The biggest advantage of a domain-based email account is that it delivers a professional touch to all communications made from that email. A secondary advantage is that it spreads awareness of the domain, making it a brand-building tool for businesses of all sizes.
A domain-based email account, as opposed to a generic account through a free email domain or subdomain, shows an affiliation with the domain itself. This imparts a sense of professionalism and adds a layer of verification for recipients that a user sending an email from the domain is a part of the company or brand that owns the domain. GoDaddy advises that customers choose businesses with a professional email nine times more often. Their accounts also allow the creation of multiple alias emails to help simplify traffic to and from the email account.
A business can help promote its brand through the use of domain-based emails. Customers with emails coming directly from a business website domain may feel more secure working with the company, and the email exposes them to the name to reinforce the validity of the brand as well as the sender. Domain-based email accounts can also work the logo into the signature field of outgoing emails, providing further brand exposure.