What do I need to indicate in the payment reference? CardUp Team May 31, 2021 03:12 You would need to input the following on the payment reference field : Loan Policy Number Full Name Related articles What supporting document would I need to upload? How do mortgage payments work on CardUp? How would the recipient know that I have paid my mortgage payment via CardUp? Will my mortgage payments earn rewards on my card? Are there any credit cards that cannot be used for mortgage payments?