How to Sign Documents on iPhone
The iPhone can already put a signature on a PDF: open it in Files or Mail, tap Markup, and draw. That is fine for a permission slip. For a lease, a contractor agreement or anything you might need to prove later, a drawn image is not enough on its own. What matters is a record of who signed, when, and that the document did not change afterward.
Markup puts ink on a page, not a signature on a record
A Markup signature is a drawing saved into the PDF. It records nothing about who drew it, and the file can be edited and re-saved after the fact. If the other side later says the price was different, or that they never signed, a marked-up PDF does not answer either claim. For low-stakes documents that is acceptable; for agreements with money or obligations attached, it is the wrong tool.
What the template covers
Sign in Safari, nothing to install
Open the signing link, read the whole document, and sign with your finger. No App Store download, no account for the signer.
Face ID confirmation when it matters
For important documents, the sender can require the signer to confirm with Face ID or Touch ID on their own iPhone, the same way they unlock it.
An audit trail on every signature
Each signature records the date, time, IP address and device, plus a SHA-256 fingerprint of the document that breaks if anything changes after signing.
Send it on by text or email
Send your own document for signature from the iPhone by text, email or a QR code, and everyone receives the signed PDF with its certificate.
Is a signature on an iPhone legally binding?
The Electronic Signatures in Global and National Commerce Act, 15 U.S.C. § 7001, provides that a signature, contract or record may not be denied legal effect solely because it is in electronic form, and every state except New York has adopted the Uniform Electronic Transactions Act; New York reaches the same result through its Electronic Signatures and Records Act. Neither law cares what device was used. What they require is intent to sign and a record that can be retained and reproduced. A signature with an audit trail and a tamper-evident seal satisfies both, and gives you evidence of attribution if anyone disputes it.
A lease signed in a parking lot
A tenant in Phoenix found the apartment she wanted on a Saturday, but the landlord was out of town until Wednesday and had another applicant lined up. He texted her the lease link; she read it on her iPhone in the parking lot, confirmed with Face ID, and signed. He countersigned from his phone an hour later and she had the keys arranged by Monday.
Before you sign on your iPhone
- Scroll through every page, including schedules and attachments, before signing.
- Check that names, dates and amounts match what you agreed.
- Use Face ID confirmation when it is offered: it ties the signature to you.
- Download or keep the emailed copy with its signature certificate.
Questions people ask about this
Can I sign a PDF on iPhone for free?
Yes. Signing a document someone sent you is free and needs no app or account.
Is the iPhone Markup signature legal?
It can be, but it carries no record of who signed or proof the document did not change. For important agreements, an e-signature with an audit trail is far stronger evidence.
Do I need an app to sign on iPhone?
No. Signing happens in Safari. You can add the site to your home screen if you sign often.
Can I sign a document from the Files app?
Yes. Upload it from Files, iCloud Drive or Google Drive, place your signature, and download it signed or send it to others to sign.