Inbox timing: A critical component of e-mail relevance

Forget all the claims that one day or time is better than another to send messages to your mailing list. The ideal time to send e-mails, of course, is when each recipient is most likely to open and act on your e-mails.

Consider the four variables that factor into finding this sending-time sweet spot. They are demographics, time, mindshare and delivery time.

Suppose you market largely to women. Women who work in an office might act on e-mails at different times than stay-at-home moms. Unless you are capturing detailed demographics, you won't be able to optimally time e-mails to your female targets.

Time variables are endless. You have seven days, 24 hours and six time zones for US marketers, and up to 40 time zones around the world for global marketers.

Being the top of an inbox is critical, but the increased use of social networks and services like Twitter adds competition.

You send at 9 am on a Monday morning. However, the ISPs you send to can delay delivering your messages for an hour or even a day, depending on factors such as sender reputation.

Here are four steps to help you your ideal send time:

Track the time it takes your messages to reach the inbox. Use "seed" addresses within your mailing list to determine the average time between hitting the send button and when e-mails actually arrive in recipients' inboxes.

Monitor the times recipients open and act on your messages, including both broadcast and triggered e-mails such as confirmations, reminders and notifications. This isn't a perfect measure, because it will not capture open times by recipients who open them on mobile devices like smartphones or who open messages without downloading images. However, it should give you enough data to show you the trend.

Use open and click data to schedule message delivery. For more precision, you can segment deliveries if your data shows more than one major opening time. If you have captured geographic data, consider further optimizing by segmenting based on time zone. Sending based on an individual's open and click history is even better. One Silverpop client, Encyclopædia Britannica, used this technique in e-mail to split tests, resulting in a 40% increase in campaign revenue.

Use more trigger-based e-mails. These are more relevant to your subscribers because they arrive in a recipient's inbox based on an action such as a purchase or abandoning a shopping cart.

Loren McDonald is VP of industry relations at Silverpop. Reach him at lmcdonald@silverpop.com.