Is there a best time to send email?

According to KISSmetrics there is!  What is most interesting about their article though is that you have to balance 2 concerns.

1. While open rates are highest in the mornings (6am to 10am and on Weekends)
2. The highest abuse reports for email are also during those times (0.11% and 0.15%)

While the percentages for complaints of abuse are much smaller – keep in mind that most ESP providers will only allow for 0.01% of SPAM complaints before they will shut you down.  ESPs are required to comply with the anti-SPAM act so they will be unwilling to risk being blacklisted to accommodate your high SPAM complaint rates.

Read the full article here.