The Spamhaus Project


Email frequency and engagement

Here's our guide to email frequency & engagement, helping you understand how often to email contacts and keep them engaged for email deliverability.

by The Spamhaus TeamFebruary 15, 20224 minutes reading time

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Email frequency and engagement are elements that can’t be overlooked if you want to ensure good email deliverability. Setting recipient expectations during your confirmation message is a helpful strategy; sticking to that expectation is invaluable. Sending email too frequently can cause “email exhaustion”; people who have a clear expectation that is met will feel respected and are much less likely to report as spam, delete the emails unread, or unsubscribe.### How often should you send to your mailing list?

Marketers should tailor the “correct” frequency to the individual marketing campaign, and having a sunset strategy is vital to maintaining a healthy and engaged mailing list. Here is an example:

  • If more than a week passes without the recipient opening an email, change them from weekly to monthly.
  • If more than a month passes without the recipient opening an email, send them an email asking, “Do you wish to continue your subscription?” This should contain a link that the contact can click if they wish to continue.
  • If they don’t respond, add them to your suppression list and stop sending them emails!
  • Sending email in bulk to addresses that have never given consent to receive those messages is spam. Continually sending to email addresses that have never successfully been delivered is also spam.

Considering changing the frequency of your marketing emails?

Intended changes in frequency to email campaigns should be very carefully considered, especially around the holidays.

Many marketers believe that ISPs, reputation, and filter vendors such as Spamhaus “tighten the rules” around the holidays, which is not the case. Nothing changes on the recipient or vendor side – what causes the perceived “tightening” is created by changes in sender behavior.

The holidays are when senders tend to reach deeply into their subscriber lists (or even buy lists!), taking chances on sending to unengaged or even unsubscribed customers in the hopes of making some extra money during the lucrative holiday sales season. What usually happens is that using those older, unused segments triggers the domino effect of a decline in reputation. Then inbox placement is affected, leading to adverse outcomes, including tempfails, deferrals, blocks, and sometimes even inclusion on reputation lists, such as Spamhaus produces.

The value of email engagement

Engagement is valuable for measuring how your marketing program is performing and is typically measured by recording clicks, opens, purchases, and interactions with social media. If engagement is too low, it is time to look at the age, content, mailing frequency, and segmentation of the program lists.

Please note – Spamhaus reserves the right to engage with the spam we receive and even to follow non-subscription links. There are many anti-spam appliances that now do this also. The fact that an email is opened or a link is clicked does not mean consent has been given.

How often should you review email engagement?

We strongly recommend that you carry out continuous iterative work to segment out anyone that has not actively engaged with a given mail stream in X amount of time. The usual starting place is one year, then moving to six months, three months, etc., depending on results.

The importance of good email data hygiene

Remember – keep it clean! The regular practice of data hygiene is crucial: flawed address collection processes and bad sending practices can result in you adding spamtraps to your mailing lists. The presence of spamtraps confirms the underlying data problems; focusing on finding and removing traps treats the symptom, not the problem. Spamtrap hunting is a short-term solution with limited benefits, as traps are only one part of the reputational mix that is in use today.

Here are other mistakes that can be exceptionally costly in both time and money.

  • Sending to the “wrong” segment of a database, including failing to use your suppression list,
  • Making sudden sizeable changes to the volume or frequency of email streams.
  • Sending to older lists that may contain spamtraps or many invalid addresses,
  • Using a purchased list

Keeping recipients engaged and active is the single most important thing a marketer can do to ensure the success of an email marketing program. Reputation is much harder to rebuild than ruin.

Part of keeping that good reputation intact is effectively managing bounced emails and we’ll be explaining how to do this next.