How do I add a reference when paying with Siri?

When you ask Siri to make a payment, it will recognise certain words or phrases like ‘for’, ‘with reference’ and ‘with note’ to automatically add a reference.  

For example, if you’d like to add the reference ‘dinner’ to a payment, you can say "Siri, pay Mark twenty pounds for dinner."

You and the person you paid will see the payment reference when looking at the payment details.