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Nov 28, 2011 | 6 minute read

How to Reengage Inactive Email Subscribers

written by Linda Bustos

Inactive email subscribers. The ones that you mail, mail and mail again for months or years, and never an open, never a click. Removing them can help your sender reputation, as too many inactives can be a flag to ISPs and hurt your overall delivery percentage. But cutting them off prematurely could mean lost future revenue. What should you do?

The rules of engagement

ISPs track both positive and negative engagement activities which can impact your deliverability. Positive engagement

  • Clicking through links
  • Adding an address to safe list or address book
  • Turning images on
  • Opening the message
  • Scrolling through the message

Negative engagement

  • Reporting as spam
  • Deleting without reading
  • Moving to trash
  • Marking as read
  • Ignoring (no action taken)

Source: Responsys Email Engagement Study, 2011Measuring clicks is the most accurate way to determine engagement, as open rates are not fully accurate due to image suppression and preview panes. And clicking something suggests the content was interesting enough to spur action. (Another reason why you should never send a retail email that doesn’t have a clearly clickable call to action). Notice that clicking an unsubscribe link appears on neither list, so it’s a better idea to make it easy for a user to unsubscribe than to minimize this call to action in hopes nobody opts out. If anything, the click to your unsubscribe page or “update your preferences” is a sign of positive engagement – even if that subscriber ultimately drops off.

Inactive subscribers defined

We see there are a number of signals that indicate an uninterested subscriber, but how long they have gone cold is important, yet variable. ISPs will tolerate 18-24 months of inactivity, but your own analytics may reveal a tighter window. Segmenting the disengaged from the engaged and testing frequency, offers and time of day along with a re-engagement campaign can help you determine the tipping point. “In tests that we’ve done with clients, the vast majority of reactivated subscribers were inactive for less than 18 months,” says Responsys’ research report, which includes a case study where the optimal engagement window was half that, at 9 months. Also note, there’s a difference between an inactive email subscriber and an inactive customeror “lapsed buyer.”

Are inactives unvaluable?

The Smart Insights Digital Marketing recently posted an article by Dela Quist of Alchemy Worx, who offered 5 reasons why an email subscriber might be inactive.

1. They want your email, but haven’t needed your product for a while. 2. You’re receiving false negatives – your email is optimized to be read with image blocking on, so some subscribers could be opening it without you knowing. 3. The subscriber doesn’t want your email, but doesn’t care enough to unsubscribe. 4. Email address churn – the subscriber no longer uses or rarely checks that email address. 5. They don’t see your email because it goes into the junk folder. By far the largest group is the first one – we call these people the unemotionally subscribed. They will happily ignore your emails until they’re ready to buy, because it’s easier than unsubscribing and having to remember your URL or Google you later. We’ve gathered plenty of evidence on this group and demonstrated that while they might not read an email, they’re still a very important customer base. For example: • One of our clients generated $120,000 from subscribers who had not opened or clicked on the previous 25 to 40 emails. • Another saw 14% of revenue generated by subscribers who did not open or click a single email.” Common marketing advice would have been to delete those subscribers after a year’s inactivity. But by retaining unemotionally subscribed addresses, the client brought in a significant amount of additional revenue.

Inactive subscribers can become customers, so the answer is to make efforts to reengage the subscriber before removing them.

Reengagement strategies

Reduce frequency

Responsys recently completed a 3+ year experiment, subscribing to 100 retail email lists using fictional personas. Testers opened and clicked regularly for a period and then stopped. After 40 months, 31% were still mailing at full-throttle frequency, while 23% reduced frequency, 14% had stopped, and the remaining 32% stopped mailing after reducing frequency.

Sending inactives email less often reduces your overall negative engagement scores with your ISP. It also allows you to see if engagement improves among this segment simply by appearing in their inbox less. Don’t wait until subscribers are inactive for 18 months – by then, chances are you’ve already lost them. 3, 6 or 9 month windows are a good place to start. Your goal is to re-engage them and move them back in your actives file.

Mix up the content

So you’ve reduced frequency, but how do you determine which campaigns to send and which to suppress? These are a few of Responsys’ tips:

1. Send only your best offers and deals.

2. Send exclusive offers to this segment.

3. Test different subject lines (with trigger words like “come back” or “we miss you”) If reengagement doesn’t work, remove the subscriber after 24 months (your ISP’s threshold). You may lose some “false negatives” that never turned their images on, but if they haven’t clicked, you’re better off cutting them loose.

Additional tips to protect sender reputation

Build up your positive engagement signals, and reduce your negatives with these best practices:

1. Have a clear call to action in every email. And make your links / buttons / banners look clickable. I’ve said it before, and again, and now I’m saying it…again.

2. Send welcome emails that ask customers to update preferences and add your sender name to their address books / safe lists. (Hey, while you’re add it, why not segment out subscribers who don’t engage with your welcome email and keep these items prominent until they do?)

3. Design for images off, with enough teaser text that subscribers are motivated to turn their images on, and ultimately, click something.

4. Test headlines and always be closing testing better headlines! Learn what wins an open and what gets ignored, on average, over time, and to various segements.

5. Segment!!!!! Yes, I’m yelling. Find useful ways to better target offers so that your campaigns are as relevant as possible. I’ll get you started…segment by geography and exclude non-US residents and do not send them Turkey Day mailings in November.

6. User test creative to find out what compels people to scroll. It’s a sign of engagement.

7. Clicks are the most important engagement signal. Did I mention make things look clickable? Even if you’re only directing people to visit you at a physical store, give them something to click and ask them to click it. How about social sharing links if you’re stuck for ideas?

8. Research shows people often misuse the report spam button, simply to indicate they are not interested in a particluar email (even if they opted in to your list!). First, allow subscribers to provide feedbackon their interest level in your campaign:

Second, make your unsubscribe link uber-prominent (at the top of the page and the bottom) so the no-longer-interested can stop mailings without hurting your sender rep.

9. Have a preference center, and periodically include a call-to-update in your campaigns. There’s pros and cons to asking for preferences upon sign up – the extra questions may reduce your conversion rate, but it gives you much better targeting afterward. Someone who takes the effort to fill out a longer form is more likely to want to hear from you anyway.

10. Pick your sender name with care. Nondescript ones like “nobody” or XYZ are not going to stand out when users scan their inboxes. And don’t switch your sender name frivolously. You’ll mess up the “safe” lists of your existing subscribers and potentially confuse them to boot.