Frequently Asked Questions

General

How can I use Sign with Singpass?

Organisations (such as government agencies, financial institutions, and private businesses) who are integrated with our service can request for you to sign documents using your Singpass.

If the organization/application you are transacting with offers Sign with Singpass, you should see a button like this:

Sign with Singpass buttons

By clicking on it, you will be guided through the process of signing with your Singpass. See our guide on How to Sign.

Who can use Sign?

Anyone with the Singpass App can sign documents using Sign.

Both government agencies and private businesses can integrate with Sign. To join us as a digital signing partner, please visit the onboarding section.

Can I sign without a Singpass App?

No, you are required to have the Singpass App in order to sign documents.

What is the difference between Secure Electronic Signatures and Ordinary Electronic Signatures?

Ordinary Electronic Signatures (OES) is a broad category that refers to electronic signatures that are not SES.

Under Section 19 of the Electronic Transactions Act (2010), secure electronic signatures are accorded the following presumptions:

(a) the secure electronic signature is the signature of the person to whom it correlates; and

(b) the secure electronic signature was affixed by that person with the intention of signing or approving the electronic record.

Source

Authenticity

How to verify signatures?

Refer to this section on verifying signatures.

When I opened the document on Adobe PDF reader, it says that the signature is corrupted.

Refer to this section on verifying signatures. When downloading the document onto your device, please ensure that you do not have a firewall that is modifying the file in transit (content disarm and reconstruction), as that will affect the integrity of the signature.

"Certificate validity is unknown"?

If you see "Certificate validity is unknown", this is because you do not have the Singpass root signing certificate on your device. Please refer to this guide to install the Singpass root signing certificate.

If I delete my Singpass account, will my signature still be valid?

Yes, the signature will continue to be valid.

If the signer migrates, will the signature still be valid?

Yes. The document can be traced back to the signer.

How can I know if my signature is secure and protected?

Digital signatures rely on public-key cryptography, a method that uses a pair of keys:

• Private Key: A secret key known only to the signer. It is used to create the signature.

• Public Key: A key that is made publicly available through the Singpass signing certificate. It is used to verify the signature.

Private keys are stored securely on the Singpass mobile app and can only be accessed by the user.

Furthermore, it is computationally infeasible to replicate the cryptographic process (hashing and encryption) used to generate the signature.

Lastly, the signer's public key is validated by Singpass. Singpass verifies the identity of the signer and that the public key is associated with the correct person.

Can a document's details be altered after it is signed?

If there are unauthorised modifications to the document after it is signed, the digital signature will be invalid.

As digital signatures are cryptographically linked to the signed document through a hash, the hash value will change if there are unauthorised modifications to the document after signing, and the signature will be deemed to be invalid.

Others

Is there any cost to using Sign with Singpass?

Sign with Singpass is currently free of charge, both for organisations integrating with us, as well as for signers.

Can I sign from overseas?

As long as you have access to your Singpass App, you will be able to Sign with Singpass.

If you have a question and are unable to find an answer in this FAQ, please submit your question on our Singpass Q&A site to seek further assistance.