Searching for the different types of digital signatures?
You might be wondering which is best for your needs, or you may well be trying to differentiate the three recognised levels of electronic signature:
- Simple electronic signatures
- Advanced electronic signatures
- Qualified electronic signatures
Each provides a different level of assurance about the person signing a document, the document’s integrity, and the evidence available if the transaction is questioned later.
Read on to learn more about the different types of digital signatures and help decide which is best for your needs.
What is a digital signature?
A digital signature is a cryptographic method used to verify the authenticity and integrity of a digital document, message, or other electronic data; put more simply, it’s a way to sign a document online that also helps prove who signed it and whether the document was changed afterwards.
Think of it as an electronic signature with a built-in security check.
Unlike an image of a handwritten signature, a digital signature is mathematically connected to the information being signed. If someone changes that information after the signature has been applied, the digital signature verification should fail.
Digital signatures normally use public key infrastructure, commonly known as PKI. This involves a private key used during the signing process and a corresponding public key that allows a recipient or relying party to verify the signature. A digital certificate links the public key to the person identified in the certificate.
The technology is designed to support three important outcomes. Authentication increases confidence in the signature’s source. Document integrity helps show whether the signed information has been changed. Non-repudiation provides stronger evidence linking the signing action to the responsible person or organisation.
A digital signature does not necessarily encrypt the contents of a document or prevent people from viewing it. Its main purpose is to protect authenticity and integrity. You can use separate encryption when the contents also need to remain confidential.
Electronic signature vs digital signature
Although electronic signatures and digital signatures have many similarities, they are not the same thing.
An electronic signature describes an electronic action someone uses to demonstrate their intention to approve, accept, or authenticate a document. Typing a name, inserting a scanned signature, drawing a signature on a screen or clicking an “I accept” button can all count as electronic signatures.
A digital signature is more complex. It is the technology behind a more secure electronic signing process. It uses cryptography and digital certificates to link the signature to the signed information and show whether that information has been altered.
Digital signatures are often used to support electronic signatures, but not every electronic signature uses digital signature technology. A typed name can show intent without being cryptographically linked to the document.
This means you need to consider both parts of the transaction. You need evidence that the person intended to sign, but you may also need to identify that person and protect the integrity of the completed document. Especially now, when AI and deepfakes are so prevalent in fraud.
What are the three main types of electronic signature?
The three main types of electronic signature recognised within the eIDAS framework are Simple Electronic Signatures, Advanced Electronic Signatures and Qualified Electronic Signatures. They are normally shortened to SES, AES and QES.
Each level builds on the previous one by adding requirements for signer identification, control, authentication, and document integrity.
A simple, advanced and qualified signature could all display the signer’s typed or handwritten name. What separates them is the process behind the signature and the evidence that process creates.
Simple electronic signature, suitable for everyday transactions
A SES is the simplest form of electronic signature. It may involve a person typing a name into an electronic document, adding a scanned image of a handwritten signature, drawing a signature with a mouse or finger, selecting a tick box or clicking a button to confirm acceptance.
An SES can provide useful evidence that someone intended to approve a document, but does not require strong authentication or identity verification, basically the person signing is who they say they are. In some signing processes, access to an email account or possession of a signing link may be the only connection between the signature and the intended signer.
For low-risk or routine transactions, this may be all you need. Examples include internal approvals, straightforward supplier paperwork, everyday sales documents or agreements between parties with an established relationship.
However, you should understand its limitations. If the signature is disputed, it may need to rely on contextual information, email records, access logs and other evidence to show who completed the process.
A Simple Electronic Signature should not automatically be described as invalid or non-binding. Its legal effectiveness depends on the signer’s intention, the available evidence and whether any formal requirements applying to the document have been met. The more important question is whether it provides an appropriate level of assurance for the transaction.
Advanced electronic signature, stronger signer authentication
An Advanced Electronic Signature provides stronger, more direct evidence linking the signature, the signer, and the document.
An AES must be uniquely linked to the signer and capable of identifying them. It must be created using signature-creation data the signer controls. It must also be connected to the signed information in a way that makes subsequent changes detectable.
These requirements make an AES more suitable for transactions that require stronger proof of identity and protection of the document’s integrity.
The process may include mobile verification, a one-time access code, a government-issued identity document, biometric verification or a digital certificate. The actual authentication method will depend on the requirements of the transaction.
Advanced signatures may be used for employment agreements, financial documents, client engagement letters, sensitive commercial contracts and other transactions where basic email access does not provide enough assurance on the person behind the signature.
However, the AES label alone does not give everything it needs to know. The strength of the signature still depends on the checks used to identify the signer, how securely the signature creation process is controlled and what evidence is retained.
Qualified electronic signature, the highest level of assurance
A Qualified Electronic Signature is an Advanced Electronic Signature which provides the highest level of assurance within the eIDAS framework.
A QES is supported by a qualified certificate and created using an approved qualified signature creation process. The signer’s identity must be verified through a qualified process before the relevant certificate is issued.
Qualified Electronic Signatures are used when you need strong evidence of identity, intention and document integrity. This can include regulated financial agreements, property transactions, formal legal documents, corporate transactions and other high-value or legally sensitive activities.
The qualified certificate links the digital signature to a verified identity. The signing process also produces evidence that can be used to validate the signature and determine whether the document has changed.
| Factor | Simple Electronic Signature | Advanced Electronic Signature | Qualified Electronic Signature |
| Abbreviation | SES | AES | QES |
| Typical assurance | Basic | Enhanced | Highest |
| Identity verification | Not necessarily required | Must be capable of identifying the signer | Verified identity connected with a qualified certificate |
| Link to the signer | May rely on contextual evidence | Uniquely linked to the signer | Strongly linked through qualified identity and certificate controls |
| Signer control | Limited formal requirements | Created using data under the signer’s control | Created through an approved qualified signature process |
| Document integrity | Depends on the platform | Subsequent changes must be detectable | Strong integrity and qualified certificate controls |
| Typical uses | Routine and lower-risk documents | Higher-value or identity-sensitive documents | Regulated and legally sensitive transactions |
| Supporting evidence | Basic transaction records | Stronger authentication and audit evidence | Qualified certificate and high-assurance evidence |
How Is the signer’s identity verified?
A simple signing process may confirm that the signer can access a particular email address or mobile phone. This does not prove that the person behind the screen is genuinely who they claim to be.
A higher-assurance process may ask the signer to provide a government-issued identity document, complete a biometric face match or perform a liveness check. The system can then assess whether the document is authentic and whether the person presenting it matches the identity shown.
For regulated businesses, this matters as capturing a signature does not necessarily prove the identity of the person who supplied it.
Legal practices, financial services providers and other regulated businesses may need to demonstrate that they took reasonable steps to identify the customer, authenticate the transaction and retain evidence of the checks completed.
VSiD’s approach connects the signature with the verified identity behind it. Relevant workflows can combine identity document authentication, biometric verification and evidential records with the electronic signing process.
Which type of digital signature should you use?
Choosing the right type of digital signature should start with the transaction, not the technology.
A routine internal approval does not carry the same risk as a property transaction, loan agreement or regulated customer onboarding process. Applying the same level of authentication to every document can either leave important transactions under-protected or make everyday processes unnecessarily difficult.
First, consider the value and consequences of the transaction. A document involving a significant financial commitment, transfer of ownership or regulatory obligation is likely to justify stronger controls.
You should then decide how confidently the signer needs to be identified. Email or mobile access may be enough for an established employee approving an internal document. A new customer completing a regulated transaction may need to provide government-issued ID and complete biometric verification.
The applicable legal and regulatory requirements must also be considered. Some documents require a witness, specific wording, an approved signing process, or evidence another organisation can rely on.
Think about what you may need to demonstrate later. Can you show who received the document, how they authenticated, when they signed and whether the document changed? If a regulator, bank, insurer or another relying party asks for evidence, will the available record be sufficient?
The signing process should also fit the wider workflow. If identity checks, KYC, KYB, AML screening, or source-of-funds information are required, disconnected systems can leave evidence fragmented across providers.
Finally, consider the experience for the signer. Strong security doesn’t have to mean a slow or confusing process. The aim is to apply the right checks at the right point without adding steps that are irrelevant to the transaction.
Digital signature uses by industry
Legal practices use electronic and digital signatures for engagement letters, commercial agreements, claims documentation and client onboarding. Stronger authentication can help connect signed documents with verified client identities and the due diligence completed at the start of a matter.
Property and conveyancing transactions can require specialist workflows around identity, signatures, witnessing and HM Land Registry requirements. These processes may need a higher level of assurance and evidence than a standard commercial agreement.
Financial services organisations use electronic signatures for account opening, loan documents, financial agreements and customer onboarding. Linking the signature to KYC, KYB, AML, and source-of-funds checks can provide a more complete view of the customer and transaction.
Claims and insurance teams may use them for consent forms, policy agreements, claims documentation and settlement processes. Where claims are handled remotely or at high volume, consistent identity and signing controls can help reduce risk without creating unnecessary delays.
Local authorities and public services can use electronic signatures for formal agreements, approvals, document exchange and other processes that require reliable long-term records.
Across general business, electronic signatures can streamline employment documentation, procurement, supplier contracts, sales agreements, non-disclosure agreements and internal approvals. Different departments may require different signature levels depending on the documents they handle.
Managing different signature types through VSiD OneConnect
VSiD OneConnect brings electronic signatures, secure document exchange, identity verification and digital onboarding workflows into one connected platform.
SmartSign provides eSignature and document exchange for organisations that need to send, manage and complete documents electronically.
SmartComply combines eSignature capability with identity verification and compliant onboarding. It is designed for transactions where the organisation needs stronger evidence about the person behind the signature.
SmartConvey extends these capabilities with specialist eWitnessing and HM Land Registry SmartForms for property and conveyancing workflows.
This structure lets you apply an appropriate process across departments. A team completing routine documents can use a straightforward signing journey, while a regulated or property-focused team can use stronger identity checks and specialist workflow controls.
Keeping these activities within OneConnect also creates a more consistent source of information across the customer and transaction journey. Documents, signatures, identity evidence and onboarding activity do not have to remain separated between several unrelated providers.
The result is a connected process designed to help your organisation sign documents, identify the people behind them and retain evidence that can be verified when needed.
Book a VSiD OneConnect demonstration to discuss the right electronic signature and identity verification workflow for your organisation.
This article was submitted by VSiD as part of an advertising agreement with Today’s Conveyancer. The views expressed in this article are those of the advertiser and not those of Today’s Conveyancer.
