A method of advertising via e-mail whereby the recipient of the advertisement has consented to receive it. This method is one of several developed by marketers to eliminate the disadvantages of e-mail marketing. If opt-in e-mail advertising is used, the material that is e-mailed to consumers will be "anticipated". It is assumed that the consumer wants to receive it, which makes it unlike unsolicited advertisements sent to the consumer. Ideally, opt-in e-mail advertisements will be more personal and relevant to the consumer than untargeted advertisements.
Opt-in email advertising differs from email campaigns in that it is usually a "canned" format with a short message sent only once. This format benefits consumers in that they receive only relevant offers from known sources, while vendors benefit from email advertising through the addition of a low-cost "pre-qualified" distribution channel, givin email advertising an ROI advantage.