I sent my self-assessment tax return through CalCal. My mortgage advisor / bank need me to send proof of earnings. They sent me a form to send to my accountant so it can be stamped.
Since CalCal are not acting as your accountants, we won’t be able to fill in the Accountant Reference. You submitted your tax return yourself, so we cannot verify the figures on it. However, you can download your SA302 by logging into CalCal and selecting the applicable tax year. There you should see two tabs – ‘Calculation’ and ‘Tax Return’. At the bottom there is a download button. The Calculation tab will give you your SA302 with proof of submission, and the Tax Return tab will give you the standard filled in Self-Assessment forms as you submitted them. In most cases these are sufficient proof of submission.