Are electronic signatures legally binding? UK, EU and US, explained

If you send agreements for a living, as a founder, a studio or an independent consultant, you've probably wondered whether a signature captured on a screen actually counts. The short answer is yes: in the UK, the EU and the US, electronic signatures are legally binding and enforceable for the vast majority of business agreements.

But "legally binding" and "provable in a dispute" are two different things. Here's what the law says, and what actually matters.

The UK and EU: eIDAS

In the EU, and in the UK where it was retained after Brexit, electronic signatures are governed by the eIDAS regulation. It recognises three tiers:

• Simple electronic signatures (SES), a name typed or drawn to indicate intent. Valid and admissible for most commercial contracts.
• Advanced electronic signatures (AES), uniquely linked to the signer and capable of detecting later changes to the document.
• Qualified electronic signatures (QES), AES backed by a qualified certificate, given the same legal status as a handwritten signature.

Crucially, eIDAS says an electronic signature can't be denied legal effect simply because it's electronic. For a services agreement, an SOW or an NDA, a simple electronic signature is almost always enough.

The US: ESIGN and UETA

In the United States, two laws do the work: the federal ESIGN Act (2000) and the state-level UETA, adopted in nearly every state. Together they establish that a contract or signature "may not be denied legal effect… solely because it is in electronic form." The requirements are practical: intent to sign, consent to do business electronically, association of the signature with the record, and retention of that record.

What actually makes it hold up

Enforceability rarely fails on the format of the signature. It fails on evidence. If a signature is ever challenged, you need to show who signed, that they intended to, and that the document hasn't changed since. That's why the record matters more than the pen:

• A capture of intent and consent at the moment of signing.
• An audit trail of who opened, reviewed and signed, when, and from where.
• Tamper-evidence, proof the executed document is byte-for-byte the one that was signed.

The signature proves who. The record proves what, when and that nothing changed.

This is exactly where a lot of "just email a PDF back" workflows fall down. There's no record, no consent capture and nothing stopping a page being swapped later. A purpose-built tool captures all of it automatically.

How Signet handles it

Every agreement sent with Signet records an append-only, tamper-evident audit trail, opened, reviewed, signed, sealed, and seals the completed document with a verifiable certificate of completion. Any change is detectable, so tampering shows. It's aligned with eIDAS, ESIGN and UETA, so what you send is enforceable and, just as importantly, provable. You can read more on our security page.

This article is general information, not legal advice. For high-value or regulated agreements, check the specific requirements in your jurisdiction.

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