You can add text to the footer of your fundraising website.

This is an area where you could include information like your nonprofit's address, Tax ID number, copyright/trademark information, email or other contact information, links to your main website, etc. 

To add your custom footer, go to Website Options >> Basic Info, then scroll to the Custom Footer field. 

You are limited to 350 characters, including links. When you save the custom footer, it will appear at the bottom of the donation website on all pages.