If you’re just getting started, a free domain might be enough. Mailchimp’s free website builder includes a free Mailchimp-branded domain (like yoursitename.mailchimpsites.com), and that’s great for businesses that want to get up and running for as little cost as possible.
At some point, though, you might be ready to buy or connect a custom domain. These are domains like yourbusiness.com or yourcompany.net—addresses that don’t include builder brandings like yourbusiness.weebly.com, yourbusiness.wixsite.com, or yourbusiness.mailchimpsites.com. There’s nothing wrong with those branded domains, but custom domains can help you look more professional. Mailchimp offers custom domains starting at $12.99/year.
Keep in mind that some companies like Wix and Weebly don’t let you add a custom domain for free to a pre-built site. Mailchimp does.