Guide

How to sign a PDF on iPhone or iPad

By Prakrin Kumar, who builds PDFPivot and VidPivot at The Nexus Pivot. Last updated 27 July 2026.

iOS already includes a free way to sign a PDF — Markup. You don't need a dedicated app just to drop one signature on one document. Here's how to do it with what's already on your phone, and where a fuller PDF app actually earns its place.

Key takeaways

• Built-in option: Markup, free, reachable from the Share sheet or Quick Look in Files — genuinely fine for a quick signature.
• App option: PDFPivot (our app) when you want signing alongside editing, scanning, and form-filling in one place.
• Internet: Not needed for either. Signing on-device works fully offline.
• Cost: Free either way for basic signing.

What's the fastest way to sign a PDF on iPhone or iPad?

Open the PDF, tap the Markup icon from the Share sheet, Quick Look, or inside Mail or Files, choose the signature tool, draw or place your signature, drag it onto the line, and save. No printing, no scanning, no upload.

What can Markup do for free — and when do you need more?

Markup lets you draw a signature with your finger or Apple Pencil, save it for reuse, and drop it — plus text, checkmarks, and other marks — onto a PDF from Files, Mail, Notes, or Photos. For a single document that just needs one signature, that's the whole job, done for free, on-device.

It gets less convenient when you're signing several documents in a row, want the same saved signature available as part of a bigger workflow — editing, scanning, and compressing a file before it gets signed and sent — or need to fill in a PDF's actual form fields rather than draw over them. One thing worth checking: if you mark up a copy of a PDF from inside a Mail draft or a Quick Look preview, that signed version is tied to that particular copy. Save it back to Files afterward, and confirm the saved file has the signature, rather than assuming it carried over automatically.

How do you sign a PDF on iPhone or iPad, step by step?

1. Open the PDF — in Files, or as an attachment in Mail or another app.
2. Tap the Markup icon from the Share sheet or Quick Look — or open PDFPivot (disclosure: it's our app) if you'd rather sign inside the same app you use to edit, scan, or compress the file.
3. Choose the signature tool, then draw your signature with your finger or Apple Pencil, or reuse a signature you saved earlier.
4. Drag it into place, resize if needed, fill in any remaining fields, and save the file back to Files — On My iPhone or iCloud Drive.

What can go wrong when signing a PDF on iPhone?

• There's no visible line to place your signature on. Not every PDF has a defined signature field — drag your signature image to wherever it needs to sit on the page manually.
• The signed version isn't in Files afterward. If you marked up a copy from a Mail draft or a temporary preview, save it back to Files explicitly and check the saved file, rather than assuming the signature carried over.
• You can't type into the form fields. Some PDFs are "flat" — scanned or exported without real form fields — so there's nothing to detect. Place a free text box wherever it needs to go instead.

Need to fix the document itself first? See our guide to editing PDF text on iPhone, or if you're starting from paper, scan it to PDF before signing. Signed a large file? Compress it before you email it on. For tools that never upload your document, see our offline PDF editors comparison.

Frequently asked questions

Can I sign a PDF for free on iPhone?

Yes. Markup, built into iOS, adds a drawn or saved signature to a PDF at no cost, reachable from the Share sheet or Quick Look in Files. PDFPivot (our app) includes the same kind of signing alongside editing, scanning, and compressing in one place.

Is a signature added on an iPhone legally valid?

A drawn or placed signature counts as an electronic signature in most everyday contexts — leases, forms, informal contracts. In the US, the ESIGN Act (2000) gives electronic signatures the same legal weight as a handwritten one for interstate and foreign commerce. For documents needing a certified digital signature or notarization, check the recipient's specific requirements first.

Why use an app instead of Markup to sign a PDF?

Markup is genuinely enough for a single quick signature. An app like PDFPivot helps more when you're also editing text, filling several form fields, scanning the document in the first place, or want your saved signature and the rest of your PDF work in one app instead of switching to Markup each time.