How to sign a PDF on iPhone without Adobe

You opened a PDF to sign, tapped through to Adobe Acrobat, and hit a wall: create an account, verify an email, maybe a “start your free trial” prompt before you can drop a signature. For a one-line signature on someone else’s form, that’s a lot of friction for something your iPhone can already do.

Here’s the honest truth: you don’t need Adobe to sign a PDF on an iPhone. Two routes below — the free one built into iOS first, then a faster app if you sign documents regularly.

The free way: iOS Markup (no app, no account)

Every iPhone can sign a PDF without installing anything. The tool is Apple’s built-in Markup, and it’s already on your phone:

Open the PDF — in Files, in Mail (tap the attachment), or in Photos if it’s a scan.
Tap the Markup icon (the pencil tip in a circle) in the top corner.
Tap + in the bottom-right, then Signature.
Draw your signature with your finger, or pick one you saved earlier. Tap Done.
Drag the signature onto the signature line, resize it with the blue handles.
Tap Done again, then Share to send the signed copy back.

That’s it — no Adobe, no login, nothing uploaded to a company’s servers. If you sign something once or twice a year, stop here. Markup genuinely covers you.

Where Markup starts to hurt, honestly: the signature is a raw finger-drawing on glass, so it takes a few tries to get one you’d actually put your name to. Dates and initials are manual text boxes you nudge into place one at a time. And a multi-page contract that needs your initials on every page turns into real, repetitive work.

The faster way: a signature app built for signing

If a signature line shows up in your life more than occasionally — leases, school forms, work paperwork, contractor quotes — a dedicated app changes the math. You set your signature up once, and every document after that is a few taps.

Signed is built for exactly this, and like Markup it needs no account to start signing:

Open the PDF and tap Share → Signed (or import it from Files).
Your saved signature, initials and an auto-filled date are one tap each — drop them where they belong. You create your signature once: draw it properly, type your name in a real handwriting style, or let AI generate one from your name.
Tap Finish for a clean, flattened PDF, and share it straight back.

The part that matters if you left Adobe over privacy: the big e-sign services are built to upload your document to their cloud — that’s how they route it to other signers. For receiving and returning a document yourself, you don’t need any of that. Signed is local-first: the PDF never leaves your phone, and there’s no cloud copy of what you signed.

So which one?

You sign twice a year → iOS Markup. Free, built in, done. No Adobe, no app.
You sign monthly or more, or want it to look like your real signature → an app that keeps your signature ready pays for itself the first week, mostly in avoided fiddling.
The document is high-stakes legal work → whatever tool you use, dropping a signature image on a PDF may not be the whole requirement. It’s worth checking what’s actually needed for that specific document before you rely on it. Signed is a signing tool, not legal advice.

Either way, the account-and-trial gate you just hit was never the price of signing a PDF on your phone.