How to Sign a PDF on iPad

01

The Markup route, in about twenty seconds

Open the PDF in Files or tap it in Mail, then tap the Markup icon. Tap the + at the bottom right, choose Signature, and either pick a signature you have saved or draw a new one. Drag it to where it belongs, pull a corner handle to size it, and tap Done. The signature is stored in iCloud, so it appears on your Mac and iPhone too.

If the signature is going somewhere obvious — a signature line at the foot of a contract — that is the entire job. Mail it back and you are finished.

02

Why a Pencil signature is worth the extra ten seconds

A signature drawn with a fingertip is a thick, wobbling stroke of roughly constant width, because a fingertip is a blunt contact patch about a centimetre across. It reads as a signature the way a child's drawing of a car reads as a car.

A Pencil signature is sampled at the tip, at high rate, with tilt and pressure — so it has the thin entries, the thick down-strokes and the loose tail that make your handwriting yours. If the document is going to anyone who has seen your signature before, this is a real difference, and it is the single best argument for signing on an iPad rather than a laptop.

Draw it once. Markup saves it and every future signature is two taps.

03

The part nobody mentions: Markup does not flatten

A Markup signature is stored as a PDF annotation — an object floating above the page, not part of it. That is why you can move it after placing it. It is also why, in some readers, it can be selected, dragged off, or deleted by the person you sent it to. Print it and it prints; open it in a viewer that ignores annotations and it may not appear at all.

For most correspondence this does not matter. For anything that will be filed, forwarded, or archived — a lease, a contract, an employment form — flattening is worth the extra step. Flattening merges the annotation layer into the page itself, so the signature becomes part of the picture and stops being an object anyone can pick up.

There is no flatten command in iPadOS. Running the file through the flatten tool afterwards is the whole fix, and it takes a few seconds on the iPad itself.

Sign, then flatten

Markup places the signature; flattening makes it permanent and identical everywhere.

Or sign in the browser

The signing tool draws onto the page and flattens in one pass, so there is no second step.

Then lock it if it matters

An owner password blocks casual editing of the signed file. It is a deterrent, not a guarantee.

04

When the form has more than a signature on it

Most things needing a signature also need a date, a printed name, and three boxes ticked. Markup's text tool will do it, but the type sits where you drop it rather than snapping to the form's own fields, and it is fiddly on a form built for a real PDF form-filler.

If the PDF has proper interactive fields, fill them in a viewer that supports them and flatten at the end — flattening turns the filled fields into printed text so the recipient sees values rather than empty boxes. If it is a flat scan with no fields, Markup's text tool with the Pencil and Scribble is genuinely quicker than typing.

05

Is a signature drawn on an iPad legally binding?

In most of the world, yes, for most everyday agreements. The eIDAS regulation in the EU and the ESIGN Act in the US both recognise electronic signatures broadly, and a drawn mark applied with clear intent is a valid electronic signature under each.

What a drawn signature does not carry is cryptographic proof of who applied it. That is a different thing — a digital signature backed by a certificate — and it is what a handful of documents genuinely require: some property transfers, some court filings, some notarised instruments. If a document tells you it needs a qualified or certified signature, a Pencil drawing is not it, and no amount of flattening changes that.