You can determine what appears on the footer of your invoices in Settings -> Invoice -> Layout

If you're using Stripe to take payment you can add something like: 

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You can pay your invoice online by clicking on the link below:

##PAY_INVOICE_BUTTON##

Alternatively, please pay via BACS, as below:

Account Name: Your Practice
Sort Code: 00-00-00
Account Number: 12345678

Payment terms are strictly 30 days

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which would appear on your invoices like this:

Published on: 25 / 11 / 2020