Login to Orchestra. From your 'shareholder summary' or 'option summary' click the button for 'Edit entity'.
If you have multiple entities to choose from then switch from your 'investment overview' to your 'entity overview' and click the entity you want to edit.
In the edit box update your email address in the 'Entity contact / communication email' field near the top. Click the 'Save' button.
Please note: Changing your entity email address does not change your user login email address. As your email address is your Orchestra username, to login using a new email address, please sign up again using your new email address. If you would like to close a user login that is no longer in use, please contact us from the email address on the account you would like to close.
Please see: How do I change my login email address?