Electronic signatures and digital signatures: what is the difference?

“Sign and return” no longer means print, sign, scan. But the words used for signing online, such as electronic signature, digital signature and e-signature, are often used as if they mean the same thing. They don’t, and the difference matters when you decide how to sign a document.

This article is general information about how the technology works, with a brief overview of the UK position. It isn’t legal advice. If a document is important or unusual, check what the person asking for your signature will accept, or ask a solicitor.

Electronic signatures

An electronic signature is any electronic way of showing that you agree to a document. That includes typing your name at the end of an email, ticking an “I agree” box, drawing your signature on a touchscreen, or placing an image of your signature on a PDF. What they have in common is intent: they show you meant to sign.

Visual signatures, the kind created by Sign PDF, are electronic signatures. They are quick, need no special software and are widely accepted for everyday documents.

Digital signatures

A digital signature is a specific technology that uses cryptography and a digital certificate. When a document is digitally signed:

• a unique fingerprint (hash) of the document is calculated;
• that fingerprint is encrypted with the signer’s private key, which only they hold;
• anyone can check it using the signer’s public certificate, usually issued by a trusted certificate authority.

This proves two things a visual signature can’t: who signed (as far as the certificate can be trusted) and that the document hasn’t changed since. Edit a digitally signed PDF and readers will warn that the signature is no longer valid.

Side by side

The position in the UK, briefly

English law has long taken a flexible view of signatures: what usually matters is that the signer intended to authenticate the document. The Electronic Communications Act 2000 recognises electronic signatures as evidence, and the Law Commission’s 2019 report on electronic execution concluded that an electronic signature is generally capable of validly executing a document, including one that must be “signed”, provided the signer intends to authenticate it and any formalities are met.

Some documents come with extra formalities. Deeds, such as certain property documents and powers of attorney, normally need a witness, and the Law Commission’s view is that the witness should be physically present. Some organisations, such as HM Land Registry, run their own processes for electronic signing. Wills have specific requirements of their own. For these, a picture of a signature is unlikely to be enough on its own.

The UK also has rules, inherited from the EU’s eIDAS regulation, that define advanced and qualified electronic signatures, which use certificates and identity checks. They are used where a higher level of assurance is needed.

Choosing the right approach

• Everyday paperwork such as a school trip form, a quote acceptance or a tenancy renewal sent by your agent: a visual signature is normally fine. If the sender uses an e-signing platform, use that.
• Documents where tampering is a concern: ask for a certificate-based digital signature, or use an e-signing service that keeps an audit trail.
• Deeds, wills and property transfers: follow the specific instructions you’re given; don’t assume an image of your signature will do.

Good habits when signing PDFs

1. Read the whole document first, including small print and any pages after the signature line.
2. Add the date next to your signature if the document asks for it.
3. Flatten the signed PDF so form entries and your signature can’t be moved accidentally.
4. Keep a copy of exactly what you signed.
5. Be careful where you store image files of your signature.