Are your subscribers as active as they could be? Read on as we show you how to identify who's still paying attention, use re-engagement techniques for those who aren’t, and improve the relationship you have with the people on your lists.

All email marketers have inactive subscribers who haunt lists and well, cost money with seemingly little return. But unlike “Bounced” emails - where the message is clear that the email addresses are not valid - having a subscriber with no opens recorded can mean so many things. Regardless of the reasons for staying quiet, having too many subscribers not engaging with your campaigns, that is, opening, clicking and more - can be costly, and affect your deliverability over time.

Conversely, engaged lists mean better inbox placement and return on your email spend (ROI). Let's walk through how to measure engagement, how engagement affects deliverability and ROI, and how to create a re-engagement campaign.

How engaged are your subscriber lists?

Good email marketing is about sending high quality content to a list of people who have chosen to receive content from you. 'Engagement’ is its measure. Most frequently, it's represented by the ratio of opens and clicks over a period of time.

We took a look at 18,000 active subscriber lists (being those that were used to send a campaign in 2013) and categorized them with a couple of novel names, to help you identify different levels of engagement in your own lists. Note that subscribers who had not been sent a campaign yet were not included:

Category Open and/or Click frequency % in average subscriber list
Very Active 2+ times in the past 90 days 3.28%
Active At least once in the past 30 days 21.24%
Engaged At least once in the past 90 days 11.74%
Unengaged None in the last 90 - 180 Days 9.77%
Dormant None in the last 180+ days 3.81%
Zombies None in the last 12+ months / Never 40.16%

It's pretty shocking to see that on average, 40% of subscribers can be classed as "Zombies", that is, they're perpetually unengaged - likely because they've abandoned their email address, left a job or filter their mail overzealously. While this is concerning, it also means that there's a lot of room to improve your engagement rates - and your return on email spend (ROI) and delivery rates in the process.

Getting more value from your campaigns

The link between having list engagement and ROI is fairly straightforward. An engaged list loves the content you're sending and as a result, opens, clicks and consequent visits to your site. So, what if you measured your list and have found it to be teeming with Zombies? It’s time to actively re-engage subscribers.

Using this 5-step re-engagement plan, you can get back into your subscribers' good books. It may seem like a little work, but as we'll be outlining in a not too distant blog post, the results can be totally worth it - with less money being spent on inactive subscribers, higher engagement and better deliverability.

Our 5 step re-engagement plan

Step 1 Go Zombie hunting
Identify any subscribers who haven’t opened one of your campaigns in 12 months (assuming you've sent a few in this time) - you can segment them using custom fields.

Step 2 Send a reconfirmation campaign
Put your best foot forward and send a “we want to make sure you still want to hear from us” -style reconfirmation campaign to these subscribers. For example, you can send a special promo, a thank you note, or actively ask for their feedback. Keep in mind this should be a pull-out-all-the-stops, best content, best offer kind of email, because this is the last chance you have to impress.

Step 3 Pat yourself on the back
Following the re-engagement campaign, it's time to turn to your reports. If a couple of subscribers have engaged with the email, well done - we'll hopefully see activity from them in the future.

Step 4 Say goodbye
If your Zombie subscribers don't open or click on the re-engagement campaign, it’s time to say goodbye. It may seem like you are getting rid of potential customers or "hard earned signups", but the reality is that they are likely doing more harm than good by hanging around.

While one benefit to cleaning up this group is that you are saving money by not sending to people who aren’t interested, the main upside is that you are removing the deadweight from affecting the performance of the rest of your list. The engagement level of your list as a whole will improve which should result in better inbox placement. That means your emails have a better chance of being seen by those who are interested in what you’ve got to say, which you should see reflected in your open and click through rates.

Step 5 Revisit your content
As they say, prevention is better than the cure - so it's time to up your game and give subscribers less reason to go quiet in the first place. In particular, the first 90 days following a sign up are critical, so it's very important to focus on whether you're communicating effectively with new subscribers in this courting period. Are you inviting them in, showing them around, making them feel comfortable and being a good host? Using autoresponders to send a welcome series of emails, or post-purchase follow-ups can automate this process, as well as be very effective.

Overall, there is absolutely no substitute for solid content. If you are sharing must-read news and articles or hey, the cutest puppies, your subscribers will want to open your emails.

Now, we'd love to hear from you - have you sent a re-engagement campaign? What has worked well for you? Share your story with us in the comments below.