How to sign a PDF on your phone

Updated 8 November 2026

Short answer: open the PDF in a PDF app, tap Sign, draw your signature with your finger, drag it onto the signature line and save. On an iPhone you can also use Markup in the Files app. For forms, reusable signatures and initials, an app like PDF Editor is faster.

How to sign a PDF on your phone

1. Open the PDF. Open the PDF in PDF Editor, or in the Files app on iPhone, from your email, cloud storage or a scan.
2. Add a signature. In PDF Editor, choose Sign and draw your signature or use a photo of it. On iPhone without an app, tap Markup, then +, then Add Signature.
3. Position it. Drag the signature onto the signature line and resize it.
4. Complete the form. Fill in your name, the date and any other fields.
5. Save and send. Save the PDF and send it by email, print it, or fax it.

Is an electronic signature valid in the UK?

In England and Wales, an electronic signature, including a signature drawn on a phone, is generally capable of being legally valid for contracts, as long as the person intends to sign. The Law Commission confirmed this in its 2019 report on electronic execution of documents, and the Electronic Communications Act 2000 allows electronic signatures as evidence. Scotland and Northern Ireland have similar rules.

There are exceptions. Some documents need a witness, a deed may have extra formalities, and some organisations (for example, HM Land Registry for certain documents) set their own requirements. This guide is general information, not legal advice; if a signature really matters, check with the organisation asking for it or a solicitor.

Tips

• Save your signature and initials once, then reuse them.
• Zoom in before placing the signature so it sits neatly on the line.
• Send the signed file as a PDF, not a screenshot, so it stays sharp and can't be easily changed.
• Need to send it by fax? Use the FAX app straight from your phone.