We often live in mortal fear of overmailing our donors, especially email, which we can send without the cost limitations of postal mail. Surely, there's a point where you're sending so much email you become an annoying spammer. The DMA (UK) Email Marketing Blog looks at this questions at Maximising ROI without overmailing.
The post points out that there's not one "right" frequency of mailing for the entire file. Every email file has different groups that behave very differently from each other:
- 1 - 5% of the list open, click and buy almost every time they receive a message.
- 40 - 60% of the list will interact with the offer mailing once or twice a year.
- 35 - 55% of the people on the list will not have opened or clicked, let alone bought off an email you sent in over a year.
This insight -- that your file is not one monolithic group, all experiencing your messages in the same way -- frees you to be more relevant to more people: For the first group, you can probably send even more. For the second group, you're likely about right. For the third group, you're almost surely sending too much already.
And you'll know if you're getting it right because you're testing.