You might remember I am a big fan of birthday emails because they can drive revenue and branding and build engagement with your subscribers for relatively little effort.

This year my birthday yielded 16 commercial email greetings plus one reminder (view screenshots of the emails on SlideShare). Not bad, but as I subscribe to more than 100 email programs from consumer brands, I was surprised at how few are taking advantage of the benefits this little goodwill ambassador can provide.

Below are my observations with this year's crop of birthday greetings:

1. Timeliness: Birthday Month vs. Day
Here's the delivery schedule for my birthday (March 16) emails:

Day 1 of the month: 4

Day 2-10: 6

Day before: 1

On birthday: 5

Post-birthday: 1

An emerging trend among consumer brands is to batch birthday emails for all subscribers born in that month and send on the first day or early in the month. With this approach, you can create unique creative and offers for one-twelfth of your database and have the promotions run for the entire month.

Among my birthday emails, the monthly senders used copy and a nonspecific subject line to convey that the wish was for the whole month.