As ISPs and hosted e-mail vendors try to protect their users from spam, they also block and filter legitimate commercial e-mail messages. A pair of recent studies, one from Lyris and the other from Return Path, measured deliverability rates for legitimate e-mail among different ISP and hosted e-mail providers.

According to Q1 2005 Lyris EmailAdvisor data, the average rate of legitimate commercial e-mail deliverability to user inboxes was 88.5 percent. That climbs a bit to 92.5 percent for average 'gross deliverability' of legitimate commercial e-mail. Lyris defines 'gross deliverability' as the total amount of e-mail delivered to both regular user inboxes and 'bulk' folders; 'inbox deliverability' refers to messages that make it directly to the inbox.

Commercial E-Mail Deliverability Rates Posted by: DTB at 9:51 PM  |  Permalink