How to sign a PDF on your phone (iPhone and Android)

Someone emails you a form "to sign and return". You're not at a desk, you don't have a printer, and the last thing you want is to install a new app and create yet another account.

You can sign a PDF directly in your phone's browser. This guide walks through it on iPhone and Android, and covers the questions people usually have about whether an electronic signature "counts".

What you need

• The PDF, saved on your phone (from email, a messaging app or your files).
• A browser: Safari, Chrome, Firefox or Samsung Internet all work.
• About two minutes.

Step by step

1. Save the PDF to your phone

• iPhone: open the attachment, tap the share icon, then Save to Files.
• Android: open the attachment and tap the download icon; it goes to Downloads.

2. Open Sign PDF

Go to Sign PDF and tap the area to add a file. Choose the PDF you just saved.

[Screenshot] Sign PDF on a phone, with the file picker open.

3. Create your signature

You have two choices:

• Draw: sign with your finger in the box. Turn the phone sideways for more room. If it doesn't look right, clear it and try again.
• Type: type your name and it's shown in a handwriting-style font.

[Screenshot] The signature pad with a finger-drawn signature.

4. Place it

Choose the page (usually the last), the position on the page and the width. Adjust the width so the signature fits the signature line on the form. You can also add today's date below the signature; it's written in the format of the language you use the site in.

5. Sign and download

Tap Sign PDF and download the signed copy. Then send it back from your email app as an attachment.

The document and your signature stay on your phone. Nothing is uploaded, and your signature isn't saved anywhere.

Drawn or typed: which should I use?

Both are simple electronic signatures, so the choice is mostly about what the recipient expects:

• Draw when the document will be compared with your usual signature, such as a lease, a bank form or anything you'd normally sign by hand. It looks the most like your paper signature.
• Type when speed matters more than looks, or when drawing with a finger is awkward (in a moving vehicle, for example). A typed name is clear and always legible.

Whichever you pick, use the same style for every place in the same document, and keep it consistent with what you've used with that organisation before.

Signing in more than one place

Some documents need a signature on several pages, or initials at the bottom of each page. Run the tool once for each place: sign, download, then open the downloaded file and sign the next spot.

If the form also has blanks to fill in (name, address, date), do that first with Fill PDF form, then sign the filled-in copy.

Is an electronic signature legally valid?

In many countries a simple electronic signature (an image of your signature placed on the document, which is what this tool does) is accepted for everyday agreements: rental contracts, consent forms, school permissions, delivery confirmations and the like.

Some documents need more: notarised deeds, certain government filings, or contracts where the law requires a qualified or certificate-based digital signature. Those involve a verified identity and a cryptographic certificate, which a drawn signature doesn't provide.

If you're unsure, ask whoever sent you the document what they accept. Most people sending a PDF "to sign and return" expect exactly this.

This article isn't legal advice.

Making it harder to tamper with

A signature placed on a PDF is part of the page, but anyone with a PDF editor could still change the document afterwards. To make that harder:

• Flatten the PDF with Flatten PDF if it has form fields, so filled-in answers can't be edited.
• Protect it with a password using Protect PDF before emailing, and send the password separately.
• Keep your own copy of what you signed.

Troubleshooting

The signature looks shaky. Draw slower and bigger; the signature is scaled down to the width you choose, so a large, slow signature looks smooth when placed.

I can't find the downloaded file. On iPhone, check Files → Downloads (or On My iPhone). On Android, open the Files or Downloads app.

The form fields are empty after signing. Fill the form first and download it, then sign that copy.

The page is sideways. Fix it first with Rotate PDF, then sign.

Frequently asked questions

Do I need to install an app? No. It works in your phone's browser.

Is my signature stored? No. It's created on your phone, placed on the page and never sent to us.

Can I sign a PDF that has a password? If the PDF needs a password to open, remove it first with Unlock PDF (you need to know the password).

Does it work on a tablet or computer too? Yes, the same tool works on any device; on a computer you can sign with a mouse or trackpad.