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E-mail Marketing - The Right Audience

13 min read


E-mail Marketing - The Right Audience

The audience, also known as contact list, is one of the main subjects when it comes down to e-mail marketing campaigns. While you should have a strong focus on campaign results and high engagement rates, you will also need to pay close attention to your e-mail deliverability performance.

Mailbox providers (for example, gmail, outlook, yahoo) look for suspicious behaviors around your audience such as too many invalid addresses, low engagement from recipients, and the like. The right approach to build a healthy contact list is needed, if you want the e-mail to be delivered as well as placed in the user’s inbox.

In this article, we will share some best practices to build and manage a contact list considering aspects like engagement and compliance. 

Table of Contents


Despite all the great new channels, tactics and technology, e-mail marketing remains one of the main campaign tactics used in most countries around the globe. It is often an underestimated channel leading to an inefficient usage of it.

In the article Welcome to E-mail Marketing, we have already introduced you to the basics of e-mail marketing and briefly talked about the four aspects of becoming an e-mail deliverability hero:

  • Become a trusted sender
  • Use the right audience
  • Create relevant content
  • Be relevant

In this article, we want to dive deeper into the audience, also referred to as contact list, e-mail list, or target group. Building and maintaining a healthy contact list requires some effort and practice. We will share with you some best practices on how to build a healthy contact list. 

Build Your Contact List

Acquisition and Growth Strategy

It can be very tough to get started with e-mail marketing. Before even thinking about all the advice in this article, you will need to figure out one thing: Where do I get the e-mail addresses to send my messages to?

Some of you might be tempted to cut corners and buy e-mail lists. However, we have experienced heavy negative side effects by doing so. Next to potential legal issues (for example, General Data Protection Regulation), the risk of low quality lists and spam traps is huge. Spam traps will result in blocklisting and low quality addresses in high bounce rates. Even with the good quality addresses left, often the engagement rates of recipients are very low, and the complaint rates are high. This ultimately leads to a bad sender reputation and can destroy all of your e-mail marketing efforts.

Therefore, we always recommend you to go with an organic growth strategy and to rely on your own data sources for contact lists.

If you start from scratch, it is worthwhile to investigate all potential databases that might contain e-mails. Often, we see that agencies own those databases on behalf of our customers. You should pull all of those segregated sources into one place. It will not only make your e-mail marketing more effective, but also help you to stay legally compliant. SAP Marketing Cloud will help you from a technological standpoint to create the best record of your customer, but you will need to feed it accordingly.

If you find yourself in the situation where you start with zero e-mail addresses or you simply want to grow the existing contact list, you should start to ideate proper awareness campaigns. Our Campaign Ideation with Design Thinking approach may help.

Regardless where your e-mail addresses are coming from, they should follow best practices around permissions and list hygiene tactics.

Establish a Solid Opt-In Process and Management

image one: Example of a double opt-in process

In the e-mail opt-in process, it is possible to get explicit authorization from customers that they want to be reached out through e-mail. This is the main recommended practice when it comes down to building a contact list.

The process can be even better, if a double opt-in is in place. It doesn’t only collect the users consent, but also prevents from having bad addresses such as fake addresses, addresses with typos, and so on. This can prevent hard bounces and the risk of being blocklisted. Image one is highlighting a great example of a double opt-in process.

Provide an Easy Unsubscribe Process

You should provide your recipients the option to easily unsubscribe from any communication. The easier your process, the lower the chances will be that your recipients will raise a complaint within their mailbox provider (click on spam or click on complaint). As we have learned in the Welcome to E-mail Marketing article, complaints are toxic for the sender's reputation and should be prevented at all cost. Furthermore, some country regulations enforce using easy unsubscribe options.

image two: Example of a 'List-Unsubscribe' as shown in the mailbox provider Gmail

We recommend to go with two options to ease the process for your recipients:

  • List-Unsubscribe: As shown in image two, the unsubscribe option is shown very prominently in the e-mail header. This feature is defined by RFC2369 and needs to be supported by the mailbox provider (in our example Gmail) as well as the e-mail service provider (ESP). If you use SAP Marketing Cloud in combination with one of our default ESPs (Amazon Simple E-mail Service or SAP Digital Interconnect), you will be able to leverage it. However, not all mailbox providers support list-unsubscribe and therefore you should always go with the option 'unsubscribe in the HTML body' as described below.

  • Unsubscribe in the HTML Body: Add a link in the HTML body of your copy. As stated in our best practice article E-mail Marketing - The Content, you should work with templates and place the unsubscribe option prominently within those templates. SAP Marketing Cloud will give you the option to easily manage your templates as well as your unsubscribe links. In contrast to the recommended double opt-in process, you should consider using the single-step-process for the opt-out.

It is not a bad thing to make the opt-out process easier for users. Some marketers are afraid of adding or highlighting the unsubscribe button, but it is actually a good thing as the alternative for users who couldn't find the link is to just mark it as spam. The easier you make the process, the healthier your contact list will be. 

List Hygiene

Keep Addresses Valid

Your goal should always be to have lists with valid and engaged contacts. A key measure to achieve this is to have strict rules around invalid addresses to keep your bounce rates below 2%. Typically, we recommend you do three things:

  • Automated Hard-Bounce Handling: Keep the automated hard-bounce handling in the pre-configured state within SAP Marketing Cloud. It will automatically invalidate addresses that bounced hard and will prevent you from using them in the future. This measure will do all the work for you, as long as your sending pattern and your list growth rates do not change dramatically.

  • Pay Attention to Soft-Bounces: Soft-bounces are usually temporary by nature. At the time of writing, the ESPs that SAP Marketing Cloud integrates with (Amazon Simple E-mail Service and SAP Digital Interconnect) are handling them automatically by trying to resend the message. However, they will only attempt to resend the message over a certain period of time and then they will stop doing so. You should pay close attention to the soft-bounce rate and make sure that your campaign does not exceed the threshold of 2%. If it does, you will need to do an investigation to fix the problem. A very common reason for a soft-bounce peak is a sudden change of your sending pattern leading to a temporary loss of trust. If you plan to change your sending pattern dramatically, you should consider a warm-up exercise to prevent long-term damage to your reputation. Check the conclusion section below for deep-dive articles on how-to do a warm-up.

  • Pre-Bounce Checks: Run a pre-bounce-check on all new lists you want to introduce to your e-mail marketing process. You should never add a big list to your database and then simply execute on it, since it bears a high bounce risk and could heavily harm your reputation. We recommend using tools such as NeverBounce to clean-up invalid addresses and keep your bounce rate as low as possible.

image three: Screenshot from NeverBounce highlighting a hard-bounce analysis

A simple analysis with an indication on the bounce-rate can be done in the free version of NeverBounce as demonstrated in image three above. However, the actual clean-up on individual e-mail addresses requires a paid subscription. We strongly recommend you to have NeverBounce or similar tooling in place as part of your list hygiene tool box.

NeverBounce and SAP Marketing Cloud give you multiple options to use the pre-bounce-check service. The easiest one being a manual and file based approach. If you want to have a fully automated approach, you can follow our technical how-to guide here to make it happen.

Focus on the Most Active Users

image four: Screenshot from the segmentation app and the selected attribute for e-mail affinity

Another measure to achieve a healthy contact list, is to focus on the most active recipients. This is especially important during the IP and domain warm up process. As shown in image four, SAP Marketing Cloud is allowing you to build segments based on a score called e-mail affinity. It allows you to target contacts based on their level of engagement with e-mail campaigns. The engagement is measured by combining open and click rates as well as the marketing permission.

In addition, you should focus on recipients who have shown no activity (open) over a long period of time. We highly recommend to isolate those recipients. In a last attempt, the isolated list can then be re-engaged as described in the next section or simply sunsetted. To sunset means that you are taking them out of all active and future campaigns or that you fully delete them. You will need to do this manually, but SAP Marketing Cloud is helps you to easily identify those contacts with the segmentation app.

Many marketers have a hard time to sunset contacts from their lists. Therefore, keep in mind that those contacts have a zero return of investment, generate cost, and harm your reputation. There is really no reason to keep them in your active e-mail list.

Re-Engage Inactive Users

So, you went through the whole list hygiene process and found a second list with inactive or excluded recipients. This list could actually help you to increase your campaign reach and efficiency. What should you do?

We recommend you to run a specific re-engagement campaign and keep the recipients isolated until they become active or you sunset them. Ideally, you should follow the steps below to be successful:

  1. Do Not Use the Same IP or Domain, Use a Secondary IP and Domain Instead
    If you have a dedicated IP and domain with a good sender reputation, it's not a good idea to use it on a list full of inactive recipients. Chances are high that your engagement rate will be low and potentially the complaint rate might be higher than usual. All of the aforementioned factors will have a negative impact on IP and domain reputation. Therefore, we recommend to use a secondary, shared IP, for this specific campaign.

  2. Clean Up the List
    Make sure that the addresses are valid and do not bounce. Review the section above for instructions.

  3. Ramp Up the Number of E-mails Sent
    With any initial campaign setup, we recommend to start with a low number of e-mails to send out (something closer to 50) to warm up both IP and domain and to slowly increase it (growing around 3% every day) until the whole list is reached. Make sure to track the important KPIs (bounce rates, complaint rates, open and click rates) and act fast by adjusting the campaign, and reviewing the contact list. Basically, you run a small warm-up exercise for this campaign. Go the the conclusion section of this article to find the deep dive articles on warm-up.

  4. Focus on Content
    If you want to re-engage your user, the content selected should be simple and catchy. Make sure to build it with a strong grabber, a clear call to action and ask if the recipient wants to continue to communicate with you. 

By following the above steps, you will ensure that you don't put your current IP or domain at risk and that you keep your contact list highly active and engaged.


In this article, we shared best practices to build and maintain a healthy, clean and engaged contact list, thus improving the deliverability and also the inbox placement of e-mail campaigns. However, we are not done here. Please make sure to deep dive into all aspects of becoming an e-mail deliverability hero:

You might also want to go one step back to learn about the essentials of e-mail marketing. In case you need further support, please refer to our dedicated 'E-mail Deliverability Guidance' service. You will find more details in the fact sheet that is linked in the services section of this article.