SENDING DURATION EMAILS
Are you sending out 4,000 emails or 4 million? Depending on the technology solution or provider you use and volume being sent, it might take anywhere from a few minutes to many hours for your software or ASP solution provider to actually send the emails out to ISPs for delivery to the end recipient. Monitor and understand this duration period and make sure you factor it into your calculations.
Are you are using an ASP solution or sharing a mail server with others in your company? If so, keep in mind that when you've pressed the send button your emails will go "in the queue" to be sent. If you schedule them on a day and time such as Tuesday morning (when a large percentage of emails are sent), your emails may be in the queue behind many other companies or departments of your company, and may take longer than you anticipated before they
are actually sent. ACTION: Understand if the "queue factor" applies to you and add this estimated time into your calculations.
Not all ISPs are created equal. Some ISPs deliver emails they receive immediately, while others may take an hour or in some cases 12 or more hours to process emails. Secondly, some ISPs utilize volume-based filters, so sending too many emails to a single ISP within a short time frame may cause your emails to be blocked - and sent to the ISP blackhole. ACTION: Consider sending test emails to seed email accounts with ISPs such as AOL, Hotmail, Yahoo and others that comprise 5 percent or more of your list. If one or more consistently shows a significant delay in delivery, consider segmenting those subscribers out and scheduling them for an earlier delivery time.
For emails sent frequently (and the frequency is known and expected by recipients), then consistency is really more important than time of day or day of week. If you send a newsletter at least two-times per week, then sending at the same time for every newsletter is recommended. You want recipients to almost be able to set their watches by your emails. For example, two newsletters I've been receiving for a few years arrive at about 3:15 p.m. and 5 p.m respectively - times some would suggest are bad for email. But when my Outlook bell goes "ding" at about these times in the afternoon, I almost always check to see if it is one of these expected newsletters. For monthly newsletters and irregular ecommerce emails, a consistent day or time may be of little importance - but the right time/day could make a huge difference depending on the recipients' demographics and the nature of your content.