file without permission. Ask the sender how to route the document for sequential signing.

Before you send the PDF

Check that you are sending the correct copy to the intended recipient. Review the signature placement, date, initials, and all required fields. Open the saved file after export; a preview that looked right before saving is not proof that the downloaded copy is complete. For sensitive documents, use the recipient’s approved channel.

Official references