Simple electronic signature (SES)

What does Simple electronic signature mean?

A simple electronic signature (SES) is the most basic type of electronic signature recognized under the EU's eIDAS regulation: data in electronic form that is attached to or logically associated with other data and used by the signatory to sign. A typed name at the bottom of an email, a signature drawn with a finger on a phone, a scanned signature image, or a click on an "Accept and sign" button can all be simple e-signatures.

eIDAS sets no technical requirements for this level. That is the point: it covers the huge range of ordinary ways people signal agreement electronically. What it does guarantee, under Article 25, is that a court cannot refuse a signature as evidence just because it is electronic or falls short of the qualified level. How much weight the signature carries then depends on the evidence behind it.

In a typical workflow, a landlord in Ireland sends a tenancy renewal PDF to a tenant. The tenant opens the link, reads the document, types their name, and confirms. The platform logs when the email was sent, when the document was opened, the IP address and device used, and the moment of signing, then locks the final PDF and computes its hash. That bundle of evidence is what gives the simple signature its strength.

The most common misconception is that simple means weak or informal. In both the EU and the US, simple electronic signatures are used for a vast share of everyday contracts, including sales agreements, NDAs, employment paperwork and service terms. The US ESIGN Act does not even use the simple, advanced and qualified tiers; it treats all electronic signatures as valid if the usual requirements such as intent and record retention are met.

The trade-off is proof of identity. A simple signature does not by itself verify who the signer is, which is where an advanced electronic signature adds requirements such as unique linkage to the signer. For higher-risk documents, stronger signer authentication can close part of that gap.

eSignSimple provides simple electronic signatures, and we are upfront about that. Signers need no account; they receive a link, sign, and every document ends with an audit trail, certificate of completion and a SHA-256 hash that can be checked on our public /verify page. Extra identity checks such as one-time codes and ID verification are on our roadmap.

Our take: simple electronic signatures are the right default for most small businesses. The label undersells them. Pair them with good records and clear consent, and save heavier signature levels for the documents where the law or the stakes genuinely call for them.

What is an example of simple electronic signature?

A yoga studio owner in Ireland needs new members to sign a liability waiver before their first class. She turns her waiver into an eSignSimple web form, members fill in their name and sign on their phone at the front desk, and each submission produces a signed PDF with a timestamped audit trail. That is a simple electronic signature, and it is the right tool for a routine waiver like this.

How can you make a simple electronic signature stronger as evidence?

A simple signature is only as good as the record around it, and most of that record is decided before you press send. Use the signer's own email address, not a shared team inbox. Name each signer exactly as they appear in the contract, so the certificate and the parties clause match. Add initials fields on key pages, such as the payment terms or a non-compete clause, so nobody can claim they only saw the signature page. If one party should sign before the other, set a signing order so the sequence is recorded rather than assumed.

After completion, keep the signed PDF as delivered and do not re-save it, because the fingerprint recorded at completion only matches the untouched file. If a document carries more risk than usual, add a step outside the platform: a short phone or video call confirming the signer received it, noted in your files. That kind of signer authentication evidence is cheap and often more convincing than any technical feature.

SES, AES or QES: which level fits which document?

Here is the decision guide we use. Simple signatures fit the large majority of business paperwork: NDAs, freelance and consulting agreements, sales contracts, offer letters, policy acknowledgments, waivers, quotes and most leases. Advanced signatures make sense where stronger identity evidence is commercially useful or expected, such as some financial onboarding, higher-value cross-border agreements, or when a large customer's procurement rules ask for it. Qualified signatures belong where national law requires a handwritten-equivalent signature, such as certain statutory written-form requirements, some public tenders and some corporate filings.

And some documents need none of these, because they need a notary, a witness or paper. If you are unsure, the question to ask is not which signature is strongest but whether a rule specifically requires more than a simple signature for this document in this country. If the answer is no, a simple signature with a good audit trail is the efficient choice. Our EU legality overview notes where member states add requirements.

What does a challenge to a simple signature look like?

Take a small marketing agency whose client stops paying and then claims never to have signed the retainer. The agency produces the signed PDF and the certificate of completion. It shows the request went to the client's work email, the document was opened two days later, the signer accepted the consent to use electronic records, and the signature was applied from a particular IP address and browser. The agency also has the client's emails before and after that date referring to the work.

In most cases that combination is persuasive, because the client would have to explain how someone else accessed their work inbox and why they then behaved as if the contract existed. A simple signature loses when the record has gaps: the link went to a shared address, the signer's name does not match the email, or the file offered in evidence has been re-saved and no longer matches its recorded fingerprint. Close those gaps and the simple level holds up well.

Which terms are related?

• Electronic signature: An electronic signature is any electronic sound, symbol or process attached to a record and adopted by a person with the intent to sign it.
• eIDAS: eIDAS is the EU regulation (No 910/2014) on electronic identification and trust services, including electronic signatures.
• Advanced electronic signature (AES): An advanced electronic signature is uniquely linked to and identifies the signer, is under their sole control and detects later changes to the data.
• Qualified electronic signature (QES): A qualified electronic signature is an advanced signature created with a qualified device and backed by a qualified certificate from a QTSP.
• Audit trail: An audit trail is a chronological record of events in a document's signing process, such as sending, viewing and signing, with timestamps.