An email hosting service is an Internet hosting service that runs email servers.

Email hosting services usually offer premium email at a cost as opposed to advertising supported free email or free webmail. Email hosting services thus differ from typical end-user email providers such as webmail sites. They cater mostly to demanding email users and Small and Mid Size (SME) businesses, while larger enterprises usually run their own email hosting service. Email hosting providers allow for premium email services along with custom configurations and large number of accounts. In addition, hosting providers manage user's own domain name, including any email authentication scheme that the domain owner wishes to enforce in order to convey the meaning that using a specific domain name identifies and qualifies email senders.

Most email hosting providers offer advanced premium email solutions hosted on dedicated custom email platforms. The technology and offerings of different email hosting providers can therefore vary with different needs. Email offered by most webhosting companies is usually more basic standardized POP3 based email and webmail based on open source webmail applications like Horde or Squirrelmail. Almost all webhosting providers offer standard basic email while not all email hosting providers offer webhosting.

Implementation

For a technical overview of how email hosting services are engineered you can read about email hubs.