3D Secure is a security protocol used by banks worldwide to authenticate online card transactions. You can recognise 3D Secure merchants by Mastercard^® Securecode, Verified by Visa and American Express SafeKey logos on the online merchant's website.

3D Secure provides an added layer of security by prompting you for a OTP when you make an online purchase. This helps to protect against online fraud by verifying that the customer making the online purchase is the rightful owner of the credit card.

No enrolment is required as all Cardmembers are automatically enrolled. Please ensure that you have updated your latest mobile phone number with us as the OTP will be sent to the mobile phone number in our records.

No. The OTP is only required for online merchants that support the 3D Secure authentication protocol.

You will not be able to complete the transaction and will be routed back to the merchant website.

You will still be able to transact at 3D Secure merchant websites even without entering a OTP. However, this is not advisable as the transaction will be non-authenticated. Hence you are encouraged to update your mobile phone number with us. Simply call our 24-hr CitiPhone Banking at 6225 5225 to update your mobile phone number.