E-Mail List Atrophy: The Effects of Old Addresses

Even as you read this, your email database’s value is shrinking.

Allow me to explain.

Many companies collect customer and prospect email addresses as a matter of course. Most are careful to obtain permission to use those addresses for marketing purposes. They try to obtain as much demographic data as possible. Those addresses are added to the database… and there they remain.

This occurs even when a company runs multiple, ongoing campaigns. Smart marketers classify and segment users to send targeted offers and promotions. Unfortunately, this campaign-driven, target-oriented approach can lead to some addresses not receiving any messages for months, even years.

In the intervening period, a lot can happen to an address. That, in turn, substantially affects how messages are received, and how your company is perceived.

  • The address no longer exists. With luck the message bounces and you can remove it from the list. But there’s a catch: Though ISPs understand some bounces are inevitable, they increasingly view a high bounce rate as a sign of spam and respond accordingly.

    In other words, a high bounce rate can get you filtered. AOL, for example, requires senders to maintain a bounce rate under 10 percent. Almost any list over a year old will fail that test.

  • The address is redirected. There are two common situations in which this happens. When an employee leaves a company, her email is frequently routed to another employee to ensure a clean handover. If you send a marketing message to that address a year later, the new recipient may report it as spam.

    In the public space, when an email account is cancelled, the associated address becomes free and can be picked up by someone else following a grace period (the average is three to six months). If you send an email to this address, the new address owner may complain the message is unsolicited as he didn’t sign up for it.

  • It’s become a spam trap. In extreme cases, old addresses are turned into spam traps. I’ve seen legitimately obtained single addresses, even entire domains, become spam traps by the time a company starts sending email. Hitting such an address can impact deliverability immediately and result in irritated calls from your email service provider.
  • The recipient doesn’t recall opting in. A recipient who checked “Send me exciting new offers and promotions” while registering on your Web site 18 months ago may not remember doing so when that exciting new offer finally arrives. Registering on a Web site isn’t a particularly memorable event for most people. The situation becomes far worse if the recipient checked “Have your valued partners send me exciting new offers and promotions.”

    If you follow email best practices, you can demonstrate to that recipient she did opt in. Often, the complaint will already have been used as a ground for other ISPs or domains to refuse your email.

The net result is old lists generate more complaints and lead to more blacklisting and filtering than newer or better maintained ones.

Some immediate steps to take to minimize both list atrophy and the imppact of old addresses:

  • Use an email change of address (ECOA) service. E-mail address churn is comparable to physical address churn, around 30 percent per annum. As with physical addresses, you can run email addresses through a COA provider. ECOA is much less established than physical COA, making it less effective. Yet it can certainly help recover some addresses that would otherwise be lost. Charges are typically per address corrected.

  • Manage bounces. Good bounce management is essential. Verify your system processes all bounces and doesn’t discard any as unidentifiable. Insure you are suppressing addresses that consistently bounce, even if the bounce appears to be a “soft” bounce. (define).
  • Facilitate address correction. It’s not uncommon for an old address to be forwarded to a new one during a transitional period. Make it easy for subscribers to update their email addresses (and, ideally, any other profile attributes) with every message you send.
  • Prevention is the best cure. Above all, maintain permission. Keep records of the last time each address was contacted, and send a message at least twice a year to recipients who haven’t received any other mailings.

    If you don’t have anything interesting to say, send a simple notification reminding recipients they’re registered to receive email from you. Tell them how, when, and where they came to be registered. Allow them to view and update profile and subscription options.

These important housekeeping duties go a long way toward keeping your list fresh and active. Recipients will thank you, ISPs will let your email get through, and your employer will thank you for improved response rates and higher return on investment.

Next, what to do when your list contains some older addresses.

Want more email marketing information? ClickZ E-Mail Reference is an archive of all our email columns, organized by topic.

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