I know statistics can be a royal bore, but there’s this one piece of statistical information you really should pay attention to — your email campaign bounce rates.

Regardless of which Email Service Provider (ESP) you’re using, you should be able to see bounces. Ideally, you’d like to see them at zero, but realistically, if you try to keep them to a minimum, say 1-2%, you should be OK. If you are 5% or more, and your list is in the thousands and/or you send emails frequently, you may be digging a hole for your email campaigns.

You may think this is not a big deal, but it actually is very much so. Big ISPs such as Yahoo, AOL, Sympatico may label you as a spammer if you repeatedly try sending emails to non-existing (expired, mistyped, etc) addresses. This is because it may appear to them as a typical spammer practice of “dictionary attacks”.

Those bounced email addresses are “dead meat” and should be removed promptly. Sometimes your ESP may give you false positives, so generally you don’t want to remove an address the first time it bounces, but after the second or third time it’s probably safe to assume the address is no longer active and should be removed, or at least moved to a separate list.

If you normally send HTML emails, you may want to try sending a text-only version to see if you can get through to some of those bounced email addresses. Simply move (or segment) all your blocked addresses to a new list then mark all of these as “text-only”. Next time you send a promotion these contacts will only receive a text-only email – this may be enough to bypass their ISP’s spam filters (some block all HTML email). If they still bounce, they are history.

If you have resources available, you can have staff or a VA go over the bounces and check for spelling errors, obvious typos (simpatico vs. sympatico, or aolcom vs. aol.com, yahoo!.com vs. yahoo.com) and other ways of identifying the errors.

If the address appears valid, and you see it belongs to an active client, you may want to contact them by conventional means (postal mail, phone, fax) to check if they’ve moved and changed email addresses. All these can be automated to some extent (e.g. voice mail broadcast).

Your email marketing list is an important business asset and should be tended to on a regular basis.