Email List Hygiene

How to Identify Inactive and Unengaged Subscribers

minute read

One of the most common recommendations I give to marketers is to keep their subscriber list file clean of inactive and unengaged subscribers. We have all heard or read about the pitfalls of sending to a large number of inactive subscribers: poor sending reputation, decreased inbox placement, decreased engagement and a decrease in revenue from the email channel. It can be a difficult problem to solve.  But, it can be solved through proper use of email intelligence and a simple spreadsheet.

An effective way to determine when a subscriber becomes inactive is to use a “recency” or time based method. A “recency” or time based method looks at the last date that a subscriber interacted (activity) with your email program or your business and compares engagement metrics, complaints and unsubscribe requests to determine the time frame that subscribers start to lose interest or become disengaged.

Step 1: Define what an “activity” is to your business

Activity may mean different things to different businesses so think about activities that are most important to meeting your business goals. Understanding how and when a subscriber interacts with you helps to tell a story about their lifecycle in relation to your business. Use as many of these metrics as you can in your analysis to help you get a full picture of their behavior.

For example:

  • Date of subscription
  • Date of the last email read
  • Date of last purchase
  • Date of last visit to your website
  • Date of the last account login
  • Date of last download
  • Date of last conference or seminar attended

Step 2: Create recency segments based on the frequency at which you mail your subscribers

A recency segment is a period of time that you measure an activity as you defined in Step 1. Be sure to consider how often you send email when creating a recency segment. Daily senders will generally have shorter recency segments than a weekly or monthly sender.

For example:

  • Daily Sender: 0-30 days, 2-5 months, 6-9 months
  • Weekly Sender: 0-60 days, 3-7 months, 8-12 months
  • Monthly sender: 0-90 days, 4-8 months, 9-14 months

Daily senders may also want a more granular look at activity levels on a monthly basis for the first 6 months and use 3-month windows after the 6th month.

Step 3: Create a simple spreadsheet to record and analyze your data

Using the recency segments created in Step 2, insert them in to a spreadsheet along with the engagement or activity metrics defined in Step 1. Insert the rate for each metric for each recency segment and look for the time periods when engagement levels begin to decrease and metrics like complaints and unsubscribe requests increase. Perform an analysis using several different recency segment ranges to help in your analysis (e.g. 0-15 days, 16-60 days, 3-6 months, 7-10 months). Also be sure to consider your sales cycle and seasonal fluctuations as they apply to your business.

In the example below, you can see that around months 5-6, the read rate and average order value decrease significantly while the complaint rate and unsubscribe rate increase.

Step 4: Send a win-back campaign or remove the subscribers

Once you have determined the time frame that subscribers start to lose interest in your email program you have a couple of options for the next step.

  • Send a win-back campaign: A win-back campaign reminds subscribers about the benefits of your program and asks them to re-engage. Subscribers that don’t re-engage should be suppressed from future mailings. Offer incentives such as product or service discounts to encourage retention.
  • Remove or suppress the subscriber: Stop sending to the higher risk inactive subscriber segments once you determine when they stop interacting with your email program. This option is aggressive but may have a more immediate impact to improving inbox placement and engagement.

As with any recommendation, be sure to perform the analysis and test different recency segments, timing and messaging to determine what works best for your business. Over time you will learn how best to keep your subscribers engaged and by keeping your subscriber list file full of engaged subscribers, improved inbox placement and increased email ROI are sure to follow.