For E-Mail Marketing, What's the Best Day?

For E-Mail Marketing, What's the Best Day?: "For E-Mail Marketing, What's the Best Day?
Published: September 27, 2005
(After October 05, 2005, this article will only be available to eStat Database subscribers.)

Monday has been thought to be the optimum day for commercial e-mail messages, but a new study says that might not be so.
Last year, two separate studies found that Monday was probably the best day to send commercial e-mail. Return Path found that e-mails sent on Monday had delivery rates markedly above average. The delivery rate on Friday was slightly below average, while the Saturday and Sunday rates were significantly below. Saturday was the worst day to send an e-mail in terms of delivery rate.
Another study, this one conducted by eROI, suggested that not only delivery rates, but also open and clickthrough rates were better on Mondays.
But a new report by ExactTarget asserts that there is no 'best day' to send commercial e-mails. If anything, the latter part of the week may be better. According to ExactTarget data, over 97% of campaigns are sent Monday through Friday. Wednesday is the peak day. "