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A suppression list is a list of contacts that are not used for sending email marketing messages and newsletters. A suppression list is a default feature in each email marketing tools and helps comply with the CAN-SPAM Act.
A suppress list is often one single list over a complete email environment. But it is not just unsubscribed email addreses.

Suppresion List Categories

Your suppression List may contain the following categories of contacts:

  • Bounce – email address considered undeliverable after three attempts which resulted in soft bounces
  • Hard bounce – undeliverable email addresses
  • Unsubscribed – unsubscribed contacts
  • SPAM – contacts that reported your message as SPAM (gathered from FBL integrations with major ISPs )
  • Uploaded – those directly uploaded into a Suppressed list by you (when new customers migrate to us from other ESPs)

In starting with a new email service it’s highly recommended to upload your current suppressed contacts into your Suppressed List. If you do this during migration you avoid sending of unwanted messages.

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How To Use List Suppression Management Effectively

Suppression lists can be leveraged for a wide variety of marketing activities that go far beyond compliance with CAN-SPAM and other email rules. Many creative email marketers use suppression file management as a part of their overall audience targeting process. There are any number of instances where de-targeting or negatively targeting an audience group from a larger audience list may be more efficiently handled through suppression files rather than positive targeting.

An example of this outside the email space is the way that negative keywords are used in search marketing. They can be used to actively remove certain potential recipients from being targeted in a campaign.  

While there are any number of ways that suppression files can be used to optimize targeting and campaign performance

Removing Contacts from a Suppression List

As an marketer you can move contacts freely across all lists and segments. But often not to remove them from a Suppression List. For your own safety!

Why couldn’t you just move contacts from a suppress list to any active list? Because you have to respect every individual’s decision to subscribe to whatever source of information they want. It also makes it easier to be compliant with CAN SPAM Act. Similarly, uploading a list as “new”, should never be able to overwrite the earlier suppressed email addresses.

In case a contact wants to be removed from a Suppress List back to an active list, they will have to subscribe again. For instance using one of the Web forms you define.

In some cases, when you feel very strongly that a suppressed contact shouldn’t have been suppressed, a support ticket to the vendor will do the trick. Customer service at the ESP may move the contact back to an appropriate list.

Manually unsubscribing contacts and updating your suppression list.

A marketing or business owner may want to manually suppress certain email addresses from getting marketing materials.
Think about unwanted email subscribers like competitors, disgruntled ex-customers, known spammy domains / bots.

Depending on your email marketing tool, you could set up exclusion rules, upload a list or by navigating to that contacts profile page and pressing the “Unsubscribe” button.

Importance Of Customer Segmentation For Suppression List Management

Email marketers will often build a list for a specific campaign, by targeting specific recipients within their house files. This works well, as long as you are easily able to identify and select the specific audience segment to be targeted. If the segmentation is straightforward (select everyone who has bought a certain product previously) it may be relatively easy to pull that target group from the larger database.

However, if the target audience is based on an action not taken (every customer who did not buy a certain project) it may be more difficult to positively target that group. Instead, it may be much simpler to just create a file of purchases and suppress that from the larger list.

Similarly, if you are using affiliate marketers in your email programs, you might have an offer for a particular product or service that they are promoting through email. Instead of suppressing your entire current customer list, perhaps you only want to suppress any previous purchasers of the specific product in the new campaign. In this case, creating a suppression file of just this customer segment would achieve the goal of having affiliates focus on consumers who haven’t previously purchased the particular product they are marketing.

Really the only limits on this type of customer segmentation are based on your business and what data you have available about your current customers.


  • Dialing in your affiliates’ campaigns on the particular target audiences you want them to focus on.
  • The ability to more easily target and market to hard to identify audience segments on your customer lists.

What About Non-Responders

Over time, retention and acquisition email campaigns are mostly found to  include the same recipients in multiple campaigns. At a certain point – typically some number of contacts or a time period with no response – your analytics may tell you that it isn’t cost effective to continue mailing a recipient since they are highly unlikely to respond to further marketing. In these cases, you may want to build a list of the high volume non-responders and suppress them from future mailings – either your own internal mailings or those driven by affiliates or other outside mailers.

Removing this particular group of low value prospects may also deliver other benefits to your overall campaigns:

  • Mailing to a large number of non-responsive email addresses over time can have negative impacts on overall deliverability and sender reputation with different email platforms.
  • Removing these records from future mailings provides a cleaner list of more potentially responsive recipients. While email is a very cost-effective marketing channel, there are still higher costs to mail larger lists.
  • The incremental cost of adding one more address to an email campaign may be completely negligible, but once that number reaches thousands, tens of thousands or more, that cost becomes more of a factor.


  • Reducing email marketing costs by removing addresses of recipients who are highly unlikely to ever respond – and generate revenue.
  • Improving email campaign performance metrics like open rate, click rate, and conversion rate.
  • Having a positive impact on overall deliverability and sender reputation with email platforms.

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