Sign PDFs in Preview — no printer or scanner needed

Print a document, sign it with a pen, scan it back into a PDF, and email it off — that ritual belongs to the past. Yet plenty of people still repeat it every single time, because they have no idea the Mac has a solution built in, for free. The Preview app, preinstalled on every Mac, can save your signature once and, from then on, drop it into any PDF in two clicks, with no printer, scanner, or extra app required.

A typical scenario

A contract arrives by email asking for a quick signature and return. Without Preview, that means finding a printer, printing it out, signing it with a pen, tracking down a scanner or at least taking a decent photo with your phone, and uploading it back to your computer — twenty minutes of searching and waiting, easily.

With a signature already saved in Preview, you open the document, click the signature icon, drag it into the right spot, and send the contract back in under a minute. On top of that, you get back to the client the same day, which for smaller vendor contracts often decides whether you land the job or someone faster does.

How to do it

1. Open the contract PDF in Preview.
2. Click the marker-pen icon in the menu bar (Show Markup Toolbar) to bring up the annotation panel.
3. Click the signature icon and choose Create Signature.
4. Sign either with your finger on the trackpad, or sign a regular pen-and-paper signature on white paper and hold it up to the Mac's built-in camera — Preview recognizes and crops the signature automatically.
5. The signature is saved to your signature library; next time, just pick it from the list and drag it onto the spot you need.
6. You can resize or rotate the signature by dragging its corners so it fits precisely on the signature line.
7. Save the document with Cmd + S and send it right back from your email.
8. Besides your signature, you can save a custom stamp or your initials the same way, if contracts require initialing on every page.

The best tools

• Built-in Preview with a signature saved once and for all — free, works offline, no sign-up required.
• Signing right inside Mail — you can open and sign a PDF attachment directly in a new-message window, without switching apps.
• DocuSign or Adobe Acrobat Sign — for contracts where the other side needs a verifiable electronic signature with a timestamp and audit trail, not just a visual imprint.
• iPhone or iPad with Apple Pencil for a cleaner signature — if your finger-drawn signature on the trackpad doesn't look tidy enough, you can create it on a connected iOS device instead.
• A pen-on-paper signature captured by the camera — for those who prefer their classic pen signature over a digital drawing, it's the most faithful way to bring it into a PDF.

What you get out of it

• Time: the print-sign-scan-send ritual shrinks down to opening one file and a couple of clicks — easily fifteen minutes saved per document.
• A professional impression: a fast reply with a signed contract comes across as more reliable than a day's delay while you hunt for a printer.
• Less reliance on equipment: you don't need a printer or scanner at home or in the office, just a Mac.
• Less paper: the document stays digital from start to finish, which also helps when you need to look up an older contract in your email later.

Pro tip

For important contracts where the legal weight of the signature matters (not just its appearance), consider a service with an electronic signature, like DocuSign or Adobe Acrobat Sign — those add a verifiable timestamp and audit trail to the signature, which a visual signature in Preview doesn't offer.