How to rotate a sideways PDF before signing it on iPhone

A PDF arrives, you open it, and the whole page is lying on its side. You tilt your head, read it anyway, sign it, send it back — and the person on the other end opens a document that is still sideways.

Before anything else, the one thing worth knowing: rotating what’s on your screen is not the same as rotating the file. Most viewers will happily turn the page for you and change nothing inside the PDF. That’s the trap this whole page exists to get you out of, and it’s why “I already rotated it” and “it arrived sideways” are both true at once.

So the job is to rotate the page permanently, save it, and only then sign.

The free fix: the Files app (no app needed)

Apple’s Files app can rotate PDF pages and save the change into the file. It’s free, it’s already on your iPhone, and for most people this is the entire answer:

Save the PDF into Files if it isn’t there yet — from Mail, tap the attachment, then Share → Save to Files.
Open it in Files and tap the pencil (Markup) icon.
Tap the page-thumbnails icon in the top corner to show the pages down the side.
Long-press the sideways page → Rotate Left or Rotate Right. Repeat until it’s upright.
Do the same for any other page that needs it — a scan is often all sideways, or maddeningly, only page 3.
Tap Done. The rotation is written into the file.

Close it, reopen it, and check. If it opens upright now, the fix stuck — that reopen is worth the three seconds, because it’s the difference between fixed and only-looked-fixed.

Two honest caveats. If the PDF is password-protected you’ll have to unlock it first — signing a password-protected PDF on iPhone covers that order of operations. And if the document was locked down as read-only by whoever sent it, no phone app is going to rewrite its pages; ask them for an unlocked copy.

If it’s a photo, not a PDF

A picture of a page taken sideways is a different problem with an easier fix: open it in Photos → Edit → the crop tool → the rotate button, then Done. The photo is now the right way up wherever it goes next.

But if you’re about to sign it, rotating isn’t really the fix you want. A phone photo of paper comes out shadowed, crooked and grey, and a rotated crooked photo is still a crooked photo. Re-capture it with the free scanner in Notes or Files (⋯ → Scan Documents) instead — it detects the page edges, straightens it and hands you a clean, upright PDF. Signing a photo of a document on iPhone goes through that in full, including how to get a PDF back rather than a JPEG.

If you have a Mac nearby

Preview is the most reliable rotation tool Apple makes, and it takes five seconds: open the PDF, show the thumbnail sidebar (View → Thumbnails), select the pages, press ⌘R until they’re upright, then ⌘S. Worth knowing about for the stubborn files — occasionally a PDF has been assembled in a way that the phone viewer won’t rewrite, and Preview just does it.

Now sign it

With the page upright, this is ordinary signing, and you have the usual two routes.

Free, built in: you’re already in Markup, so tap + → Signature, draw one with your finger, drag it onto the line, resize with the handles, Done. For a one-off document, that’s the end of it — you don’t need an app for this.

If documents keep arriving: Signed imports the rotated PDF from Files and drops your saved signature, initials and today’s date with a tap each, then exports a flattened PDF — the signature merged into the page rather than floating on top as an annotation. You build the signature once, properly: draw it, type your name in a real handwriting style, or let AI generate one from your name. If you just want to see what a decent one looks like first, the free signature generator runs in your browser with no signup.

To be straight about it: Signed doesn’t rotate PDF pages. Rotation is Apple’s job here, it’s free, and it takes about ten seconds in Files. Signed picks up after the page is upright — which is the part you’ll do again next week, and the week after.

On privacy: the documents that arrive sideways are usually scans, and scans are usually the ones you’d rather not upload anywhere — bank letters, IDs, signed agreements. Files rotation happens on your phone, and Signed is local-first, so nothing about this round trip needs a server.

Why it happened, so it doesn’t happen again

A scanner fed the page in landscape. Office multifunction scanners do this constantly, then email you the result without looking.
A photo carried sideways orientation data into a PDF conversion, which then baked it in.
The page really is landscape — a floor plan, a spreadsheet export, a wide table. That one isn’t broken, and rotating it will make it worse. Sign it as it is.
Someone rotated the view, not the file, and sent it on believing it was fixed. Now you know that one from both sides.

If the sideways scan came from your own paperwork, capture it with a document scanner rather than the camera next time — signing a scanned document on iPhone covers getting a straight, upright scan in the first place, which removes this step entirely.

The short version

Rotate the file in Files (Markup → thumbnails → long-press → Rotate), not just the view.
Reopen it to confirm the rotation saved.
Sign the upright page — Markup for one-offs, Signed if this keeps happening.
Send it back the right way up.